ECT TH April 2019 PDF

 

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ECT Coaching TH

Q: The adoption of the code code of technical standards of practice, also known as the Philippine Electronics Code, consisting of  books 1, 2, 3 and 4 as part of of the rules and regulations governing the practice of Electronics Engineering and as a referral code to the National Building Code of the Philippines is Board of Electronics Engineering Resolution No. ______, Series of 2014 A: 12 *

Q: The Philippine Electronics Electronics Code Book 2 is about ________. A: Fire Detection Detection and Alarm System *

Q: Under ________ of R. A. No. 9292, the Professional Regulatory Board of Electronics Engineering is vested with the

Q: The National Building Code of the Philippines is Presidential Decree No. _. A: 1096 *

authority to adopt and administer a Code of Ethics and a Code of Technical Standards of Practice of Professional Electronics Engineers, Electronics Engineers and Electronics Technicians. A: Section 7 (1) * Q: Pursuant to ______ of R. R. A. No. 9292, the Board of Electronics Engineering is vested v ested A: with the authority to promulgate rules and regulations on the scope of practice of Professional Electronics Engineers, Electronics Engineers and Electronics Technicians. A. Section 7 (m) * Q: ________ of R. A. No. 9292 states that that the Board of Electronics Engineering shall formulate, prescribe and adopt such rules and regulations for electronics installations installations in industrial plants, commercial establishments and other buildings or structures covered by the National Building Code of the Philippines, in coordination with DPWH, other concern agencies, agen cies, representativess of industry and Accredited representative Professional Organization. A: Section 7 (p) * Q. PRC-BECE Resolution No. ______, Series of 2014, created an Ad Hoc Committee which formulate, prescribe and adopt the Electronics Code pursuant to the law. A: 6 * Q. The BECE Resolution No. 12, Series Series of 2014 which is the Adoption of the th e Code of Technical Standards of Practice or the Philippine Electronics Code was done in the City of Manila on _________. A: December 29, 2014 * Q: The effectivity effectivity of the Philippine Electronics Electronics Code (consisting of 4 books) is on _____. A: February 10, 2016 * Q: The BECE adopted the Philippine Electronics Code of 2014 during the meeting of the Ad Hoc Committee on _______. A: December 12, 2014 * Q: What states that “The Board shall adopt a Code of Ethics and the Code of T echnical Standards of Practice for Electronics Engineers and Electronics Technicians which shall be promulgated by the Accredited Professional Organization? A: Article IV, Section Section 30 *

Q: The Philippine Electronics Electronics Code Book 3 is about ________. A: Cable Television System * Q: The Philippine Electronics Electronics Code Book 4 is about ________. A: Distributed Antenna System System *

Q: What is otherwise otherwise known as Revised Fire Fire Code of the Philippines of 2008? A: R. A. No. 9514 * Q: The Philippine E Electronics lectronics Code Book 3 Television System  System is which is for Cable Television composed of how many chapters? 12 *

Q: Directional or panel antenna is a type of antenna that emits radio wave in one or two direction and usually has a beam width of A: 60 –  60 –  65  65 degrees* Q: What type of antenna is generally used to  provide coverage in in an open parking, lifts and elevators? A: Directional antenna for mic microcell rocell * Q; What is the frequency range (in MHz) of  panel antenna for microcell? A.  806 806 –   –  960  960 B.  1710 1710 –   2300  –  2300 C.  2400 2400 –   –  2700  2700 D.  All choices are correct * Q: What is the m maximum aximum power for panel antenna for microcell? A: 100 W * Q: ________ is the probabili probability ty of a call in a circuit group being blocked or delayed for more than a specified interval, expressed as a vulgar fraction or decimal fraction. A: Grade o off Service *

Q: The impleme implementation ntation of R. A. No. 9292 known as the “Electronics Law of 2004” in the process and approval of building permits When soldering electronic circuits be sure to: for building and structures required under (Ans.)   H ea eatt wi wi res until we wett ttii ng action begi begi ns. (Ans.) Presidential Decree No. 1096, the National What is the purpose of flux? Building Code of the Philippines is covered R em emove ovess oxi de dess ffrr om surface surf acess and prev pr event entss in the Board of Electronics Engineering Memorandum Circular No. ______.  formation  forma tion of oxi oxid des duri uring ng so solde lderi ng. (Ans.) (Ans.)   A: 2009-23 * During soldering operations, "wetting" is: Q: What DILG m memorandum emorandum circul circular ar informing the local government about the implementation implementatio n of the Electronics Engineering Law of 2004? A: MC No. 2013-01 *

Th The e blendi ble nding ng of solder solde coppe er to form a new alloy. alloy. (Ans.) (Ans.)    r and copp Solder most commonly used for hand soldering in electronics is:

(Ans.)   60% tin ti n 40% lea lead. d. (Ans.) Q: The Philippine E Electronics lectronics Code Book 4 (Distribution Antenna System) is composed of how many chapters? A: 6 *

Which of the following is true about the soldering tip?

The soldering tip should be tinned during the i ni nitial tial heat heatii ng up of of the solde solder i ng iiron. ron. (Ans.) (Ans.)  

Q: The Philippine E Electronics lectronics Code Book 2 (Fire Detection and Alarm System or FDAS) Which is an acceptable method of solder removal from holes in a printed board? is composed of how many chapters?  Solderi ng ir on and a suctio  Solde suction n device ice.. (Ans.)  (Ans.)  A: 4 * Q: According to the Philippine Ele Electronics ctronics Code, low rise buildings have number of floors between _______. A: 1st to 5th *

The ideal method of removing insulation from wire is:

The thermal stripper. (Ans.) 

Number of

The condition of a(n): a lead-acid storage battery is determined with

Low Rise

1 –  5  5

H ydrom ydromet ete er . (Ans.)  (Ans.) 

Mid Rise

6 –  15  15

High Rise

16 16 –   –  35  35

Super High Rise

36 36 –   –  70  70

Building type

71  - 100

Skyscraper

If a shunt motor, running with a load, has its shunt field opened, how would this affect the speed of the motor?

 Spee  Spe ed up up.. (Ans.)  (Ans.)  What is the purpose of using a small amount of solder on the tip of a soldering so ldering iron just prior to making a connection?

Q: What is the frequency (in MHz) of the omnidirectional antenna used in distribution  Ai ds in we wetti tti ng th the e wir es. (Ans.)  (Ans.)  antenna system? A: 806 –  806 –  960  960 and 1710 –  1710 –  2700  2700 * What occurs if the load is removed from an operating series DC motor? Q: What is the im impedance pedance (in ohms) of the wi ll accelerat accelerate e unt untii l iitt fli es apart. apart. (Ans.)  (Ans.)  omni-directional antenna used in distribution I t wi antenna system?  system?  Why do we tin component leads? A: 50 *

D ec ecrr eases eases heat heatii ng ti time me and aids iin n

Q: The Electronics Code Book 1 is Electronics aboutPhilippine ________. A: Telecommunic Telecommunications ations Facilities Facilities Distribution System *

Q: What is the ope operating rating temperature of the omni-directional antenna used in distribution antenna system? A: - 40C to + 60 C * 1

(Ans.)   connection. (Ans.) What does the acronym ESD stand for?

E lec lectrost trostat atii c D i schar schar ge (Ans.)  (Ans.) 

 

Excel Review Center Current amounts between ______ and _____ can be lethal.

ECT Coaching TH Current in a parallel circuit is:

100mA 100m A , 200mA (Ans.) (Ans.)  

inversely proportional to the circuits resistance. (Ans.)  (Ans.) 

What is the number one concern in regards to electrical electric al ssafety? afety?

With three 2.5k resistors and one 3.4k resistor in parallel, the total resistance is:

(Ans.)    Shock  Sho ck (Ans.) Bohr's Atomic Model consists of what three components?

Pr oto otons, ns, neutrons and e elect lectrr ons (Ans.)  (Ans.) 

The following is an example of a series parallel circuit. circuit.

(Ans.)   669.29 Ohms (Ans.) With one series 8 Ohm resistor connected to two in-parallel resistors, 20 and 30 ohms respectively, what is the total resistance (R t)?

 20 Ohms Ohms (Ans.) (Ans.)   Electrons are arranged in __ around a nucleus. nu cleus.

 Shells  She lls (Ans.) (Ans.)   What are three types of materials materials used in electronics?

C onductors, onductors, semi semi -conductors -conductors and insulat insu lators ors (Ans.)   (Ans.) Coulomb's Law describes the forces of attraction or repulsion between electrical electrical charges, which are _____ to the product of the charges _______to the distance between them.

directly proportional, inversely proportional (Ans.)   (Ans.) The magnetic field that surrounds a magnet can best be described as invisible lines of force, and are commonly referred to as:

line li ness o off flux. f lux. (Ans.)  (Ans.) 

Given a battery rated at 350 ampere-hours how many hours will the battery be able to provide 7 amperes? (Ans.)    50 (Ans.) A path between two or more points along which an electrical current can be carried is called a:

circuit. (Ans.) (Ans.)    NOT an effect effect of reflective radio fre frequency quency (RF) power?

F r eque quency ncy shift shi ft (Ans.)  (Ans.)  If the frequency of the source is 1 kHz, what is the value of the capacitive capacitive reactance (XC) of the circuit if the capacitor value is changed to 0.01 µF?

 A (Ans.) (Ans.)   The following resource is associated ass ociated with the next question.

 X C   = 15.9 k (Ans.)  (Ans.)  C  = An analog multimeter (AMM) checks for:

voltage, volt age, cur currr ent and resista resis tance. nce. (Ans.)  (Ans.) 

The frequency of the second harmonic of 60 Hz is:

An oscilloscope with two vertical inputs, is commonly referred to as a ____ oscillosco oscilloscope. pe.

120 Hz (Ans.) (Ans.)  

dual-trace (Ans.)  (Ans.) 

What is the approximate peak-to-peak voltage of a 2 VRMS sine wave?

Voltage or potential difference is the measure of potential energy between two points in a circuit and is commonly referred to as:

The formula for electric electrical al current is:

voltage drop. (Ans.) (Ans.)  

V olta oltage ge / R esis esista tance. nce. (Ans.)  (Ans.) 

What is impedance?

Electric current is the flow of which of the following?

T he resi r esistance stance of a com compone ponent nt at a gi ven  freque  freq uenc ncyy (Ans.)  (Ans.)  A resistor has three color bands of red, r ed, brown and brown. What is the ohmic value of this resistor?

In the circuit shown, the output at B is:

 5.6 V  p-p (Ans.)  (Ans.) 

E lectrons lectrons (Ans.)  (Ans.)  Which of the following is a unit of electric electrical al resistance?

Ohm (Ans.)  (Ans.)  

 210 Ohms Ohms (Ans.) (Ans.)   What components value is measured in mH?

I nd nduct uctor or (Ans.)  (Ans.)  Ohm's Law characterizes the relationship  between:

In a simple DC circuit with a constant voltage, where the resistance increases current will:

decrease decr ease (Ans.) (Ans.)   What type of circuit is shown in the diagram?

 po  power, resista resistanc nce e, ccurr urre ent and vo volt lta age. (Ans.)  (Ans.)  Ohm’s Law states t hat resistance is calculated  by voltage divided by current. Using Ohms law, how do you determine d etermine power?

C (Ans.)  This figure is a s chematic representati representation on of a/an:

Voltage times current (Ans.)  (Ans.)  Using a scientific calculator, a 3300 ohm resistor can be entered with scientific s cientific notation as:

 3.3 (Ans.) (Ans.) 10^3.  10^3. (Ans.) (Ans.)   Total resistance in a series circuit equals:

the sum of all the resi resisto storr values values withi wi thin n the circuit. (Ans.)  (Ans.)  If a series has three resistors valued 10k Ohms,circuit 15k Ohms and 20k 20 k Ohms, with at a voltage source of 15V, the total current will  be_____.

 333.33u  333 .33uA A (Ans.) (Ans.)  

 Series-Para  Series -Paralle llell (Ans.) (Ans.)   Zener diodes are most commonly used in:

 po  power su sup pply circuits. (Ans.)  (Ans.)  Compared to bipolar transistors, field effect transistors are NOT normally characterized by:

low input i nput iim mped pedance ance (Ans.)  (Ans.)  Compared to an effective voltage of 120 V AC, the average heat heat energy out of a resistor is  _____ for a voltage of 120 VDC.

the same same (Ans.)  (Ans.)  2

(Ans.)   voltage followe foll ower (Ans.) The relay contacts shown are:

 Si  Single ngle –  pole,  pole, single –   throw thr ow (Ans.)  (Ans.)   The basic properties associated with alternating voltage and current are:

 

Excel Review Center  frequenc  freque ncy, y, peri od, wave vele length ngth and amplitud litude e. (Ans.)   (Ans.)

ECT Coaching TH The following resource is associated ass ociated with the next question.

Given the series capacitive circuit below, what is the total capacitance?

0.008uF 0.00 8uF (Ans.) (Ans.)   If the output filter capacitor in a power supply actually had a value twice its stated s tated value, which of the following symptoms would be found?

The r i pp pple le voltage voltage would would be half of wha whatt is is expected expecte d and a small small i ncr ncrea ease se in i n the output voltage voltag e would be de detected tected.. (Ans.)  (Ans.)  Each type of coaxial cable is designed with_____________, which is dependent on materialss and dimensions used. material

The relay contacts shown are:

(Ans.)    Si  Single ngle –  pole,  pole, si single ngle –  throw  thr ow (Ans.) What is the calculated effective voltage for the wave form below?  5.48V  5.48 V (Ans.) 

Calculate the capacitive reactance reactance for 44 440 0 Hz and 9µF.

(Ans.)   40.21 Ohms (Ans.)

(Ans.)   characterr i sti characte sticc i mpeda pedance nce (Ans.) A coaxial cable's velocity of propagation factor depends on what two factors?

In a resistive-capacitive circuit the vector line relationship shows two lines perpendicular to each other. What is the phase relationship?

(Ans.)   D i electri electri c consta constant nt and p pe er mea eabil bilii ty (Ans.)

90 degree degr ee (Ans.)  (Ans.) 

In a series resistive and reactive r eactive circuit what formula is used to find total impedance?

 Z = sqrt( sqrt( R 2 + X  2 ) (Ans.)  (Ans.) 

What is the frequency of the sine wave below?

 250H  250 H z (Ans.)  (Ans.) 

In a capacitive circuit, what is the voltage and current relationship?

V oltage oltage lags (Ans.) (Ans.)  

0.2 (Ans.)  (Ans.) 

When the frequency of an applied voltage is increased the capacitive reactance of a circuit will:

Time is the:

decrease. (Ans.)  (Ans.) 

Express 1/5 as a decimal number.

dur duration ation betwe between en two well well-defi -defined ned events events (Ans.)  (Ans.)  The positively charged particle associated with the structure of an atom is called a/an:

In the illustration below, what component of the coaxial cable is letter “B”? “B” ?

Dielectric (Ans.)  (Ans.) 

What is the difference between calculating impedance for a series AC circuit and a  parallel AC circuit? circuit?

 A seri seri es impe impedanc nce e calcu calcula latio tion n is de deri ved ved  fr  fro om res resista istance nce and rea react cta ance, nce, while paralle rallel i mpe peda dance nce is i s calculate calculated with r esistive esisti ve and

(Ans.)    prot  proto on (Ans.)

rvoltage ea eactive ctive (Ans.)  curr ent divide ded d iinto nto the sour source ce   divi (Ans.)

If a gas in a fixed volume v olume container is heated, the resultant pressure on the gas:

(Ans.)   increases (Ans.) It takes 30 minutes to complete a reaction at 150 k. Which of the following is an estimate of the time required to complete the same reaction at 300k?

L ess than than 15 minutes (Ans.)  (Ans.) 

In an inductor/coil inductance varies as the  _______ of the number of turns.

 Squa  Squ are (Ans.) (Ans.)  

Silicon diodes have an approxi mate voltage drop of:

0.7V (Ans.) (Ans.)  

To properly bias the NPN transistor below, What is the total inductance of the th e circuit below? which voltages are correct? 4.24H (Ans.) 

E = -1; -1; B = +1; C = +10 (Ans.)  (Ans.) 

Vaporization refers to the change in state of matter from:

liqu li quii d tto o gas (Ans.)  (Ans.)  Energy is the capability or abi lity to:

do work work (Ans.)  (Ans.)  In regards to AWG standards, which gauge of wire has a bigger b igger cross-sectional area?

What will be the momentum of a 100 gm ball traveling with a velocity 10 cm/s?

1000 g m.cm/ .cm/ss (Ans.)  (Ans.)  A basic unit of r esistance is:

Ohm (Ans.) (Ans.)   A measure of how much a force acting on an object causes that object to rotate is called:

torque (Ans.)  (Ans.)  What are the characteristics of a coaxial cable?

I t has a cente centerr conducto conductorr cover ed wi wi th an i nsulato nsulatorr , then br br aided or soli solid do oute uterr conducto cond uctorr and then then iinsulation. nsulation. (Ans.)  (Ans.)  The following resource is associated with the next question.

The type of spring used in this solenoid s olenoid is:

compression (Ans.)  (Ans.) 

16 AWG (Ans.)  (Ans.)  Two basic uses for transformers are:

 sig  signa nall matching tching a and nd power su supp pplies lies.. (Ans.) (Ans.)   What is meant by "transformer action"?

Using ohm’s law for the circuit below, calculate the total power.

166.6 mW (Ans.)  (Ans.) 

The transfer of ene energ rg y from fr om one cir cuit to another anot her ci cirr cui cuitt by by elect electrr omagnetic omagnetic induct i nductii on (Ans.)  (Ans.)  What are the three basic parts of a transformer?

Pr i mary wi wi nd ndii ng, se seco conda ndarr y wi wi nd ndii ng and core (Ans.) (Ans.)   In the circuit below, what is the voltage output at letter “X”, when input voltage is 25V?  25V?  

In the circuit below, what is the calculated  power for R 3.

43.2W (Ans.)  (Ans.) 

(Ans.)   10V (Ans.)

The time required to charge a capacitor to 63  percent is known as:

(Ans.)   a time time constant. (Ans.) 3

In the circuit below, what is the current across R 2?

(Ans.)    2A (Ans.)

 

Excel Review Center

What is the voltage at terminal ‘A’ for the Wheatstone bridge below?

ECT Coaching TH A thyristor is a semiconductor with _____ layers that form ____ PN junctions.

What is the radix of the hexadecimal number system?

4, 3 (Ans.)  (Ans.) 

16 (Ans.)  (Ans.) 

Calculate total impedance for the circuit  below. 979.93 979. 93 ohms ohms (Ans.) 

What is the hexadecimal equivalent of the decimal number 622?

(Ans.)    26E (Ans.) What is the decimal sum of 10010 and 11001?

(Ans.)   1.86V (Ans.)

43 (Ans.)  (Ans.)  What is the digital gate equivalent for the circuit below?

NOR (Ans.) (Ans.)   Calculate the voltage drop across C 1. 4.7V (Ans.)  

What does LEC stand for?

L oc ocal al exchange exchange ccarr arrii er (Ans.)  (Ans.)  Circuit switch networks maintain only _____  path(s) for the duration of of the call.

One (Ans.)  (Ans.)   What formula is used to properly calculate ‘Vout’ for the voltage vo ltage divider below? below?  

V out   = (R 2 /R  /R 2+R 1  )) (Ans.)  (Ans.) V in (Ans.)   out  = in (Ans.)

If a signal decreases by 3 dB, how ho w much  power is lost?

 50  50% % (Ans.)  (Ans.)  -3dBm is equal to how many milliwatts? 0.5mW (Ans.)  What is Iz for the circuit below?

 5A (Ans.)  (Ans.) 

What does the acronym EAROM stand for?

E lect lectrr i cally A lte lterr ab able le R ead Only Memor Memor y (Ans.)  (Ans.)  What are three processor functions of a CPU?

 Ar ithme ithmetic logi logi c, interfac interfacing ing and and cont control rol (Ans.)  (Ans.)  If an oscilloscope TIME/DIV is set at 0.2 microseconds, and the width of the pulse measured is at 8 divisions on the scope graticule, what is the pulse width?

1.6 µs (Ans.)  (Ans.) 

When calculating power levels, which formula is correct? In the circuit below, what is the value of R 2? 75.75 75.7 5 ohms ohms (Ans.) 

dB = 10(Ans.) 10(Ans.)lo logg ( P  /P2)  1/P2) (Ans.)  (Ans.)  The formula to calculate dBm from mW is:

The split capacitors in a Colpitts oscillator  provide:

Lead and tin solder at a respective percentage of 63/37 melts at ______:

When keeping keeping fr eque quency ncy e err ror or dri dr i ft at a minimum is important (Ans.)  (Ans.)  What is the resonant frequency for the circuit  below? 75 kHz kH z (Ans.) 

Zener diodes are designed to operate in the  _____ bias region.

 361ººF . (Ans.)   361 (Ans.)  What four methods are used in coupling amplifier stages?

D i r ec ect, t, R C, i mpe peda dance nce and and tr tr ansfo ansforr mer coupling (Ans.) (Ans.)   What formula is used to calculate output voltage of a Difference Diff erence operational amplifier?

(Ans.)   V oout   /  /R R in )( V  2 - V 1  )) (Ans.) ut  = (R f  Due to the configuration of the filtering components, the ability of a_____ type filter to remove ripple voltage is superior to that of either the _______ or ________ filter.

reverse (Ans.)  (Ans.)  When compared to a JFET, the base of a  bipolar transistor is is similar to what eelement lement of the JFET?

Pi , capa capaciti citive ve,, i nductive nductive (Ans.) (Ans.)  

Gate (Ans.) (Ans.)  

Why is a differentiator used at the input of a flip-flop?

A MOSFET is comprised of what four elements?

To prod pr oduce uce a sha sharr p spik spike e (Ans.)  (Ans.) 

G ate, ate, source, sour ce, d drr ain and substr substr at ate e(Ans.)  (Ans.) 

What is one way to minimize parasitic oscillations?

How many PN junctions does a Unijunction transistor have?

Pl Place ace a sw swam amping ping r esi sistor stor across the transformer (Ans.)  (Ans.) 

One (Ans.) (Ans.)  

What type of diagram shows electrical connections and functions of a specific circuit arrangement?

 Schem  Sche matic (Ans.)  (Ans.)  Opening and closing vinyl envelopes used to carry work instructions, with 10 -20% relative humidity, electro-static voltages can reach as high as:

In a class ‘C’ collector: collector:   Which bipolar transistor configuration has a current gain of less than 1?

Why is flux used when soldering?

T o prevent the f orm or mation of me metal tal oxide oxi dess at (Ans.)   extr eme extrem e temperatur temperatures es (Ans.)

Why are crystal oscillators preferred over other types of oscillators?

H i gh i nput imp impe edance dance (Ans.)  (Ans.) 

 50 (Ans.)  (Ans.) 

(Ans.)   10 log 10 (P  ( P /1m /1mW) W) (Ans.)

r egener egener ati ati ve ffee eedb dback. ack. (Ans.) (Ans.)  

What is a primary advantage of a FET when compared to the bipolar transistor?

The coaxial cable leading to a cable TV is a 75 ohm transmission line. If you use 10Base2 coax cable for networking, that is a _____ ohm transmission line.

collectorr cur collecto currr ent flow flowss ffor or less than one half cycle of the input signal. (Ans.)  (Ans.) 

(Ans.)   C ommon ommon base (Ans.) 4

7,000V (Ans.)  (Ans.)   What is the modulus of a five-stage binary counter?

 

Excel Review Center (Ans.)    32 (Ans.) What is the preferred method for removing solder from a component attached to a circuit card assembly (CCA)?

 Moto  Mot ori ze zed d vacuum cuum extract xtraction ion (Ans.)  (Ans.)  To overcome noise, distortion and cost of maintenance in frequency division multiple systems, ________ systems were developed.

time-divi time -divisi sion on multiple multiplexx (Ans.)  (Ans.)  What are the three funda mental types of wireless access technologies?

(Ans.)   F DMA , CDMA and and TDMA (Ans.) In the kinescope, the ________ intensity of an electron beam from an electron gun is modulated in accordance with the ________ variations of signals received by a control electrode, or modulator.

cur currr ent ent,, amplitude amplitude (Ans.)  (Ans.)  An electromagnetic wave is composed of an electromagnetic electromagne tic and electric field, which are at  ______ from one another.

(Ans.)   90 degree degr ees (Ans.) A vertically polarized antenna has a magnetic field that is at a _____ angle to the axis of the antenna.

90 degree degr ee (Ans.)  (Ans.) 

ECT Coaching TH In a voltage regulator incorporating foldback current limiting, output current decreases with:

C. Requires an output tank ccircuit ircuit to produce an undistorted output.

E xcessi xcessive ve i nput nput/o /outp utput ut vvolta oltagg e dif differ ferent entii al. (Ans.)  (Ans.) 

D . A ll of of tthe hese. se. (Ans.) (Ans.)   The element silicon is:

When it has been determined that a zener reference diode in a regulated power supply has avalanche breakdown, the best thing to do is: A. Replace the diode with with one with higher ratings. B. Replace the dio diode de with one having the same specifications. C. Remove the diode from the circuit and retest it.

70 MH z (Ans.) (Ans.)   In a common anode, seven-segment LED display, an individual LED will light if a negative voltage is applied to what element?

Cathode (Ans.)  (Ans.)  What is the purpose of a bypass b ypass capacitor?

I t re r emov ove es alter alter na nating ting curr ent by providi providing ng a low im i mpedance pedance p path ath to gr ound. (Ans.) (Ans.)   What is the purpose of a coupling capacitor? capacitor?

Itb bocks ocks dir ec ectt curr ent and passes passes alternating alternating current. (Ans.) (Ans.)   An advantage of high frequency operation of a DC-DC converter is:

falls below the trigger point with anode and cathode voltage applied?

 se  sem mico icond nduc ucto torr (Ans.)  (Ans.)  In an atom:

the elect electrr ons orbi orbitt the nucleus (Ans.)  (Ans.)  An atom that loses an electron becomes:

ap positi ositive ve i on (Ans.) (Ans.)  

If a zener breakdown occurs at 24 volts, in which mode does it operate?

An electric current passing through a wire will  produce around the conductor:

(Ans.)    Avala  Ava lanch nche e (Ans.)

a magnetic magnetic fi f i eld (Ans.)  (Ans.) 

After the emergency generator was tested online, the GMDSS VHF transceive transceiverr failed. The defective power supply fuse was replaced but failed again. again. Which of the following corrective actions could safely get the power supply working again?

R ep eplace lace the shorted SC R i n the crowb crowbar. ar. (Ans.)  (Ans.) 

These magnetic poles repel:

like (Ans.) (Ans.)   This material is better for making a permanent magnet:

 ste  steel (Ans.)  (Ans.)  The better conductor of electricity electricity is:

copper copp er (Ans.) (Ans.)   Edison type storage cell battery charge condition can be determined by:

The term describing opposition to electron flow in a metallic circuit is:

resistance (Ans.)  (Ans.)  Lead-acid type storage cell battery charge condition can best be determined by:  Mea  Measuring suring tthe he sp spe ecific gravity gravity of tthe he electrr olyte. elect olyte. (Ans.)  (Ans.)  Internal resistance of a battery is: A. A fixed resistor plac placed ed physically in inside side  battery to limit limit current flow. B. A fixed resistor place placed d physically inside  battery to provide a trickle flow of electrons during unused periods. C. Resistance me measured asured when plates short circuit internally. D . N one of the these. se. (Ans.) 

The substance which will most readily r eadily allow an electric current to flow is:

a conductor (Ans.)  (Ans.)  The plastic coating formed around wire is:

an insulat i nsulato or (Ans.)  (Ans.)  The following is a source of electrical energy:

(Ans.)   lead acid batter batter y (Ans.) An important difference between a common torch battery and a lead acid battery is that only the lead acid battery:

can be r e-char e-char g ed (Ans.) (Ans.)   The most common acid used in lead-acid  batteries is: is:

 Sulphuric  Sulp huric Acid (Ans.)  (Ans.) 

 A sma small filt fi lte er cca apacitor citor m ma ay be used used. (Ans.)  (Ans.)  What happens if the gate voltage on an SCR

An element which falls somewhere between b etween  being an insulator insulator and a conductor is calle called d a:

D . N one of the these. se. (Ans.)  (Ans.) 

 Measuring  Mea suring vvo olta ltage with cell cell und unde er loa load.(Ans.)  (Ans.)  The 4-meter frequency band is also known as the _____ band.

a semiconductor (Ans.)  (Ans.)  

As temperature increases, the resistance of a metallic conductor:

increases (Ans.)  (Ans.)  The approximate voltage of a fully charged lead-acid battery cell is:

 2.1 (Ans.)  (Ans.) 

In an n-type semiconductor, the current carriers are:

electrons (Ans.)  (Ans.) 

The SCR SC R stays stays on. on. (Ans.)  (Ans.) 

The common type dry cell battery contains:

A power supply crowbar circuit may consist of a:

Energy stored in a lead-acid battery is:

In a p-type semiconductor, the current carriers are:

Chemical (Ans.) (Ans.)  

holes (Ans.) (Ans.)  

A fully charged lead-acid battery rated at 500 amp-hours could power a: A. 10 amp receiver for 50 hours. B. 50 amp load for 10 hours. C. 5 amp lload oad for 100 h hours. ours.

An electrical insulator:

Carbon and zinc. (Ans.)  (Ans.)   Zene  Ze nerr d diod iode e and SCR . (Ans.) (Ans.)   What would be the effect of an open filter f ilter capacitor in a DC power supply under load?

The D C outp output ut voltage voltage would would drop. (Ans.)  (Ans.)  Most switching power supplies do not use a line isolation isolation transformer. This implies the following:

There is no line isolation. isolation. Usi ng a groun gr ounde ded d  scope in tthis  scop his syst syste em will destroy stroy th the e supp supply ly.. (Ans.) (Ans.)  

do doe es not let e elect lectrr i ci city ty flow through i t (Ans.) (Ans.)   Four good electrica electricall insulators are:

 glass,  glas s, air , plast lastic, ic, po porcela rcelain in (Ans.)  (Ans.) 

(Ans.)   D . A ll these. these. (Ans.) Three good electrical conductors are: Crossover distortion in a push-pull p ush-pull amplifier occurs when DC base voltage is zero and input signal voltage has not exceeded V be. (Ans.)  

 gold,, silver,  gold silver, a alum luminum inum (Ans.)  (Ans.)  The name for the flow of electrons in an electric circuit is:

(Ans.)   current (Ans.) In a switching power supply, the output

A single stage transistor RF a mplifier operated

voltage controlled inck thetofollowing manner: F eeding eedingisthe out output put ba back ei ei the therr a DC/DC DC /DC

class B: A. Operates in the linear linear range for 180 degrees of the input signal cycle and is cutoff for the remaining 180 degrees. B. Is more efficient than a class A amplifier.

chopperr or a Pulse choppe Pu lse Width Wi dth Modulate Modulated d inve i nverr ter ter . (Ans.)  (Ans.) 

5

The of impedance is the: (Ans.)    ohmunit (Ans.) One kilohm is:

1000 ohm (Ans.) (Ans.)  

 

Excel Review Center One kilovolt is equal to:

1000 volt volt (Ans.) (Ans.)   One quarter of one ampere may be written as:

(Ans.)    250 milliam illiamp pere (Ans.)

ECT Coaching TH R = E / I [ r esistance eq equals uals vo voltage ltage d dii vided by current] (Ans.) (Ans.)   A resistor with 10 volt applied across it and  passing a current of 1 mA has a value of:

(Ans.)   10 ki lohm (Ans.)

The voltage 'two volt' is also:

If a 3 volt battery causes 300 mA to flow in a circuit, the circuit resistance is:

volt (Ans.)  (Ans.)  Impedance is a combination of:

r esistance with r ea eacta ctance nce (Ans.)  (Ans.) 

A current of 0.5 ampere flows through a resistor when 12 volt is applied. The value of the resistor is:

 24 ohm hmss (Ans.)  (Ans.) 

Five 10 ohm resistors connected in series give a total resistance of:

 50 ohms hms (Ans.)  (Ans.)  Resistors of 10, 270, 3900, 3900 , and 100 ohm are

The resistor which gives the greatest opposition to current flow is:

0.5 megohm (Ans.)  (Ans.) 

connected in series. The total resistance is:

(Ans.)   4280 ohm (Ans.)

This combination of series resistors could replace a single 120 ohm resistor:

One mA is:

one thousandth of one ampere ampere (Ans.)  (Ans.) 

 gr eater ttha han n th the e res resista istance nce of any one resistor (Ans.)   (Ans.)

(Ans.)   10 ohm (Ans.)

 2000  200 0 mV (Ans.)  (Ans.)   The unit for pot ential difference between two  points in a circuit circuit is the:

 5 ohm (Ans.)  (Ans.)  The total resistance of several resistors connected in series is:

The watt is the unit of:

 po  power (Ans.)  (Ans.) 

A 6 ohm resistor is connected in parallel with a 30 ohm resistor. The total resistance of the combination is:

 fi  five ve 24 ohm (Ans.)  (Ans.) 

The ohm is the unit of:

electrical resistance (Ans.)  (Ans.)  The unit of resistance is the:

ohm (Ans.)  (Ans.) 

If a 12 volt battery supplies 0.15 ampere to a circuit, the circuit's resistance is:

The voltage across a resistor carrying current can be

(Ans.)   80 ohm (Ans.)

E = I x R [volta [voltage ge e equa quals ls curr ent ttii mes resistance] (Ans.)  (Ans.) 

If a 4800 ohm oh m resistor is connected to a 12 volt  battery, the current current flow is:

If a 2.2 megohm and a 100 kilohm resistor are connected in series, the total resistance is:

 2.3 megohm gohm (Ans.) (Ans.)   If ten resistors of equal value R are wired in  parallel, the total resistanc resistancee is:

(Ans.)   R/10 (Ans.)

 2.5 mA (Ans.)  (Ans.)  A 10 mA current is measured in a 500 5 00 ohm resistor. The voltage across the resistor will be:

 5 volt volt (Ans.) (Ans.)  

The total resistance in a parallel circuit:

i s alway alwayss less than the smallest r esi esistance stance (Ans.)  (Ans.) 

The value of a resistor to drop 100 1 00 volt with a

The total resistance of four 68 ohm resistors r esistors wired in parallel is:

17 ohm (Ans.) (Ans.)   Resistors of 68 ohm, 47 kilohm, 560 ohm and 10 ohm are connected in parallel. The total resistance is:

I = E/R is a mathematical equation describing:

Two resistors are connected in parallel p arallel and are connected across a 40 volt battery. If each resistor is 1000 ohms, the total battery current is :

Ohm'' s Law Ohm L aw (Ans.)  (Ans.) 

80 milli mil liam ampe perr e (Ans.) (Ans.)  

The following resistor combination can most nearly replace a single 150 ohm resistor:

The voltage to cause a current of 4.4 ampere in a 50 ohm resistance is:

The total current in a parallel circuit is equal to the:

(Ans.)   three 47 47 ohm r esi sisto stors rs i n serie seri es (Ans.)

current of 0.8 milliampe milliampere re is:

125 ki lohm (Ans.)  (Ans.) 

(Ans.)    220 volt (Ans.) A current of 2 ampere flows through a 16 ohm resistance. The applied voltage is:

 32 vo volt lt (Ans.) (Ans.)  

 sum of the the curr curr ents nts throu through gh all th the e parall ralle el (Ans.)   branches (Ans.) One way to operate a 3 volt bulb b ulb from a 9 volt supply is to connect it in:

 se  seri ri es with a res resisto istorr (Ans.) (Ans.)   A current of 5 ampere in a 50 ohm resistance  produces a potential potential difference of:

 250 volt (Ans.)  (Ans.)  This voltage is needed to cause a current of 200 mA to flow in a lamp of 25 ohm resistance: (Ans.)    5 volt volt (Ans.) A current of 0.5 ampere flows through a resistance when 6 volt is applied. To change the current to 0.25 ampere the voltage must be:

r educe educed d to 3 volt (Ans.) (Ans.)   The current flowing through a resistor can be calculated calcula ted by using th thee formula:

I = E / R [cur r en entt equa equals ls voltage voltage di di vide vided d by by resistance] (Ans.)  (Ans.)  When an 8 ohm resistor is connected conn ected across a 12 volt supply the current flow is:

12 / 8 amps (Ans.)  (Ans.)  A circuit has a total resistance of 100 ohm and 50 volt is applied across it. The current flow will be:

(Ans.)    500 mA (Ans.) The following formula gives the resistance of a circuit:

You can operate this number of identical lamps, each drawing a current of 250 mA, from a 5A supply:

(Ans.)    20 (Ans.)

less than 10 ohm (Ans.)  (Ans.) 

Two 120 ohm resistors are arranged in parallel to replace a faulty resistor. r esistor. The faulty resistor had an original value of:

60 ohm (Ans.) (Ans.)   Two resistors are in parallel. Resistor A carries twice the current of resistor B which means that:

 A has has ha half lf th the e res resii st sta anc nce e of B (Ans.)  (Ans.)  The smallest resistance that can be made with five 1 k ohm resistors is:

Six identical 2-volt bulbs are connected in series. The supply voltage to cause the bulbs to light normally is:

 200 ohm them i n parallel (Ans.)    by arr anging the (Ans.)

12 V (Ans.) (Ans.)  

The following combination of 28 ohm resistors has a total resistance of 42 ohm:

This many 12 volt bulbs can be b e arranged in series to form a string of lights to operate from a 240 volt power supply:

a com combination of two r esistors i n par par allel, allel, then place placed d in ser serii es wi wi th anothe anotherr r esistor (Ans.)  (Ans.) 

 240 / 12 (Ans.)  (Ans.)  Three 10,000 ohm resistors are connected in series across a 90 volt supply. The voltage drop across one of the r esistors is:

Two 100 ohm resistors connected in parallel are wired in series with a 10 ohm oh m resistor. The total resistance of the combination is:

60 ohms (Ans.)  (Ans.) 

 30 volt volt (Ans.)  (Ans.)  Two resistors are connected in parallel. p arallel. R1 is 75 ohm and R2 is 50 5 0 ohm. The total resistance of this parallel circuit is:

(Ans.)    30 ohm (Ans.)

A 5 ohm and a 10 ohm resistor are wired in series and connected to a 15 volt power supply. The current flowing from the power supply is:

1 amper amper e (Ans.)  (Ans.) 

A dryWhen cell has an openacircuit voltagethe of 1.5 volt. supplying large current voltage drops to 1.2 volt. This is due du e to the cell's:

i nte nterr nal nal r esi sista stance nce (Ans.)  (Ans.)  6

Three 12 ohm resistors are supply. wired parallel and connected to an 8 volt sup ply.inThe total current flow from the supply is:

 2 amperes (Ans.)  (Ans.) 

 

Excel Review Center Two 33 ohm resistors are connected in series with a power supply. If the current curr ent flowing is 100 mA, the voltage across one of the r esistors is:

(Ans.)    3.3 vo volt lt (Ans.)

ECT Coaching TH r eactance eactance (Ans.) (Ans.)  

(Ans.)   dielectric (Ans.)

Three 18 ohm resistors are connected in  parallel across across a 12 volt supply. The total  power dissipation of of the resistor load is:

Three 15 picofarad capaci capacitors tors are wired in  parallel. The value of the combin combination ation is:

45 picofarad picofar ad (Ans.)  (Ans.) 

 24 watt (Ans.)  (Ans.)  A simple transmitter requires a 50 ohm dummy load. You can fabricate this from:

 six 300 300 ohm res resisto istors rs in paralle rallel (Ans.)  (Ans.) 

The reactance of a capacitor increases as the: A resistor of 10 kilohm carries a current of 20 mA. The power dissipated in the resistor is:

4 watt (Ans.)  (Ans.)  Three 500 ohm resistors are wired in series. Short circuiting the centre resistor will change the value of the network from:

(Ans.)   1500 ohm to to 1000 ohm (Ans.)

 fr  fre eque uenc ncyy decrea crease sess (Ans.) (Ans.)   The reactance of an inductor increases as the:

 fr  fre eque uenc ncyy increase increasess (Ans.)  (Ans.)  A resistor in a circuit becomes very hot and starts to burn. This is because the resistor is dissipating too much:

Increasing the number of turns on an inductor will make its inductance:

 po  power (Ans.) (Ans.)  

increase (Ans.)  (Ans.) 

A current of 10 ampere rms at a frequency of 50 Hz flows through a 100 ohm resistor. The  power dissipated is: is:

The unit of inductance is the:

The DC input power of a transmitter operating at 12 volt and drawing 500 milliamp milliamp would be:

10,000 watt (Ans.) (Ans.)  

Two 20 H inductances are connected in series. The total inductance is:

(Ans.)   6 watt (Ans.)

The voltage applied to two resistors in series is doubled. The total power dissipated d issipated will:

(Ans.)   40 H (Ans.)

When two 500 ohm 1 watt resistors are connected in series, the maximum total power that can be dissipated by both resistors is:

i ncr ncre ease by four four time timess (Ans.)  (Ans.) 

Two 20 H inductances are connected in  parallel. The total inductance iis: s:

An 'alternating current' is so called because:

10 H (Ans.) (Ans.)  

A transmitter power amplifier requires 30 mA at 300 volt. The DC input power is:

9 watt (Ans.)  (Ans.) 

 2 watt (Ans.) (Ans.)   When two 1000 ohm 5 watt resistors are connected in parallel, they can dissipate a maximum total power of:

10 watt (Ans.) (Ans.)  

i t r ev eve er se sess di r ecti cti on pe periri odi odi cally cally (Ans.) (Ans.)   The time for one cycle of a 100 10 0 Hz signal is:

(Ans.)   0.01 second (Ans.) A 50 hertz current in a wire means that: a cycle is is comp complete leted d 50 titime mess i n each se  seco nd   cond

(Ans.)  (Ans.)  The current in a 100 kilohm resistor is 10 mA. The power dissipated is:

The current in an AC circuit completes a cycle

(Ans.)   10 watt (Ans.)

in 0.1 second. So the frequency is:

A current of 500 milliamp passes through a 1000 ohm resistance. The power dissipated is:

(Ans.)    250 watt (Ans.)

10 Hz H z (Ans.)  (Ans.) 

An impure signal is found to have 2 kHz and 4 kHz components. This 4 kHz signal is:

a har har monic of the 2 kH z sig signa nall (Ans.)  (Ans.)  A 20 ohm resistor carries a current of 0.25 0 .25 ampere. The power dissipated is:

1.25 watt (Ans.)  (Ans.) 

The correct name for the equivalent of 'one cycle per second' is one:

hertz (Ans.) (Ans.)   If 200 volt is applied app lied to a 2000 ohm resistor, the resistor will dissipate:

 20 watt (Ans.)  (Ans.)  The power delivered to an antenna is 500 watt. The effective antenna resistance is 20 ohm. The antenna current is:

(Ans.)    5 amp (Ans.)

One megahertz is equal to:

(Ans.)   1000 kH z (Ans.)

henry (Ans.)  (Ans.) 

A toroidal inductor is one in which the: windings are wound on a closed ring of

ma magg net netii c materi aterial al (Ans.) (Ans.)   A transformer with 100 turns on the th e primary winding and 10 turns on the secondary winding is connected to 230 volt AC mains. The voltage across the secondary is:

 23 volt volt (Ans.)  (Ans.)  An inductor and a capacitor are connected in series. At the resonant frequency the r esulting impedance is:

minimum (Ans.)  (Ans.)  An inductor and a capacitor are connected in  parallel. At the resonant frequency the resulting impedance is:

maximum (Ans.)  (Ans.)  An inductor and a capacitor form a resonant r esonant circuit. The capacitor value is increased by four times. The resonant frequency will:

One GHz is equal to:

1000 MH z (Ans.)  (Ans.) 

decrease to to half (Ans.)  (Ans.) 

The 'rms value' of a sine-wave signal is:

0.707 0.707 ti mes the pea peakk voltag voltag e (Ans.) (Ans.)  

An inductor and a capacitor form a resonant r esonant circuit. If the value of the inductor is decreased  by a factor of four, the resonant frequency

(Ans.)   watt (Ans.)

A sine-wave alternating current of 10 ampere  peak has an rms value of:

will:

The following two quantities should be be multiplied together to find power:

(Ans.)   7.07 7.07 amp (Ans.)

voltage volt age and curr ent (Ans.) (Ans.)  

The total capacitance of two or more capacitors in series is:

The unit for power is the:

The following two electrical units multiplied together give the unit "watt":

(Ans.)   volt and amper amper e (Ans.)

always lless always ess than that of the smallest cap capaci acitor tor (Ans.)   (Ans.)

The power dissipation of a resistor carrying a current of 10 mA with 10 volt across it is:

Filter capacitors in power supplies are sometimes connected in series to:

0.1 0.1 watt (Ans.)  (Ans.) 

withstand a grea gr eate terr volta voltagg e tha than n a si sing ngle le capacitor can withstand (Ans.) (Ans.)  

If two 10 ohm resistors are connected in series with a 10 volt battery, the battery load is:

 5 watt (Ans.)  (Ans.) 

A radio component is identified as a capacitor if its value is measured in:

(Ans.)   microfarads (Ans.) Each of 9 resistors in a circuit is dissipating 4 watt. If the circuit operates from a 12 volt supply, the total current flowing in the circuit is:  3 ampere (Ans.) Capacitors and inductors oppose an a lternating current. This is known as:

i ncr ncre ease by by a factor factor of two (Ans.)  (Ans.)  A "high Q" resonant circuit is one which:

(Ans.)   i s hi highly ghly select selectii ve (Ans.) You can safely remove an unconscious person from contact with a high voltage source by:

turni ng off the hig h voltage voltage a and nd the then n (Ans.)   r em emov ovii ng the person person (Ans.) For your safety, before checking a fault in a mains operated power supply unit, first:

turn tur n off the powe power and remove remove the pow power er plug (Ans.) (Ans.)   Wires carrying high voltages in a transmitter should be well insulated to avoid:

Two metal plates separated by air form a 0.001 F capacitor. Its value may be changed to

 short  sho rt circuits (Ans.)  (Ans.) 

0.002 F by:

A residual current device is recommended for  protection in a mains mains power circuit bec because ause it:

bri ngi ng the m met etal al plat plate es close cl oserr tog tog ether  ether   (Ans.)  (Ans.)  The material separating the plates of a capacitor is the: 7

r em emove ovess power power to the ci cirr cui cuitt when the phase phase and neutral neutral cur currr ents ents are ar e not equa equall (Ans.)  (Ans.) 

 

Excel Review Center An earth wire should be connected to the th e metal chassis of a mains-operated power supply to ensure that if a fault develops, the chassis:

does n not ot d deve evelop lop a hi higg h voltage with wi th rrespe espect ct (Ans.)   to earth earth (Ans.)

ECT Coaching TH A semiconductor is described as a "general  purpose audio NPN device". device". This is a:

bipolar bipo lar transistor (Ans.) (Ans.)  

100 (Ans.) (Ans.)   Two basic types of bipolar transistors are:

(Ans.)   NP N and PNP type typess (Ans.) The purpose of using three wires in the th e mains  power cord and plug on amateur amateur radio equipment is to:

 prev  preve ent th the e cha chassis from becom coming live in case of an inte i nterr nal short to the chassis chassis (Ans.)  (Ans.) 

A transistor can be destroyed in a circuit by:

excessive heat (Ans.)  (Ans.) 

at the emi tte tterr po potential tential (Ans.)  (Ans.) 

brown (Ans.)  (Ans.) 

Two basic types of field effect transistors are:

(Ans.)   blue (Ans.)

n-channel and p-channel (Ans.) (Ans.)   A semiconductor with leads labeled gate, drain and source, is best described as a:

(Ans.)    fie  fi eld-e ld-effec ffectt trans ransisto istorr (Ans.) The correct color coding for the earth wire in a flexible mains lead is:

 yello  yellow w and gr een (Ans.) (Ans.)  

An ohmmeter measures the:

value of any r esi esistance stance placed placed b bet etwe ween en iits ts terminals (Ans.) (Ans.)   A VSWR meter switched to the "reverse"  position provides an indication indication of:

r elati elati ve r eflected voltag voltag e (Ans.)  (Ans.)  The basic semiconductor amplifying device is a:

An attenuator network has 10 volt rms applied app lied to its input with 1 volt rms measured at its output. The attenuation of the network is:

(Ans.)    20 dB (Ans.) An attenuator network has 10 volt rms applied app lied to its input with 5 volt rms r ms measured at its output. The attenuation of the network is:

6 dB dB (Ans.)  (Ans.)  Two amplifiers with gains of 10 dB and 40 4 0 dB are connected in cascade. The gain of the combination is:

 50 dB (Ans.) (Ans.)  

An isolating transformer is used to:

ensur e that no voltage ensur voltage iiss developed developed be betwee tween n (Ans.)   either eith er output lead lead and gr ground ound (Ans.)

An attenuator network comprises two 100 ohm resistors in series with the input applied across  both resistors and the output taken from across one of them. The attenuation of the network is:

6 dB dB (Ans.)  (Ans.)  To bias a transistor to cut-off, the base must  be:

The correct color coding for the phase wire in a flexible mains lead is:

The correct color coding for the neutral wire in a flexible mains lead is:

A transmitter power amplifier has a gain of 20 dB. The ratio of the output power po wer to the input  power is:

An amplifier with a gain of 20 dB has a -10 dB attenuator connected in cascade. The gain of the combination is:

The correct instrument for measuring the supply current to an amplifier is a:

10 dB dB (Ans.)  (Ans.) 

ammeter amme ter (Ans.)  (Ans.) 

Each stage of a three-stage amplifier provides 5 dB gain. The total amplification is:

(Ans.)   voltage volt age reg regulato ulatorr s (Ans.)

The following meter could be used to measure the power supply current drawn by b y a small

15 dB dB (Ans.)  (Ans.) 

The voltage drop across a germanium signal diode when conducting is about:

hand-held transistorized receiver:

A mains operated DC power supply

When measuring the current drawn by a light  bulb from a DC supply, the meter will ac actt in circuit as:

The following unit in a DC power supply supp ly  performs a rectifying rectifying operation:

(Ans.)   a low value value rresis esistance tance (Ans.)

a full-wave ful l-wave diode bri dge (Ans.) (Ans.)  

collector, emitter, emitter , base (Ans.) (Ans.)  

When measuring the current drawn by a receiver from a power supply, the current meter should be placed:

The following unit in a DC power supply supp ly  performs a smoothing operation: operation:

A low-level signal is applied to a transistor circuit input and a higher-l evel signal is  present at the output. This effec effectt is known as:

i n seri es with bo both th rrece ecei ve verr po powe werr leads leads d. in i n seri es w wii th one of the r ecei ver ver po powe werr leads (Ans.)  (Ans.) 

transistor (Ans.) (Ans.)   Zener diodes are normally used as:

a DC ammeter (Ans.) (Ans.)  

0.3V (Ans.)  (Ans.)   A bipolar transistor has three terminals named:

emi emi tte tterr , base and coll collecto ectorr (Ans.)  (Ans.)  The three leads from a PNP transistor are named the:

amplification (Ans.) (Ans.)   The type of rectifier r ectifier diode in almost exclusive use in power supplies is:

(Ans.)    silico  sili con n (Ans.)

converts ene converts energ rg y from fr om the mai ns i nto D C for op ope er ati ati ng electr lectr onic eq equi uipm pmen entt (Ans.)  (Ans.) 

an electr electr olyti olyti c capaci capacito torr (Ans.)  (Ans.)  The following could power a solid -state 10 watt VHF transceiver:

a 12 volt car batter batter y (Ans.)  (Ans.)  An ammeter should not be connected directly across the terminals of a 12 volt car battery  because:

the r esulting esulting high hi gh curr ent wi wi ll prob probab ably ly destroy destr oy the am amme meter ter (Ans.)  (Ans.) 

A fullwave DC power supply operates from the New Zealand AC mains. The ripple frequency is

100 Hz (Ans.)  (Ans.)  

One important application for diodes is recovering information from transmitted trans mitted signals. This is referred to as:

A good ammeter should have:

a ver ver y low i nte nterr nal re r esi sistanc stance e (Ans.)  (Ans.) 

The capacitor value best suited for f iltering the output of a 12 volt 1 amp DC power supply is:

demodulation (Ans.)  (Ans.) 

A good voltmeter should have:

10,000 10,0 00 F (Ans.)  (Ans.) 

(Ans.)   a ver ver y hig h inte i nterr na nall r esi sista stance nce (Ans.) In a forward biased pn junction, the electrons:

 flow  flo w from n to p (Ans.)  (Ans.)  The following material is considered to be a semiconductor:

An rms -reading voltmeter is used to measure a 50 Hz sinewave of known p eak voltage 14 volt. The meter reading will be about:

capacitance (Ans.) (Ans.)  

a fuse fus e iin n the mains mains lead lead (Ans.)  (Ans.)  

10 volt (Ans.)  (Ans.) 

 silico  sili con n (Ans.)  (Ans.)  A varactor diode acts like a variable:

The following should always be included as a standard protection device in any power supply

The input to an amplifier is 1 volt rms and t he output 10 volt rms. This is an increase of:

 20 dB (Ans.)  (Ans.) 

A halfwave DC power supply operates from the New Zealand AC mains. The ripple frequency will be:

 50 H z (Ans.) (Ans.)  

A semiconductor is said to be doped when small quantities quantities of the following are added:

The input to an amplifier is 1 volt rms and output 100 volt rms. This is an increase of:

impurities (Ans.)  (Ans.) 

40 dB dB (Ans.)  (Ans.) 

The output voltage of a DC power supply s upply decreases when current is drawn from it  because:

The connections to a semiconductor diode are ar e

An amplifier has a gain of 40 dB. The ratio of

all power supplies suppli es have some i nternal nternal resistance (Ans.)  (Ans.) 

known as:

the rms output voltage to the rms input voltage is:

anode and cathode cathode (Ans.)  (Ans.) 

100 (Ans.)  (Ans.) 

Electrolytic capacitors capacitors are used in power supplies because

they can can be obtain obtained ed i n larg lar g er values than other types types (Ans.)  (Ans.) 

Bipolar transistors usually have:

 3 conne connect ctii ng le lea ads (Ans.)  (Ans.)  8

 

Excel Review Center The filter in the power supply circuit is used to:

 smooth th  smo the e rec rectified tified wave vefo form rm from the the rectifier (Ans.) (Ans.)  

ECT Coaching TH Ohms per volt (Ans.)  (Ans.) 

diagnostic equipment into calibration facilities?

What is the term used to refer to the losses lo sses which can be traced to the dielectric of a capacitor?

The regulator in the power supply circuit is used to:

Powerr losses (Ans.)  Powe (Ans.) 

keep the output voltage at a constant value (Ans.)   (Ans.)

What effect does an increase in capacitance have on a capacitor’s opposition to current flow?

The transformer in the power supply circuit is used to:

(Ans.)   Opposi Oppo sition tion to curr cur r ent flow de decr crea eases ses (Ans.)

transform transf orm the mains mains A C voltage voltage to a more more convenient conveni ent A C voltage voltage (Ans.) (Ans.)  

When a bridge is used to measure resistance, r esistance, what is the value of Rx if R1 equals 80 ohms, R2 equals 120 ohms and R3 equals 280 ohms?

The rectifier in the power supply circuit is used to:

420 ohms ohms (Ans.) (Ans.)  

tur turn n the A C voltage voltage fr from om the transforme transf ormerr i nto (Ans.)   a fluctuating fluctuating D C vo volta ltage ge (Ans.)

When an unknown capacitance is tested with a  bridge, what is the value of Cx if R1 eequals quals 70 ohms, R2 equals 150 ohms, and Cs equals 550 microfarads?

The regulator in the power supply circuit could consist of:

 ME ASUR AS UR E (Ans.)  (Ans.)   What are the three hazards that could create damage to electrical measuring instrument?

1. M echa chani nica call shock (Ans.)  (Ans.)  (Ans.)    2. E xpo xposure sure to magnet gnetic field field (Ans.)  3. E xce xcessive ssive current current flow flow (Ans.)  (Ans.)  The possibility of electrical shock can be reduce by ensuring all motors, generators, and other electronic equipments are at _______.

 gr oun und d potent tential ial (Ans.)  (Ans.)  What meters operate from their own power sources?

(Ans.)    256 microfarad icrofaradss (Ans.)

 Self-e  Sel f-excite xcited d (Ans.)  (Ans.)  What physical components of a galvanometer  provides the restoring forces forces for the coil?

Phosphor bronze ribbons (Ans.)  (Ans.) 

a three-terminal regulator chip (Ans.)  (Ans.)  A power supply is to power a solid-state transceiver. transceive r. A suitable over-voltage protection device is a:

cr crow owba barr across the re r eg ulator ulator out output put (Ans.)  (Ans.)  In a regulated power supply, the 'crowbar' is a:

last-ditch protection protection agai against nst failur fail ure e of of the r egulato egulatorr i n the supp supply ly (Ans.)  (Ans.) 

What is used for precise measurement of resistance?

In a galvanometer, what two methods are used to indicate the amount of coil rotation?

(Ans.)   Wheatstone Wheat stone b brr i dge (Ans.)

1. The pointer arrangement (Ans.)  (Ans.)  (Ans.)    2. The light lig ht and mir ror arr arr angem ngement (Ans.)

What is used for measuring an unknown capacitance?

C ap apacitance acitance bridge bri dge (Ans.) (Ans.)  

What is the primary disadvantage of the  pointer arrangement for indicating coil rotation?

What is used to find the value of a n unknown inductance?

C oil balance (Ans.)  (Ans.) 

In a regulated power supply, sup ply, 'current limiting' is sometimes used to:

(Ans.)   I nduc nducta tance nce b brr i dge (Ans.)

What component of the D’Arsonval D’ Arsonval meter movement completes the circuit for current

minimize short-circuit through the regulator regulator current (Ans.) (Ans.)   passing

The _______ of the voltmeter is always given on the voltage charts for a particular piece of equipment.

flow to the coil?

Hairspring (Ans.)  (Ans.) 

The purpose of a series pass transistor in a regulated power supply is to:

 se  sensitiv nsitivii ty (Ans.) (Ans.)  

What component supplies restoring force to the coil of the D’Arsonval meter movement?  movement? 

mai mai ntai ntain n the output volta voltagg e at a constant value (Ans.)  (Ans.) 

(Ans.)   Hairspring (Ans.)

What are the two main categories of maintenance?

What type of maintenance is used to isolate troubles by means of test techniques and  practices that that realign or readjust eequipment quipment or otherwise bring the equipment back up to  proper performance?

Pr eventive eventive and corr ec ecti tive ve maintena maintenance nce (Ans.) (Ans.)  

(Ans.)   C orr ective ma maii nte ntenance nance (Ans.)

What type of maintenance involves isolating equipment trouble and replacing r eplacing defective  parts?

What type of maintenance consists of checks to determine whether equipment is functioning  properly?

(Ans.)   C orr ective ma maii nte ntenance nance (Ans.)

Preventive maintenance (Ans.)  (Ans.) 

What advantage is gained by using pole pieces with curved faces in the th e D’Arsonval meter movement?

 Makes it possible  Makes ssible to ha havve a more linea linear sca scale than if the poles were flat (Ans.) (Ans.)   What structurally large, low-resistance conductor is connected in parallel with the meter movement to prevent damage?

 Shunt (Ans.)  (Ans.)   Which quantity determines the intensity of an electric shock?

Current (Ans.)  (Ans.)  On what range should you set s et the voltmeter  prior to taking a voltage voltage measurement?

(Ans.)   Highest (Ans.) What tool is used to de-energize capacitors in a circuit that has been disconnected d isconnected from its  power source?

What term is used to describe the work done t o correct, reduce, or counteract wear and damage to equipment?

 Maintena  Mainte nanc nce e (Ans.) (Ans.)  

increase current flow?

 Zero-t  Ze ro-te emperature rature coe coeffi fficie cient nt (Ans.)  (Ans.) 

What system is designed to standardize the recall and scheduling of test, measurement, and diagnostic equipment into calibration facilitiess and ffor facilitie or the documentation of actions  performed by the calibration calibration facili facility? ty?

The ______ of a capacitor is important  because it is is an indication of the va various rious losses of a capacitor.

 po  power fa fact cto or (Ans.)  (Ans.) 

Ground (Ans.)  (Ans.)  How is ammeter connected with the circuit under test?

I n seri seri es (Ans.)  (Ans.)  What must be done to a circuit before you can use an ohmmeter for testing?

I t must be de de-ene -enerr gi zed zed (Ans.)  (Ans.)  What term is used to express the sensitivity of a voltmeter?

A good choice of shunt resistance r esistance will place the indicating pointer near what part of the meter scale with a normal load?

 Mi dsc sca ale (Ans.)  (Ans.) 

 ME AS ASUR UR E syste system (Ans.)  (Ans.) 

 Shorting  Sho rting prob probe e (Ans.)  (Ans.)  When taking a voltage measurement, which lead of the voltmeter should you connect to the circuit first?

What type of temperature coefficient material does not produce increased heat in response to

The evaluation of the performance of an equipment compared to your knowledge of how the equipment should operate with the way it is actually performing is known as  ________.

troubleshooting (Ans.)  (Ans.)  What is a data processing system designed to  provide a standardized standardized system for the recall and scheduling of t est, measurement and

9

In what manner are current-measuring instruments connected to a circuit?

(Ans.)   I n seri seri es (Ans.) An ammeter should always be connected so that current will flow into what terminal and out of what terminal?

Negative, positive (Ans.) (Ans.)   What condition exists when the insertion of a meter into a circuit changes the operation of the circuit?

 Mete  Met er-load r-loadi ng (Ans.)  (Ans.)  What modification is made to the D’Arsonval meter movement to enable the meter to measure voltage?

 

Excel Review Center  A mult multime imete terr (high (hig h res resista istanc nce e) is place laced d in  se  seri ri es with th the e coi coi l of tthe he meter. (Ans.)  (Ans.) 

ECT Coaching TH What type of circuit where two conductors touch each other directly or through another conducting element?

What factors determine the value of the th e multiplierr resistor? multiplie

(Ans.)    Short  Sho rt circuit (Ans.)

The curr cur r ent requir requir ed for full-sca full -scale le de deflect flectii on, and the rang r ange e of the voltage to be mea measur sur ed (Ans.)   (Ans.)

 Manganin  Manga nin (Ans.)  (Ans.) 

In what manner are voltage-measuring v oltage-measuring instruments connected to the circuit to be measured?

I n par par allel (Ans.) (Ans.)  

Shunts are usually made from what alloy?

What property of shunt is desired d esired because of the heavy currents that often flow though shunts producing heat?

(Ans.)    Zero-t  Ze ro-te emperat rature ure coe coeffi cie cient nt (Ans.)

A _______ is a single meter that combines the functions of a dc ammeter, a dc voltmeter, an ac ammeter, an ac voltmeter, and an ohmmeter.

(Ans.)    Multime  Multim eter ter (Ans.) What is used in sensitive electronic circuits where only extremely small amounts of energy can be extracted without disturbing the circuits under test, or causing them to be inoperative?

E lect lectrr onic onic Di gi tal tal M ult ultii meter ter (Ans.)  (Ans.) 

What is used to measure very low currents, such as those in bridge circuits and is considered as the highest sensitivity of any of

What is a precision pr ecision piece of test equipment used to compare an unknown voltage with an internal reference voltage and to indicate the

resistance circuit, you should always use a voltmeter with what relative value of resistance?

the various types of meters in use today?

difference in their values?

High (Ans.)  (Ans.) 

In D’Arsonval meter, many turns of fine wire would be used, each turn adding more effective length to the coil. The coil is wound on an aluminum frame called _______.

What is used to measure the beta of a transistor, the resistance appearing at the electrodes, and the reverse current of a transistor or semiconductor diode?

When making voltage measurements in a high-

What instrument is used for measuring the insulation resistance of cables?

 Megohm  Mego hmm mete terr (me (megger) (Ans.)  (Ans.)  What added features enable a dc milliamme milliammeter ter to function as an ohmmeter?

1. A source sour ce of of dc pot potent entii al (Ans.)  (Ans.)   2. One or mo more res resisto istors rs (one (one of which which is variable) (Ans.) (Ans.)  

(Ans.)   G alvanom alvanomete eterr (Ans.)

D i ff ffe er ential Voltme Voltmeter ter (Ans.)  (Ans.) 

 Semicond iconduc ucto torr Test Test Se Sett (Ans.) (Ans.)  

Bobbin (Ans.) (Ans.)   What is in megger that are designed to slip if the generator is cranked faster than its rated speed and prevents the generator speed and output voltage from exceeding rated values?

The multimeter that contains circuitry that allows it to be used as a voltmeter, an ammeter or an ohmmeter is called _______.

Volt-Ohm-M Volt-Ohm -Mii lliamm lliammeter ter (V OM) (Ans.) (Ans.)  

(Ans.)   F r i cti cti on clut clutche chess (Ans.) What are the advantages of a VOM?

A full-scale deflection on an ohmmeter o hmmeter scale indicatess what resistance between the leads? indicate

 Zero  Ze ro (Ans.) (Ans.)  

A resistor placed in parallel with the meter terminals and used to provide prov ide increased range capability?

 Mete  Met er shunt shunt (Ans.)  (Ans.)  The R x 100 resistance selection on an ohmmeter has what amount of resistance compared to the R x 10 selection?

What is one of the greatest advantages of a VOM?

1/10 (Ans.)  (Ans.) 

(Ans.)   N o exter external nal p pow owe er source is i s rreq equi uirr ed (Ans.)

What is the purpose of the guard ring in the megohmmeter?

Before you connect a VOM in a circuit for an ohmmeter reading, in what condition must the circuit be?

 Shunt lea leakage curren current, t, which prev reve ents nts fal false se readings (Ans.) (Ans.)   Most meggers you will use are rated at what voltage?

 500 (Ans.) (Ans.)  

De-energized (Ans.) (Ans.)   When taking resistance reading with a VOM, you will obtain the most accurate readings at or near what part of the scale? s cale?

(Ans.)    Mi dsc sca ale (Ans.) The development of excessive test voltages is avoided by the use of meggers equipped with what device?

F ri cti cti on clut clutche chess (Ans.)  (Ans.)  What components in an electrodynamometertype meter movement produce the magnetic field?

F i xed co coils ils (Ans.)  (Ans.) 

 Si  Sizze of sp spir al cond conduct ucting ing (Ans.)  (Ans.)  What is the primary advantage of the electrodynamometer-type electrodynamome ter-type meter over the D’Arsonval type meter?  meter?  

T he electrodynam electr odynamome ometer ter-type -type me meter ter can be used to mea measur sur e both both ac and d dcc cur r ents (Ans.)   (Ans.) What test is used to check for opens (or to see if the circuit is complete or continuous) and is accomplished with an ohmmeter?

The multimeter has two selector switches. The switch on the lower center is the ________ switch.

range (Ans.)  (Ans.)  The multimeter is equipped with a pair of test leads. What is the ccolor olor of the positive le lead? ad?

R ed (Ans.) (Ans.)   What is the color of the negative lead of the multimeter?

Polarity (Ans.) (Ans.)  

Black (Ans.) (Ans.)  

Power for the electronic digital multimete multimeterr is

What is an important point to remember when

normally supplied by what internal power source?

you are making an accurate resistance measurement? “Zero” the meter each time you select a new range (Ans.) 

How is an overload condition indicated by the electronic digital multimeter? Simultaneous flashing of display readouts (Ans.) (Ans.)   In an electronic digital multimeter, the digital information is displayed by what type of numerical readouts?

(Ans.)   L i ght-em ght-emii tti tti ng diod diode es (Ans.) What structurally large, low-resistance conductor is connected in parallel with the meter movement to prevent damage?

When using OUTPUT, do not attempt to use the meter in a circuit in which the dc voltage component exceeds the ______ rating of the  blocking capacitor.

(Ans.)   400-volt (Ans.) What are the things to do when using the th e multimeterr as a current-indicating instrument? multimete

1. N eve everr connect the test test leads leads dir ect ectly ly across a voltage (Ans.)  (Ans.)   2. Always Always co conne nnect ct th the e instrume instrument in seri seri es with (Ans.)   the load (Ans.)

 Shunt (Ans.) (Ans.)  

(Ans.)   Continui ty Te Test st (Ans.) What is the general function of the differential What type of circuits are caused by some conducting part of the circuit making contact either directly or indirectly with the metallic structure of the ship or chassis?

The multimeter has two selector switches. The switch on the lower left is the ________ switch.  functio  func tion n (Ans.) 

Besides setting up the meter for expected voltage ranges, what must be strictly observed when taking dc voltage reading?

R echa echarr geab geable le batte batterr i es (Ans.)  (Ans.)  What is the limiting factors as to the amount of current an electrodynamometer meter movement can handle?

1. Porta Por tabili bility ty  2. Versatility Versatility  3. F ree reed dom fr fro om calibra calibratio tion n err ors ca caused used by agi ng tube tubes, s, li ne volta voltagg e vari variat atii on, and so  forth

voltmeter?

T o com compa parr e an an unk nown voltage voltage with a k nown reference ref erence vo voltage ltage and i ndi ndicate cate the dif difference ference i n thei thei r va values lues

Ground circuits (Ans.) (Ans.)   10

What is available for use with the multimeter and is primarily used to measure high-voltage, low-power, dc current sources, such as the anode supplies in television receivers and other cathode-ray tube circuitry?

D C hi highgh-vo volta ltage ge prob probe e (Ans.)  (Ans.) 

 

Excel Review Center What is the primary feature f eature of the differential voltmeter?

I t does does not not draw curr ent from fr om the unknown unknown  so  source urce for dc measu surem reme ent ntss when hen the the (Ans.)   measur measurem ement ent is obtain obtained ed.. (Ans.) To measure incident power, you must rotate the coupler-detector of the wattmeter so that the arrow indicating power flow points toward which end of the transmission line?

ECT Coaching TH Out- of-control Out-ofcontrol me mete terr s can be used on mo morr e than one elect electrr i cal cal or ele electroni ctronicc devi devi ce (Ans.) (Ans.)   How does a compass react when placed close to a current carrying conductor?

T he com compass pass needle needle swing swi ngss awa awayy fr om ma magn gnet etii c north and aligns alig ns itse i tself lf with the (Ans.)   ma magn gnet etii c ffii eld around the cond conducto uctorr (Ans.)

Load (Ans.)  (Ans.) 

If the amount of current in the conductor changes, what happens to the magnetic field around the conductor?

What condition produces the 10 kHz error signal generated by the metering bridge in the HP 431 C power meter?

I f the ccur urrent rent increa i ncrease sess the m magne agnetic tic fifie eld i ncr ncre eases, ases, i f the cur currr ent d dec ecrr ea eases ses the ma magn gnet etii c fi f i eld decrea decreases ses (Ans.)  (Ans.) 

 An unb unba alanc lance e in tthe he meteri ng bri dge (Ans.)  (Ans.)  In signal generators, what device is used to regulate the voltage of the output signal?

 Atte  Att enua nuato torr (Ans.)  (Ans.) 

How does the compass needle react to a decreased magnetic field?

T he comp compass ass nee n eedle dle wil willl not be de defl flecte ected d as (Ans.)    far from magnetic gnetic north north (Ans.)

What value does a meter movement react to (actually measure) when measuring ac?

 Average  Ave rage value value (Ans.) (Ans.)   What value is indicated on the scale of an ac meter?

(Ans.)   E ff ffe ective value value (r ms) (Ans.) What are three meter movements that can measure either ac or dc without the use of a rectifier?

E lect lectrr od odynam ynami c, movi moving ng vane and hot-wir e or (Ans.)   thermocouple (Ans.) What electrical property is used by b y all the meter movements?

Current (Ans.)  (Ans.) 

What electrical property does an ammeter measure?

Current (Ans.)  (Ans.)   Name the three three main sections o off a typical RFsignal generator?

What type of meter movement is the d’Arsonval meter movement?  movement? 

Osci llatorr cir Oscillato ci r cui cuit, t, modulat modulator or and outp output ut control circuit (Ans.) (Ans.)  

Per Perma manent-m nent-magnet agnet movi moving ng-coi -coill meter ter movement (Ans.) (Ans.)  

What is the function of the modulating circuit?

What is the effect of current flow through the coil in a d’Arsonval meter movement? movement?  

How does an ammeter effect the circuit being measured?

 A ma magne gnettic field field is ge gene nerat rate ed aroun round d th the e co coii l and the the a attraction ttraction of this thi s fi eld with the  pe  perma rmane nent nt magne gnett cause causess the the coil coil tto o move (Ans.)  (Ans.) 

 Si  Since nce th the e ammeter ter is a res resisto istorr in sse eri es with the load, load, iitt iincr ncrea eases ses the resistance resi stance of the (Ans.)   ci cirr cuit and and lowe lower s cir cuit curr ent (Ans.)

To produce produce an an A F (or video) video) si signal gnal that that ca can n be supe superr i mpo posed sed on the RF si sigg nal produced produced by the osci oscillato llatorr (Ans.)  (Ans.)  What frequencies are provided through t he  back-panel BNC? BNC?

1 MH z a and nd 10 MH z (Ans.)  (Ans.)  The LED lamps of a typical logic probe are normally in what state?

(Ans.)   DI M (Ans.) On the CRT display, what information is displayed in Quadrant 4?

Posi tive vvolt Positive oltage age (+V) (+V ) and ne negative gative current curr ent ( I ) (Ans.)  (Ans.)  When aligning the trace with a short applied to channel A, which control should be adjusted to  bring the trace parallel to the vertical axis?

Tr ace R ot otate ate Contr Control ol (Ans.)  (Ans.) 

What are the three functions of the hairsprings in a d’Arsonval meter movement? movement?  

1. T on return To retur poi i nter nte r toflow i ts rest p positi osition on when whe the therr eni sthe nopo curr ent (Ans.) (Ans.)    2. To oppose the the coil coil m mo ovem vement whe hen n th the ere is curr ent flo flow w (Ans.) (Ans.)    3. To prov rovide ide ele lect ctri ri cal cal conne connect ctions ions fo forr tthe he coil (Ans.)  (Ans.)  How would a compass react when placed close to a conductor carrying alternating current at a low frequency?

T he com compass pass needle needle would swing swi ng back back and  forth as the the curr curr ent cha change nged d from positive to (Ans.)   negative (Ans.)

What minimum voltage level can be attained in the pulse generator section by adjusting the LEVEL control?

How would the compass react if the alternating current through the conductor was a high frequency?

0 volts (Ans.) (Ans.)   What maximum voltage level can be attained

T he com compass pass needle needle would vibrate vibr ate r api api dly around ar ound the the zzeroero-cur currr ent poi poi nt ac me mete terr (magnetic (magne tic north) (Ans.) (Ans.)  

in the pulse generator section by adjusting the LEVEL control?

What is the purpose of a rectifie r ectifierr in a meter?

(Ans.)    5 volt voltss (Ans.) Medium 1 range is designed to check what resistance values?

 50 ohms hms to 10 kiloo kiloohm hmss (Ans.) (Ans.)   Two ways that circuit measurement is used?

C i r cuit cui t m mea easur sur ement ement i s used tto o (Ans.)  (Ans.)  1.   Monit  Monito or tthe he operat ration ion of a piec iece e of electri electri cal or ele electroni ctronicc equipment equipment  2.  D et etermi ermine ne the reason reason a piece pi ece of electri electri cal or elect electrr oni onicc equi equipm pmen entt is i s not  functio  func tioning ning prop prope erly Why are in-circuit meters used?

To moni monito torr the op ope er at atii on of electri electrical cal or or (Ans.)   electroni electronics cs devi devi ces (Ans.) What is one advantage of an out-of-control meter when it is compared with an in-circuit meter?

I t cha changes nges alt alte er nat natii ng curr en entt to pulsat pulsatii ng dir di r ect curr ent a and nd allows a dc m mete eter to me measur asur e ac (Ans.)  (Ans.)  How can d”Arsonval meter movement be adapted for use as an ac meter?

B y the use o off a rect rectii fier fi er (Ans.) (Ans.)   What is damping?  A process of “smoothing out” the oscillation oscillation

(Ans.)   i n a me meter ter moveme movement nt (Ans.) What are two methods used to damp a meter movement?

 As the the co coilil mo move vess throu through gh the the fi fie eld of tthe he  pe  perma rmane nent nt magne gnet, t, a curr curr ent is ind induc uce ed i n the coil opposi opposing ng the m move oveme ment nt of the coil; coil ; and a vane can be attached to the coil and  pla  p lace ced d in tthe he ir tight ig ht ch cha amber the so th tha at th the e movement of a the vane opposes movement of the coi coi l (Ans.)  (Ans.) 

How is an ammeter connected to the circuit under test?

I n seri seri es (Ans.)  (Ans.) 

How is the ammeter’s effect on the circuit  being measured kept kept to a minimum?

T he resi r esistance stance of the amme ammeter ter must be much (Ans.)    sma  sm aller ller ttha han n th the e circuit loa load. (Ans.) What is ammeter sensitivity?

Th The e am amount of of cur r ent that that will cause ful fulll scale deflect  scale flection ion (Ans.)  (Ans.)  What is used to allow an ammeter to measure different ranges?

(Ans.)    Shunt res resisto istorr (i(int nte ernal rnal or exte external rnal)) (Ans.) Why should you use the highest range of an ammeter for the initial measurement?

T o prevent pr event damage age to the meter meter moveme movement nt  fr  fro om excessive xcessive current current (Ans.)  (Ans.)  What range of an ammeter is selected for the final measurement?

 A range th tha at allow llows a meter rea read ding ne nea ar tthe he  center of the the scale (Ans.)  What are the safety precautions for the use of the ammeter?

1. A lway lwayss connect an amm ammete eter i n seri ser i es  2. Always Always st sta art with th the e highest highest range range  3. I n dc ammeters, ters, ob obse serve rve th the e prope roper p po olari lari ty 4. Deenegize and discharge the circuit before connecting conne cting or disconnec di sconnecti ting ng the am ammeter ter .  5. Neve Never use a dc ammeter ter tto o measure ac current 6. Observe the g ener ener al safety pr pr ec ecaut autii ons of electri electri c and elect electrr oni onicc devi devi ces Why will an a mmeter be damaged if connected in parallel with the circuit to be measured?

 Si  Since nce th the e ammeter ter has has a sm sma all res resii sta stanc nce e compa com parr ed to the load, load, i t will wil l h have ave ver ver y hi gh curr ent if i t is connecte connected in par par allel. allel. Thi T hiss hi higg h curr cur r ent wi wi ll damage the meter ter . (Ans.) (Ans.)   What electrical quantity is measured by a voltmeter?

(Ans.)   Voltage (Ans.) How is a voltmeter connected to the circuit to  be measured?

11

 

Excel Review Center (Ans.)   I n par par allel (Ans.) What is the loading effect of a voltmeter?

T he connection connection of a voltmeter voltmeter adds a r esista esistance nce in parallel arallel with wi th the cir cuit changi cha ngi ng the tot total al cir cuit r esi sista stance, nce, and loads loads the ccii rcui t (Ans.)  (Ans.)  How is loading effect of a voltmeter kept to a minimum?

 A vo voltm ltmete terr m must ust have have a high resist resista ance nce compa com parr ed to the cir cuit cui t bei bei ng me measured asured (Ans.)  (Ans.) 

ECT Coaching TH What area of an ohmmeter scale should be used when measuring circuits?

The middle of the scale (Ans.) (Ans.)   What are the two types of ohmmeters?

(Ans.)    Series and shun shuntt (Ans.) What is the most obvious difference between the two types of ohmmeters?

 Series ohmm hmmeters hav have 0 on th the e ri ght end of the scale scale and inf infii nity ni ty on the left end o off the  scale  sca le.. Shunt Shunt ohm hmm meters are are th the e opposite. site. (Ans.)  (Ans.) 

How is the mirror on a multimete multimeterr used?

 Make sure no ima image ge of th the e pointer inter is visi visib ble i n the mir mirrr or when reading reading the me mete terr (Ans.) (Ans.)   Why should you use a hook-on voltmeter instead of a multimete multimeter? r?

To measur measure e curr ent safely safely and easi easily ly (with ( with no need to disconnect need disconnect the wir wirii ng of the circuitr cir cuitry) y) (Ans.)  (Ans.)  What electrical quantity is measured by a wattmeter?

Power (Ans.) (Ans.)  

How is it possible to use a current sensitive

What are the safety precautions observed when

What electrical quantity is measured by a watthour meter?

meter movement to measure voltage?

using ohmmeters?

E ne nergy rgy (Ans.)  (Ans.) 

 Si  Sinc nce e th the e resista resistanc nce e of a meter mo move vem ment r em emai ains ns the same same a ass the poi pointer nter is i s deflected, deflected, the amount amount of cur r ent through thr ough the move moveme ment nt i s proporti proportional onal to the voltage voltage ap appli plied. ed. T herefor her efore, e, only the scale of the m move oveme ment nt (Ans.)   must be changed chang ed.. (Ans.) What is voltmeter sensitivity?

I t is i s an i nd ndii cation cation of the resistanc resistance e of of the meter meter expr expressed essed i n ohms per volt. T The he total total r esistance o off the met meter er iiss the sensi sensitivi tivity ty (Ans.)   multi ultipli plied ed by the full-scale full- scale vvolta oltage. ge. (Ans.)

1. D eenergi nerg i ze and discharg discharge e tthe he ccii r cuit before connecting connecting an ohm ohmme mete terr  2. D o not not apply power to to a circuit while measuring asuri ng r esi sista stance nce  3. Switc Switch h ohm hmm meter ter to to the the OF F po positio sition, n, if  prov  provide ided d, or or to to highes highestt range and rem remo ove meter meter lea l eads ds fr om the m mete eter when fifini nished shed measuring asuri ng r esi sista stance nce 4. A djust the ohm ohmm meter ter after changing changi ng r esistance r ange an and d before before m me easuri ng reading indicates the resistance What is the primary use of a megger?

What are the two types of frequency meters?

V i brati brati ng r ee eed da and nd movi ovi ng disk di sk (Ans.)  (Ans.)  What is used to monitor the operation of a  piece of electrical electrical or electronic equipment and determine the reason the equipment is not n ot functioning properly?

Circuit measurement (Ans.) (Ans.)   What is a condition in which some point in the circuit, where full system voltage is present, p resent, comes in direct contact with the ground or return side of the circuit?

What method is used to allow a voltmeter to have several ranges?

(Ans.)   To measure high resistance (Ans.)

The use of resistors in series with the meter movement (Ans.)  (Ans.) 

What is the procedure for using a megger to check the insulation of a conductor?

Why should you always use the highest range

C onnect one lead lead to the i nsul nsulation ation and one lea lead d to the conduc conducto torr . Tur n the handcrank

What is described as a condition that is not a direct short but in which circuit current increases beyond the designed current carrying

when connecting a voltmeter to a circuit?

(Ans.)   until i t sta starr ts tto o sli slip. p. Note the r ea eading ding.. (Ans.)

ability of the circuit?

To prev pr event ent e excess xcess cur r ent thr through ough the mete meterr movement (Ans.)  (Ans.) 

(Ans.)   D i rect short short (Ans.)

What is a normal indication on a megger when checking insulation?

What type of meter movement reacts to voltage rather than current?

I nfinit nfinityy (Ans.)  (Ans.) 

E lectrost lectrostat atii c (Ans.)  (Ans.) 

What are the safety precautions observed when using a megger?

What is the only use for the voltage v oltage sensitive meter movement?

H i g h-voltage h-voltage me measureme asurement nt (Ans.) (Ans.)   What electrical quantity is measured by an ohmmeter?

R esistance (Ans.)  (Ans.)  What are the safety precautions for the use of voltmeters?

1. A lways connect a voltme voltmete terr i n par par allel  2. Alwa Always ys sta start with th the e highe hig hest st range  3. Dee Deene nerg ize andi ng discha ischarg th the e circuit be befor fore ergco connect nnecti andrge di diesconnecting sconne cting the voltmeter 4. I n a dc voltme voltmete terr , obser obser ve pr pr op oper er polar polar i ty  5. Nev Neve er use a dc vo volt ltm mete terr tto o measure ac voltage 6. Observe the gene generr al safety pr pr ecaut ecautii ons of electri electri c and e elect lectrr onic de devi vice cess What other measurement can an ohmmeter make?

Ci r cuit ccon ontinuity tinuity (Ans.)  (Ans.)  How is a series-type s eries-type ohmmeter connected to the circuit being measured?

The ohmmet ohmmeter er i s connected iin n seri ser i es with wi th the r esi esistance stance to be be m mea easur sur ed (Ans.) (Ans.)   What is used to provide the ohmmeter with several range?

 An ohmm ohm mand ete terrahas ha si tch se seve veral inte r esistors sw swi or oral r ainternal se serr irnal es ofrange jacks j acks to (Ans.)    se  sele lect ct th the e prope roper range range (Ans.)

1. Use meggers meggers fo f or hi ghgh-rr es esii stance stance measur measur em ement ent only.  2. Nev Neve er to touch uch the the test le lea ads whe hen n th the e ha hand ndle le i s be beii ng cr cranke anked d  3. Dee Deene nerg rgize ize and discha ischarg rge e th the e circuit completely before connecting a megger 4. D i sconnec sconnectt the i tem tem b being eing checke checked d fr from om other other cir cuits, if i f po possi ssib ble, be before usi using ng a megger What is a multimeter?

 A single meter de device cap capable of pe perf rfo orming the functions functi ons of and a dcammeter voltme voltmeter terand andan ammet ammeter, er, an ac voltmeter amme ter ohmmeter. ohmme ter. (Ans.)  (Ans.) 

E xce xcessive ssive curre curr ent (Ans.)  (Ans.)  What is described as a condition in which the heat in or around a circuit increase increasess to a higher than normal level?

(Ans.)   E xcessi xcessive ve heat heat (Ans.) What are the two types of circuit protection devices?

F use and Ci r cuit Br eaker aker (Ans.) (Ans.)   What type of fuse allows surge currents without opening? They are used to protect motors, solenoids and transformers.

Delay fuses (Ans.)  (Ans.)  What type of fuse have neither a time delay nor a fast acting characteristic. They are used in automobiles, lighting circuits and electric electrical al  power circuits?

 Stand  Sta nda ard fuse (Ans.) (Ans.)   What are the reasons circuit control is needed?

Why is a multimeter preferred over separate meters?

I t is is much mo morr e co conveni nvenient ent to to have one mete meter with sever al functions fun ctions than sev s eve er al me mete terr s each each with a si single ngle function. (Ans.) (Ans.)   How is a multimeter changed from a voltage measuring device to a resistance r esistance mea measuring suring device?

B y cha changi ngi ng the p pos osii tion of the function (Ans.)    switch (Ans.)  switch Why is the dc scale on a multimete multimeterr differ than the ac scale?

T he me meter ter moveme movement nt reacts r eacts to average averag e ac voltage volt age and curr ent a and nd the e eff ffec ecti tive ve value value is desired. (Ans.)  (Ans.)  What is the reason for having a mirror on the scale of a multimeter?

To stop parallax error (Ans.)  (Ans.)  12

1. To T o remove remove powe powerr fr om a malfu malfuncti nction on devii ce dev  2. To remo remove power from a device you you wish to to work on and restore pow power er when the work work i s completed completed  3. To tu turn rn de devices vices on and off a ass th the e device is needed 4. To sele select ct tthe he function or ci r cuit desi desirr ed withi n a dev devii ce What are the three types of circuit control devices?

 Switche  Switc hes, s, Sole Soleno noids, ids, and R elay lays (Ans.)  (Ans.)  What is the difference between manual s witch and an automatic switch?

 A m nua l sw switch mus ust tati bei ctu turne rned d otur n ans ndaoff byma aape pnual er son. Aitch n autom auto m at switch ci cirr cui cuitt on and and o off ff without the the action action of a  p  pe erson (by using mech cha anical nical or e ele lect ctri ri cal cal (Ans.)   devices) (Ans.)

 

Excel Review Center Which one is an example of a manual switch? s witch?

 A light sw switch itch,, an ig ignition nition sw switch itch,, tte ele levvisio isi on channel selector selector (Ans.) (Ans.)   Which one is an example of automatic switch?

 A the thermo rmost sta at, an aut uto omobile distribut istributo or, a lim li mit switch (Ans.)  (Ans.)  Why are multicontact switches used?

 Multiconta  Multicont act sw switch itche es make possible ssible the the control of mor mor e tthan han one ci cirr cui cuitt or or the  se  sele lect ction ion of one one of seve several ral possible ssible circuits with a single sing le sw swii tch (Ans.) (Ans.)   What classification classification of a switch is used when you describe it as a rocker switch?

(Ans.)   T he type of actuator (Ans.)

ECT Coaching TH (Ans.)   I t incre i ncrea ase sess (Ans.)

What is the movement of aluminum wire away from a point where pressure is applied? app lied?

What is the operating principle of a relay?

The Th e magnetic ffii eld cr crea eate ted d in a coi coi l of wir e will wi ll attract aft ar arma matur ture e ca causi usi ng a move moveme ment nt i n sets of conta contacts. cts. (Ans.)  (Ans.) 

(Ans.)   C lappe lapperr r elay elay (Ans.)

T he soleno solenoii d pr pr ovides a mechani mechanical cal mo movem vement ent of a plu plung nger er (a movea moveable ble core) while whil e the the core core of a r ela elayy is ffii xed. (Ans.)  (Ans.) 

A relay is described by what type of enclosure?

OPEN, SEMI SEALE D, o orr SEALE D (Ans.)  (Ans.)   What are the two classific classifications ations of rrelays? elays?

C ontrol rela r elays ys and po powe werr r elays (contracto (contractorr s) (Ans.)  (Ans.)  How can you determine if a relay is operating op erating (changing from one position to the other)?

B y ob obser servi ving ng the m move oveme ment nt of the conta contacts cts if if the relay is i s open open or sea s ealed led w wii th a transparent transpar ent coverr . I f the relay ha cove hass an op opaq aque ue co cove verr , you

Two-position (Ans.)  (Ans.) 

can “feel” the operation of the relay by

 pla  placing cing yyo our finger finger o on n the the cove cover. r. (Ans.) (Ans.)  

Three-position (Ans.)  (Ans.)  What type of switch should be used to control a circuit that requires a temporary a ctuation signal?

 A mo moment nta ary sw switch itch (Ans.)  (Ans.)  What type of switch is used if it is necessary to guard against a circuit being a ccidentally turned on or off?

 A locke locked-p d-po osition sw switch itch (Ans.)  (Ans.)  What is the common name used for an accurate snap-acting switch?

(Ans.)    A micr micro osw switch itch (Ans.) What is the current rating of a switch?

The maxi maxi mum cur currr ent a swi swi tch is i s de desi sigg ned to carry (Ans.) (Ans.)   What is the voltage rating of a switch?

T he maxi maxi mum voltag voltag e a allowab llowable le in i n the (Ans.)   cir cuit iin n which the switch is i nstalled nstalled(Ans.) What two types of meters can be used to check a switch?

 An ohm ohmm mete terr a and nd a vo volt ltm mete terr (Ans.)  (Ans.) 

What item should be checked on a relay that is not operating properly?

The Th e co coii l sh should ould be checked checked for opens, opens, shor shorts, ts, or a short to ground; gr ound; termi terminal nal lea leads ds should be checked checked for char charrr ed or burned bur ned i nstalla nstallation; tion; the co conta ntact ct surface sur facess sshould hould be be checked for fi lm, carbon, ar ar cing ci ng and co conta ntact ct (Ans.)    spa  spacing (Ans.) What is used to clean the contacts of a relay?

 A burnishi burnishing ng too tool (Ans.)  (Ans.)  What tool is used to set contact clearances on a relay?

(Ans.)    A po point bende nder (Ans.) The ______ of a switch s witch is the position of the switch which is moved to cause the switch to change contact position.

The channel selector on some TV sets is a multilayer rotary switch. This is called ___ _.

(Ans.)   wafer switch (Ans.) In a wafer switch, each layer is known as a___. a_ __.

Wafer (Ans.) (Ans.)   What is the reason for the establishment of a “unit size” for conductors?  conductors?  

T o allow comp compari ari sons betwee between n conductors of different sizes and resistance (Ans.) (Ans.)   A circular conductor with a diameter of 1 mil and a length of 1 foot is called ______.

(Ans.)   mil-foot (Ans.) What is the circular mil area of a 19-strand conductor if each strand is 0.004 inch?

 304 mils (Ans.)  (Ans.)  What is the resistance of one unit of volume of a substance?

 Specifi  Spe cificc res resista istanc nce e (Ans.) (Ans.)   What factors are used to calcula calculate te resistance of a particular conductor in ohms?

1. Le L ength  2. Cr oss-se ss-sect ctiona ionall area  3. Specifi Specificc res resista istanc nce e of a unit volum volume e of tthe he  subst  sub sta anc nce e from which th the e cond conduc ucto torr is made

 Actua  Actu ator (Ans.)  (Ans.)   The ______ of a switch s witch refers to the number of  points at which the actuator can select a contact configuration?

Number of positions (Ans.)  (Ans.)   What position of a switch is one in which the actuator will only stay as long as force is applied to actuator?

(Ans.)    Mome  Mom enta ntary po position (Ans.) If a switch must be checked with pure pur e applied, what type of meter is used?

What position of a switch is used to prevent the accidental movement of the actuator to or from a specific position?

What should you check when performing  preventive maintenance maintenance on a switch switch??

Locked position (Ans.)  (Ans.) 

The switch swi tch op operation eration for f or smo s mooth oth and and correc corr ectt op ope er at atii on, the te terr mi nals for corr cor r osion, and the physi physical cal co conditi ndition on of the swi swi tch (Ans.) (Ans.)  

What switch is one in which the movement of the switch contacts is relatively independent of the actuator movement?

 A vo voltm ltmete terr (Ans.)  (Ans.) 

What relay uses clapper (armature) to move contact positions and accomplish the switching of circuits?

How does a relay differ from a solenoid? s olenoid?

In describing a switch by the number of  positions of the actuator, actuator, what are the two  possible configurations configurations for a single-pole?

In describing a switch by the number of  positions of the actuator, actuator, what are the two  possible configurations configurations for a single-pole?

 Aluminum  Alum inum cree creep (Ans.)  (Ans.) 

 Snap  Sna p-act -acting ing sw switch itch (Ans.)  (Ans.) 

When using an American Standard Wire Gauge to determine the size of a wire, where should you place the wire in the gauge to get the correct measurement?

I n the parallel parallel walled walled slot not tthe he cir cular (Ans.)   area ar ea(Ans.) What are the factors you should use to select s elect wire for a specified current rating?

1. Conductor size  2. The materi teri al it is ma made  3. lo cattof ioniinsulation of tthe he wirused e in a circuit 4. The TThe he loca type type nsulation What are the three types of nonmetallic insulating materials materials that can be used in a hightemperature environments?

1. FE P  2. E xtrud xtrude ed polyte lytetra trafluo fluoroe roeth thyylene lene  3. Silico Si licone ne rubbe rubber

What is the operating principle of solenoid?

The magn magnet etii c field fi eld cr crea eate ted d i n a coi coi l of wir e and cor cor e w wii ll att attrr ac actt a soft ir on plung plunger er when curr ent flows flows through the coil. (Ans.)  (Ans.)  If a solenoid is not operating properly, what item should be checked?

The connecti connecti ons, the plunger plunger,, the mechanism mechanism that the the sole solenoid noid actua actuate tes, s, the energ energii zing (Ans.)   voltage, and the coil of the solenoid (Ans.) What is one example of the use of a solenoid? s olenoid?

(Ans.)    A sta starte rterr mo motor and and so sole leno noid id (Ans.)

What happens to the resistance of copper when it is heated?

A ______ is an accurate snap-acting switch and the operating point is preset and very accurately known.

Why is it important for you t o consider the ambient (surrounding) temperature of a conductor when selecting wire size?

(Ans.)   microswitch (Ans.)

Th The e heat heat sur r oundi oundi ng the conducto conductorr i s an i mpo porr tant tant par par t of tota totall cond conducto uctorr heati heating ng (Ans.)  (Ans.) 

What will happen if the current carried by the switch is higher that the current rating?

T he contact contactss of the switch will wi ll melt and weld weld together (Ans.)  together (Ans.) 

What are the advantages of using aluminum wire for carrying electricity over long distance?

What control device uses electromagnetism to convert electrical energy into a mechanical motion?

(Ans.)   I t is light li ght and reduce reducess chr chrom oma (Ans.)

(Ans.)    Soleno  Sole noid id (Ans.)

What are the advantages of copper over aluminum as a conductor?

1. I t ha hass hi higher gher conduct conductii vity 13

 

Excel Review Center  2. I t is mo more duct uctile  3. I t has has rela relatively ively high hig h te tens nsile ile stren strength gth 4. I t can be easi easily ly solde solderr ed The amount of increase in the resistance of a 1-ohm sample of the conductor per degree of temperature rise above 0oC is called ________.

ECT Coaching TH (Ans.)   G alvanom alvanomete eterr (Ans.) The process of applying thin coat of solder to materialss prior to their b material being eing soldered.

Tinning (Ans.)  (Ans.)  The addition of atmospheric oxygen to metal to form rust, or to cause a breakdown in the internal construction of the metal.

What is component 6 in figure T2?  T2? 

The resistance to current leakage through the th e insulation is called ______.

Oxidation (Ans.) (Ans.)  

apac acii to torr - A ns. C ap

I nsulati nsulati on resistanc resistance e (Ans.)  (Ans.) 

A continuous jacket of lead molded around a single-conductor or multiple-conductor cable.

What is component 8 in figure T2?  T2? 

What is the ability of the th e insulation material to withstand potential difference?

L ea ead dS Shea heath th (Ans.)  (Ans.) 

(Ans.)   Dielectric strength (Ans.)

What do you call the force exerted on an insulator by the voltage in a conductor?

How is dielectric strength of an insulator determined?

E lectrost lectrostat atii c stress (Ans.)  (Ans.) 

B y raisi r aisi ng the voltage voltage on on a test test sample sample unti untill it it breaks down (Ans.)  (Ans.) 

The discharge of electrici electricity ty from a conductor with a high potential. p otential.

nsforme rmerr - Ans. Tr ansfo

Corona (Ans.) (Ans.)  

What type of switch is represented by T2?? component 3 in figure T2

(Ans.)   Temperature Coefficient of Resistance (Ans.)

What safety precaution should you take when working with extruded  polytetrafluoroethylene?  polytetrafluoroethyle ne?

 Avoid breath  Avoid reathing ing th the e vapors whe when n the the i nsulation iiss heate heated d (Ans.)  (Ans.)  What is the purpose of coating a copper conductor with tin when rubber insulation is used?

To prev pr event ent the rubbe rubberr i nsulation nsulati on from fr om (Ans.)   de dete terr i oratin oratingg due to to chemi chemi cal acti acti on (Ans.)

What is component 9 in figure T2?  T2? 

A device used to absorb heat and prot ect heatsensitive components during soldering.

What is component 4 in figure T2?  T2? 

 Si ngle-p  Single -po ole single single-th -throw row - Ans.

A material that removes oxides from surfaces s urfaces to be joined by soldering or welding.

Flux (Ans.)  (Ans.) 

What is the most common insulators used for extremely high voltages?

(Ans.)   Thermoplastic (Ans.)

What is the common name for enamelinsulated wire?

The capacity of a soldering iron to generate and maintain a satisfactory soldering temperature while giving up heat to the material being soldered.

(Ans.)    Magnett wir e (Ans.)  Magne

V ari able resisto resistorr - Ans.

(Ans.)   H eat eat shunt (Ans.)

A synthetic mixture of rosins that is flexible and used as an insulating material. Generally used as an insulator for low- and mediumrange voltages.

Varnished cambric and oil-impregnated  pa  paper (Ans.)  (Ans.) 

emi tt ttii ng di di od ode e - Ans. L i ght em

What is component 3 in figure T3?  T3? 

V ari ariab able le i nd nduct uctor or - A ns.

Thermall ine Therma i nerr tia (Ans.) What is component 4 in figure T3?  T3? 

What is the standard unit of measurement for a round wire cross-sectional area?

Ci rcula rcularr mil (Ans.)  (Ans.)  What term is general one and usually applies only to the larger sizes of conductors?

What is the name of an electrical wiring diagram that uses standard component symbols?

 Sche  Schem matic - Ans. Ans.

Which is accurately represented in electrical schematics?

What is used in measuring wires ranging in size from number 0 to number 36?

The way components are interconnected - Ans.

 Ameri  Ame ri can can Sta Stand nda ard Wir e Gauge (Ans.)  (Ans.)  What is the reciprocal of conductivity?

Resistivity (Ans.)  (Ans.) 

Which device or circuits changes an alternating current into a varying direct current signal?

What is the area in circular mil of a 12-gauge wire that has a diameter of 80.81 mils?

A rectangular conductor is 1.5 inches wide and 0.25 inch thick. What is its area in square mils?

 375,00  375 ,000 0 squa square re mils (Ans.)  (Ans.)  What is defined as t wo concentric wires, cylindrical in shape, separated by a dielectric of some type?

C oaxi oaxi al cable cable (Ans.)  (Ans.)  The weaving of metal or cloth material as an outer coating to a cable that prevents cable damage from moisture and rough treatment is called ______.

(Ans.)   braid (Ans.)

What do the symbols on an electrical schematic represent?

E lec lectri tri ca call com compo pone nents nts - Ans. An s.

Cable (Ans.)  (Ans.) 

6,530 circular mils (Ans.)  (Ans.) 

 Antenna  Antenna - Ans.

What is component 1 in figure T1?  T1? 

sistorr - A ns. R esisto

R ect ctififier ier - Ans. What is a relay?

What is component 2 in figure T1? T1?  

nsistorr - Ans. Tr ansisto What is component 3 in figure T1?  T1? 

L amp - Ans. What is component 4 in figure T1?

B at atte terr y - A ns.

 An e ele lect ctri ri ca cally lly-co -cont ntroll rolle ed sw switch itch - Ans. Which displays an electrical quantity as a numeric value?

 Mete er - Ans.  Met What type of circuit controls the amount of voltage from a power po wer supply?

. Regulato Regulatorr - Ans.

What is the function of component 2 in T1?  Figure T1? 

C ont ontrr ol the flow of curr cur r ent - Ans. A ns.

A meter used to measure small values of current by electromagne electromagnetic tic or electrodynamic means is called ______. 14

What component is commonly used to change 120V AC house current to a lower AC voltage for other uses?

Tr ansfo nsforme rmerr - Ans.

 

Excel Review Center Which is commonly used as a visual indicator?

ECT Coaching TH

E nsur nsure e tha thatt the the cir cui cuitt is not po powe werr ed  Ans.

What kind of hazard might exist in a  power supply when it is turned off and disconnected?

Which precaution should be taken when measuring high voltages with a voltmeter?

mi ght r ece ceii ve an elec electri tri c shock fr f r om Y ou mi the charg charge e sto storr ed i n large larg e ca capa paci cito torr s  Ans.

Ans.. LE D - Ans Which is combined with an inductor to make a tuned circuit?

Cap Capac acii to torr - A ns. What is the name of a device that combines several semiconductors and other components into one package?

I nt nte egr gra ate ted d cir circuit cuit - Ans.

E nsu nsurr e that the voltme voltmeter ter and leads leads are rated for use at the voltages to be measured me asured - Ans. A ns. Which is a safety hazard of a 12-volt storage battery?

 Shorting rting the the termina rminals ls ca can n ca cause use burns,  Sho  fire  fi re,, or or an an exp xplo losio sionn- Ans.

Which is a resonant or tuned t uned circuit?

 An induc and a ca cap pacito citorr conne connect cte ed inducttor and i n ser ser i es or or parallel parallel to for form m a fi lte lterr  Ans. Which is a common reason to use shielded wire?

T o preve prevent coupli coupling ng of unwanted unwanted sign si gnals als to or from the wire- Ans. Which instrument would you use to measure electric potential or electromotive force?

volt  A vo ltm mete terr - Ans. What is the correct way to connect a voltmeter to a circuit?

What health hazard is presented by electrical current flowing through the  body? A. It may cause injury by heating tissue B. It may may disrupt the electrical functions of cells C. It may may cause iinvolunt nvoluntary ary m muscle uscle contractions

D . A ll of of these these choices are corr corre ect  Ans. What is the purpose of a fuse in an electrical circuit?

T o i nterr upt po powe werr i n case case of ove overr load  Ans.

When should members of a tower work team wear a hard hat and safety glasses?

 At a all ll time imess whe hen n any work is i s being do done on the to towe werr - Ans. A ns. What is a good precaution precaution to observe  before climbing climbing an antenna tower?

P ut on a car car efu fully lly inspe i nspecte cted d climbi climbi ng harne harn ess (fall (f all ar ar r este sterr ) and safe safety ty  glass  gla sse es - Ans. Under what circumstances is it safe to climb a tower without a helper or observer?

verr - Ans. N eve Which of the following is an important safety precaution to observe o bserve when putting up an antenna tower?

L oo ookk for and stay stay clear clear of any over over hea head d ele lect ctrr i ca call wi wi r es - Ans. What is the purpose of a gin pole?

I n paralle parallell wi wi th the cir cuit - Ans. A ns.

Why is it unwise to install a 20-ampere fuse in the place of a 5-ampere fuse?

T o lilift ft towe towerr secti secti ons or antennas antennas - Ans. A ns.

How is a simple ammeter connected to a circuit?

E xcessive cur currr ent could could ca cause use a fi r e  Ans.

What is the minimum safe distance from a  power line to allow when installing installing an antenna?

What is a good way to guard against electrical shock at your station? A. Use three-wire cords and plugs for all AC powered equipment B. Connect all AC powered station equipment to a common safety ground C. Use a circuit circuit protected by a groundfault interrupter

E nough so s o that that if the ant ante enna falls unexpectedly, no part of it can come closer than 10 fe f eet to the po powe werr wir es  Ans.

seri es wi wi th the cir circuit cuit - Ans. A ns. I n seri Which instrument is used to measure electric current?

 An am terr - Ans. ammete What instrument is used to measure resistance?

ohmm  An ohm mete terr - Ans.

D . A ll of of these these choices are corr corre ect - Ans. A ns. Which might damage a multimeter?

 Atte to measure volt lta age whe hen n  Attempting to usingg the r esistanc usin sistance e se sett ttii ng - Ans. A ns. Which measurements are commonly made using a multimeter?

oltage ge and r esi sista stance nce - Ans. A ns. V olta Which type of solder is best for radio and electronic use?

Which of these precautions should be taken when installing devices for lightning protection in a coaxial cable feed line?

 Moun  Mountt all of the the prot rote ect cto ors on on a meta tall  pla  p late te tha hatt is in turn co conne nnect cte ed to an exte xterr nal gr ound r od - Ans. A ns.

R os osii n-core so sold lde er - Ans.

What safety equipment should always be included in home-built equipment that is  powered from 120V AC power circui circuits? ts?

What is the characteristic appearance of a cold solder joint?

 A fuse or circuit brea reake kerr in se seri es with the AC hot conductor- Ans.

gr ainy or dull  A gra dull surfa surface ce - Ans. What is probably happening when an ohmmeter, connected across an unpowered circuit, initially indicates a low resistance and then shows increasing resistance with time?

What should be done to all external ground rods or earth connections? 

B ond them them toget together her with wi th heavy heavy wi wi r e or conductive str strap ap  Ans. 

Which is an important safety rule to remember when using a crank-up tower? to wer?

This type of tower must not be climbed unless unl ess re retr tracte acted d or or me mechani chanical cal safety locki ng devi devi ce cess have be been en i nstalled  Ans. What is considered to be a proper grounding method for a tower?

 Sep parat rate e eig ight ht-foo -foott lo long ng ground ground rod rodss for  Se each ea ch tower leg leg,, bonde bonded d to the towe towerr and eac ach h othe otherr - Ans. An s. Why should you avoid attaching att aching an antenna to a utility utility pole?

The antenna could contact high-voltage  po  p ower lines lines - Ans. Which is true when installing grounding conductors used for lightning protection?

 Sharp rp bend ndss must be avoide ided d - Ans.  Sha Which of the following is good practice when installing ground wires on a tower for lightning protection?

cirr cui cuitt co contains ntains a larg large e cap capacitor acitor T he ci  Ans.

What can happen if a lead-acid storage  battery is charged charged or discharg discharged ed too quickly?

E nsur nsure e that that connec connections tions are ar e shor shor t and di r ect - A ns.

Which precautions should be taken when measuring circuit resistance with an ohmmeter?

The battery could overheat, give off  flammable gas  flam gas,, or or exp explo lod de - Ans.

Purpose of a safety wire through a turnbuckle used to tension guy lines?  

15

 

Excel Review Center P r eve vent nt loose looseni ning ng of the gu guyy line li ne from fr om vibratii on - A ns.  vibrat What type of radiation are VHF and UHF radio signals?

Non-i onizing ra Non-io r adiatio iation n - Ans. Which frequency has the lowest value for Maximum Permissible Exposure limit?

 50 MH z - Ans. What is the maximum power level that an amateur radio station may use at VHF frequencies an RF exposure evaluation isbefore required?

ECT Coaching TH If the averaging time for exposure is 6 minutes, how much power density is  permitted if the signal is present present for 3 minutes and absent for 3 minutes rather than being present for the entire 6 minutes?

 2 tim time es as muc uch h - Ans. Which wire or wires in a four-conductor connection should be attached to fuses or circuit breakers in a device operated from a 240 VAC single phase source?

Only the tw two o wir wire es car car r yi ying ng voltage voltage  Ans.

What is the purpose of a power supply interlock?

ensurr e that that dang dange er ous voltages ar ar e T o ensu r em emove oved d i f the cabin cabine et is opened opened - Ans. A ns. What must you do when powering your house from an emergency generator?

sconnect nnect the i nco ncoming ming uti utilility ty pow powe er D i sco  fee  fe ed - Ans. What precaution should you take whenever you adjust or repair an antenna?

urn ur n off the transmitter disconnect ct T the feed fee d liline ne transmitte - Ans. A ns. r and disconne

 50 watt ttss PE P at at th the e ant nte enna - Ans. What factors affect the RF exposure of  people near an amateur station station antenna? A. Frequency and power level of the RF field B. Distance ffrom rom the antenn antennaa to a person C. Radiati Radiation on pattern of the antenna

D . A ll of of these these choices are co corr r ect - Ans. An s. Why do exposure limits vary with frequency?

According the National Electrical Code, what is the minimum wire size that may  be used safely for for wiring with with a 20 ampere circuit breaker?

 AWG num numb ber 12 - Ans. END Which size of fuse or circuit breaker would be appropriate to use with a circuit that uses AWG number 14 wiring?

15 amp er es - Ans. A ns. ampe

T he human human body body abso absorr bs more more RF R F ene enerr g y Which is a primary reason for not placing at som some e fr eq equenci uencies es than at at othe otherr s - Ans. A ns. a gasoline-fueled generator inside an Acceptable method to determine that your station complies with FCC RF exposure regulations? A. By calculation based on FCC FCC OET Bulletin 65 B. By cal calculation culation based on computer modeling C. By measurement measureme nt of field strength using calibrated equipment

of these these choices are co corr r ect - Ans. An s. D . A ll of What could happen if a person accidentally touched your antenna while you were transmitting?

The ey mi ght rece recei ve a pai nful R F bur urn n Th  Ans. Which action might amateur a mateur operators take to prevent exposure to RF radiati radiation on in excess of FCC-supplied limits?

occupied area? Danger of carbon monoxi monoxide de poisoning Ans. Which conditions will cause a Ground Fault Circuit Interrupter (GFCI) to disconnect the 120 or 240 Volt AC line  power to a device? device?

C ur urrr ent flow fl owii ng fr om one or mor mor e of the voltage-carrying wires directly to ground - Ans. Covered by the National Nat ional Electrical Code?

lectri tri cal safety safety i nsi nside de the ham shack E lec  Ans. What should be observed when climbing c limbing a tower using a safety belt or harness?

Confirm that the belt is rated for the weii gh we ghtt of the cli climb mbe er and that i t is i s within withi n i ts allo allowa wable ble se serr vice lilife fe - Ans. A ns.

elocate cate ante antennas nnas - Ans. Ans. R elo How can you make sure your station stays in compliance with RF safety regulations?

By re-evaluating the station whenever an i te tem m of equipme equipment nt is is chang change ed - Ans. A ns.

What should be done by any person  preparing to climb climb a tower that supports electrically powered devices?

 Make sure all circuits th tha at sup supp ply power to the towe towerr ar are e lock locked ed out and tagg tagged ed  Ans.

Why is duty cycle one of the factors used to determine safe RF radiation rad iation exposure levels?

Which is true of an emergency generator installation?

I t affec aff ects ts the aver aver age exposur exposure e of of pe peop ople le to r ad adii ation - Ans.

located d in a T he generator should be locate well-ventilated area - Ans.

What is the definition of duty cycle during the averaging time for RF exposure?

Which is a danger from lead-tin solder?

T he per per ce centage ntage of time ti me that a tr transmitter ansmitter is transm transmii tt tting ing - Ans.

L ead can can contam contami nate foo ood d if hands are not washed carefully after handling the  sold  so lde er - Ans.

How does RF radiation differ from ionizing radiation (radioactivity)?

Which is good practice for lightning  protection grounds?

R F r ad adii at atii on doe doess not hav have e suff suffii ci cie ent energ nergyy to cause g enetic dama damagg e - Ans. A ns.

They must be bonded together with all othe ot herr gr ound oundss - Ans. 16

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