Trimble Gps in St

COPYRIGHT NOTICE  © 1995 TRIMBLE Reproduction of this publication or any portion thereof by any means without the express written permission of TRIMBLE is prohibited. For further information information contact, Manager, Technical Publications, TRIMBLE, Avionics Division, 2105 Donley Drive, Drive, Austin, Texas 78758. Telephone (512) 432-0400.



Trimble 2000 Approach GPS Receiver Insert latest change pages and destroy superceded pages.

LIST OF EFFECTIVE PAGES Dates of Original and Change pages are: Revisi Revision on ...... ......... ..... Revisi Revision on ...... ......... ..... Revisi Revision on ...... ......... ..... Revisi Revision on ...... ......... ..... Revisi Revision on ...... ......... .....

A ...... ......... ... Januar January y 6, 1995 B ...... ......... ... Februa February ry 23, 199 1995 5 C ...... ........ .. July July 28, 28, 199 1995 5 D ...... ........ .. Novemb November er 4, 4, 1996 1996 E ...... ......... ... Januar January y 13, 1997

Page Description

Page no.

Front Cover

-

January 13, 1997

List of Effective Pages

A

January 13, 1997

Record of Revisions

B

January 6, 1995

Table of Contents (Main)

i - iii

January 6, 1995

Table of Contents (Section I)

1-i

January 6, 1995

Section I - General Information

1-1 1-2 1-3 - 1-5 1-6 1-7 1-8

Table of Contents (Section II)

2-i

Section II - Installation

2-1 2-2 2-3 - 2-5 2-7 2-9 2-11 - 2-14 2-15 2-16 - 2-25

Table of Contents (Section III)

3-i

Section III - Checkout

3-1 - 3-2 3-3 3-4 3-6 - 3-8

November 4, 1996 February 23, 1995 November 4, 1996 January 6, 1995

Appendix A - RTCA/DO 160-C Environmental Qualification Forms

A -1 - A -4

January 6, 1995

Appendix B - Serial Interface Specification

B - 1 - B - 18

January 6, 1995

Appendix C - Supplemental Flight Certificate and Flight Manual Supplement Example

C-1, C-2

January 6, 1995

Revision E January 13, 1996

Date

January 6, 1995 February 23, 1995 January 6, 1995 February 23, 1995 July 28, 1995 January 6, 1995 January 6, 1995 January 6, 1995 February 23, 1995 January 6, 1995 January 13, 1997 July 28, 1995 January 6, 1995 January 13, 1997 January 6, 1995 January 6, 1995

Page A



Trimble 2000 Approach GPS Receiver

RECORD OF REVISIONS Assigned To (Job Title)

Rev No.

Revision C July 28, 1995

Revision Date

Location

Insertion Date

By

Rev No.

Revision Date

Insertion Date

By

Page B



Trimble 2000 Approach GPS Receiver

TABLE OF CONTENTS SECTION I - General Information 1.1

INTRODUCTION ---------------------------------------------------------------------------------- 1-1

1.2

DESCRIPTION OF EQUIPMENT ------------------------------------------------------------- 1-2 1.2.1 1.2.2

1.3

TECHNICAL CHARACTERISTICS ----------------------------------------------------------- 1-4 1.3.1 1.3.2 1.3.3 1.3.4

1.4

Receiver/Display Units (P/N 81438-XX) ------------------------------------------------------ 1-4 GPS Antenna (P/N 16248-20) ----------------------------------------------------------------- 1-5 GPS Antenna (P/N 16248-11) (alternate) ---------------------------------------------------- 1-5 GPS Antenna (P/N 81194) (alternate) -------------------------------------------------------- 1-6

PARTS AND EQUIPMENT SUPPLIED ------------------------------------------------------ 1-7 1.4.1 1.4.2

1.5

Receiver/Display Unit ----------------------------------------------------------------------------- 1-2 GPS Antenna ---------------------------------------------------------------------------------------- 1-3

Trimble 2000 Approach GPS Receiver ------------------------------------------------------- 1-7 Installation Kit --------------------------------------------------------------------------------------- 1-7

ACCESSORIES NOT SUPPLIED ------------------------------------------------------------- 1-8 1.5.1 1.5.2

Installation -------------------------------------------------------------------------------------------- 1-8 GPS Cable Requirements ----------------------------------------------------------------------- 1-8

SECTION II - Installation 2.1

GENERAL------------------------------------------------------------------------------------------- 2-1

2.2

UNPACKING AND INSPECTING EQUIPMENT------------------------------------------- 2-1 2.2.1 2.2.2

2.3

Physical Inspection -------------------------------------------------------------------------------- 2-1 Electrical Inspection ------------------------------------------------------------------------------- 2-1

EQUIPMENT INSTALLATION ----------------------------------------------------------------- 2-1 2.3.1 2.3.2 2.3.3 2.3.4 2.3.5

Cooling Considerations --------------------------------------------------------------------------- 2-1 Harness and Cable Fabrication ---------------------------------------------------------------- 2-1 GPS Antenna Installation ------------------------------------------------------------------------ 2-2 Receiver/Display Unit Installation -------------------------------------------------------------- 2-3 Outside Air Temperature Probe (OAT) "K" Factor ----------------------------------------- 2-4

NEXT

Revision A January 6, 1995

Page i

Trimble 2000 Approach GPS Receiver



SECTION III - Checkout 3.1

GENERAL------------------------------------------------------------------------------------------- 3-1

3.2

SYSTEM CHECKOUT --------------------------------------------------------------------------- 3-1 3.2.1 3.2.2 3.2.3 3.2.4

3.3

Preliminary test ------------------------------------------------------------------------------------- 3-1 Serial Port Configuration ------------------------------------------------------------------------- 3-1 GPS Receiver Tests ------------------------------------------------------------------------------- 3-2 Analog Interface Check --------------------------------------------------------------------------- 3-4

FINAL ------------------------------------------------------------------------------------------------ 3-5 3.3.1 3.3.2

Configuration Record Sheet --------------------------------------------------------------------- 3-5 Flight Manual Supplement ----------------------------------------------------------------------- 3-5

ILLUSTRATIONS 2-1 2-2 2-3 2-4 2-5 2-6 2-7 2-8 2-9

Trimble 2000 Approach Pin-out ---------------------------------------------------------------- 2-4 GPS Antenna (P/N 16248-20) Installation Drawing --------------------------------------- 2-5 ARINC 743 GPS Antenna (P/N 16248-11) Installation Drawing (alternate) --------- 2-7 ARINC 743 Hi Speed GPS Antenna (P/N 81194) Installation Drawing (alternate) 2-9 Trimble 2000 Approach Installation Drawing ---------------------------------------------- 2-11 Mounting Tray Assembly Drawing ----------------------------------------------------------- 2-13 Typical System Interconnection -------------------------------------------------------------- 2-15 CDI/HSI Interconnection ------------------------------------------------------------------------ 2-17 Serial Port Interconnection --------------------------------------------------------------------- 2-19 NEXT

Page ii

Revision A January 6, 1995



Trimble 2000 Approach GPS Receiver

APPENDIX A - RTCA/DO-160C Environmental Qualification Forms A.1

RECEIVER/DISPLAY UNIT -------------------------------------------------------------------- A-1

A.2

GPS ANTENNA ----------------------------------------------------------------------------------- A-2

APPENDIX B - Serial Interface Specification B.1

INTRODUCTION ---------------------------------------------------------------------------------- B-1

B.2

BASIC COMMUNICATION PROTOCOL DESCRIPTIONS ----------------------------- B-1 B.2.1 B.2.2 B.2.3

RS-422 ----------------------------------------------------------------------------------------------- B-1 RS-232 ----------------------------------------------------------------------------------------------- B-1 RS-423 ----------------------------------------------------------------------------------------------- B-1

B.3

CONNECTOR PIN ASSIGNMENTS --------------------------------------------------------- B-2

B.4

SOFTWARE CONFIGURATION OF SERIAL PORTS ----------------------------------- B-3

B.5

RECEIVE PORTS --------------------------------------------------------------------------------- B-3 B.5.1 B.5.2 B.5.3 B.5.4

B.6

Configuration --------------------------------------------------------------------------------------Encoder Data Format ---------------------------------------------------------------------------RMI Data Format ---------------------------------------------------------------------------------Air Data Computer Format ----------------------------------------------------------------------

B-3 B-3 B-4 B-5

TRANSMIT PORTS ------------------------------------------------------------------------------ B-7 B.6.1 B.6.2 B.6.3 B.6.4 B.6.5

Configuration --------------------------------------------------------------------------------------- B-7 R0 and R1 Data Formats ------------------------------------------------------------------------ B-7 K0 and K1 Data Formats ----------------------------------------------------------------------- B-10 X0 and X1 Formats ------------------------------------------------------------------------------ B-13 Data Output Format Example ----------------------------------------------------------------- B-17

APPENDIX C - STCs and Flight Manual Supplements

Revision A January 6, 1995

Page iii



Trimble 2000 Approach GPS Receiver

TABLE OF CONTENTS SECTION I - General Information 1.1

INTRODUCTION ---------------------------------------------------------------------------------- 1-1

1.2

DESCRIPTION OF EQUIPMENT ------------------------------------------------------------- 1-2 1.2.1 1.2.2

1.3

TECHNICAL CHARACTERISTICS ----------------------------------------------------------- 1-4 1.3.1 1.3.2 1.3.3 1.3.4

1.4

Trimble 2000 Approach GPS Receiver ------------------------------------------------------- 1-7 Installation Kit --------------------------------------------------------------------------------------- 1-7

ACCESSORIES NOT SUPPLIED ------------------------------------------------------------- 1-8 1.5.1 1.5.2

Revision A January 6, 1995

Receiver/Display Units (P/N 81438-XX) ------------------------------------------------------ 1-4 GPS Antenna (P/N 16248-20) ----------------------------------------------------------------- 1-5 GPS Antenna (P/N 16248-11) (alternate) ---------------------------------------------------- 1-5 GPS Antenna (P/N 81194) (alternate) -------------------------------------------------------- 1-6

PARTS AND EQUIPMENT SUPPLIED ------------------------------------------------------ 1-7 1.4.1 1.4.2

1.5

Receiver/Display Unit ----------------------------------------------------------------------------- 1-2 GPS Antenna ---------------------------------------------------------------------------------------- 1-3

Installation -------------------------------------------------------------------------------------------- 1-8 GPS Cable Requirements ----------------------------------------------------------------------- 1-8

Page 1-i



Trimble 2000 Approach GPS Receiver

SECTION I - General Information 1.1

INTRODUCTION

This manual provides information about the electrical, mechanical, and physical characteristics of the Trimble 2000 Approach GPS Receiver (P/N 81438-XX) (see Table 1-1 for appropriate dash number). The first section serves as an introduction. It describes the technical specifications of the panel-mounted Receiver/Display unit, and the externally mounted GPS antenna. The following sections describe the installation and checkout procedures. Proper techniques must be followed to ensure correct operation.

Unit Part No.

8143800

8143801

8143810

8143811

Description

Ship Kit Part No. Install Kit Part No.

Receiver with black bezel & standard GPS antenna P/N 1624820

8146300

8144600

Receiver with black bezel & optional ARINC GPS antenna P/N 1624811

8146301

8144601

Receiver with black bezel & optional ARINC 743 Hi Speed GPS antenna P/N 81194

8146302

8144602

Receiver with gray bezel & standard GPS antenna P/N 1624820

8146303

8144600

Receiver with gray bezel & optional ARINC GPS antenna P/N 1624811

8146304

8144601

Receiver with gray bezel & optional ARINC 743 Hi Speed GPS antenna P/N 81194

8146305

8144602

Receiver with NVG black bezel & standard GPS antenna P/N 1624820

8146306

8144600

Receiver with NVG black bezel & optional ARINC GPS antenna P/N 1624811

8146307

8144601

Receiver with NVG black bezel & optional ARINC 743 Hi Speed GPS antenna P/N 81194

8146308

8144602

Receiver with NVG gray bezel & standard GPS antenna P/N 1624820

8146309

8144600

Receiver with NVG gray bezel & optional ARINC GPS antenna P/N 1624811

8146310

8144601

Receiver with NVG gray bezel & optional ARINC 743 Hi Speed GPS antenna P/N 81194

8146311

8144602

Table 1-1 Unit & Antenna Matrix

Revision A January 6, 1995

Page 1-1

Trimble 2000 Approach GPS Receiver

1.2



DESCRIPTION OF EQUIPMENT

The Trimble 2000 Approach Receiver provides long-range GPS navigation via a panel-mounted unit. Each system comprises receivers and antennas to perform specified functions. The Jeppesen database cards provide up-to-date information about airports and other navigation aids around the world. The Trimble 2000 Approach GPS System contains one panel-mounted Receiver/Display Unit (RDU) containing a GPS Receiver (9-channel), one GPS Antenna/Preamp, and applicable installation hardware all contained within P/N 81446-XX (see Table 1-1 for appropriate dash number). The Jeppesen database cards are available separately within P/N 81461-00 for North American information, P/N 81461-01 for International information, or P/N 81461-02 for Worldwide information. The first card is supplied by Trimble.

1.2.1

Receiver/Display Unit 

The Receiver/Display Unit (RDU) is the main component of the Trimble 2000 Approach navigation systems. The RDU consists of the GPS Receiver, the User Interface, and the System Interface. 1.2.1.1 GPS Receiver  The GPS Receiver interprets the satellite transmissions to determine the current position. This information is communicated to the pilot via the User Interface and to the connected equipment via the System Interface. 1.2.1.2 User Interface  The User Interface is accomplished by an LED Display, seven annunciator lights, nine illuminated push-button keys, two concentric selector knobs, a power switch, and a NavData card slot. A.

LED Display The Light Emitting Diode (LED) Display is a two-line, high intensity display with 20 characters per line. System information is shown on the display.

B.

Annunciator Lights The internal annunciator lights alert the pilot of warning and advisory messages. The annunciator lights are the Message (MSG), Hold (HLD), Parallel Track (PTK), Approach (APR), Waypoint Alert (WPT), Global Positioning System (GPS) and Random Autonomous Integrity Monitoring (RAIM).

C.

Push-Button Keys Nine illuminated push-button keys are used for mode selection and data entry. The keys are described as follows: Access Navigation Mode. Displays enroute navigation information.

Access Waypoint Mode. Allows pilot to view or select airports, SIDs, STARs, Approaches, VORs, NDBs, Intersections, and User-defined locations as waypoints in a flight plan or as a destination. Also allows pilot to create, edit, or delete User-defined waypoints. Access Flight Plan Mode. Allows pilot to create, use, edit, reverse, and delete flight plans.

Access Calculator Mode. calculations.

Page 1-2

Allows pilot to perform many common E6B computer

Revision B February 23, 1995



Trimble 2000 Approach GPS Receiver

Access Auxiliary Mode. Provides information about system status, sensor status, system setup and installation procedures. Also contains a programmable checklist function. Shows twenty nearest airports, VORs, NDBs, and Intersections.

Allows pilot to fly directTo the indicated location or activate the indicated flight plan.

Enters information into memory and used to begin and end data entry.

Allows the pilot to view system messages.

D.

Selector Knobs Two concentric selector knobs are used to select displays within modes and for data entry.

E.

Power Switch A push-pull power switch turns the RDU on and off.

F.

NavData Card Slot The NavData card slot accepts the Jeppesen NavData card which provides the pilot information on Airports, SIDs, STARs, Approaches, VORs, NDBs, and Intersections. Either a North American or International database may be used. The slot also accepts the Trimble NavPak Memory Card used by the Trimble NavPak flight planning system.

1.2.1.3 System Interface  The Trimble 2000 Approach communicates with connected equipment by the CDI outputs, Annunciators, and the Serial Inputs/Outputs. A.

CDI Outputs The RDU provides standard Course Deviation Indicator (CDI) output signals suitable for use by most CDIs.

B.

Annunciator Outputs The external annunciator lights alert the pilot of warning and advisory messages. The annunciator lights are Message (MSG), Hold (HLD), Waypoint Alert (WPT) and Approach (APR).

C.

Serial Inputs/Outputs The RDU provides two serial input ports and two serial output ports for general use. Data formats may be selected by the pilot.

1.2.2

GPS Antenna 

The GPS Antenna (P/N 16248-20) receives and amplifies GPS Signals. The GPS Antenna unit is an omnidirectional flat microstrip antenna with an integral preamplifier and is rated to 600 knots IAS. Two alternate antennas (P/Ns 1624811 & 81194) can be used with the Trimble 2000 Approach.

Revision A January 6, 1995

Page 1-3



Trimble 2000 Approach GPS Receiver

1.3

TECHNICAL CHARACTERISTICS 1.3.1

Receiver/Display Units (P/N 81438-XX) 

ENVIRONMENTAL COMPLIANCE

See Appendix A

TSO COMPLIANCE

C129 (A1)

BZT COMPLIANCE

Pending

PHYSICAL DIMENSIONS Height Width Depth

2.0 in (5.08 cm) 6.25 in (15.87 cm) 9.70 in (24.64 cm)

WEIGHT

3.0 lbs (1.36 kg)

TEMPERATURE Navigation Unit Database Card

-20°to +55°C 0°to +55°C

ALTITUDE

-1000 ft to +50,000 ft (cabin pressure)*

MAXIMUM TRACK VELOCITY

800 knots*

MOUNTING

Panel mounted with Trimble supplied rack

POWER REQUIREMENTS

1.0 A @ 14 Vdc (all units) 0.5 A @ 28 Vdc (all units)

SIGNAL INPUTS Serial Data Input Port 1 Serial Data Input Port 2

EIA RS-422, RS-423, RS-232 compatible EIA RS-232, RS-423, TTL compatible

SIGNAL OUTPUTS CDI NAV Flag out of view NAV Flag in view NAV Superflag Valid (28 Vdc installations) NAV Superflag Valid (14 Vdc installations) NAV Superflag Invalid (Both) TO/FROM Flag (To indication) TO/FROM Flag (From indication) External Annunciators

Annunciator Limits Serial Data Output Port 1 Serial Data Output Port 2 *

Page 1-4

±150 mV full scale +Right 350 to 900 mV, up to 5, 1 k Ω parallel loads < 3.5 mV > 18 V > 10 V < 3.5 V +40 to +160 mV -40 to -160 mV, up to 5, 200 Ω parallel loads Message (MSG) Waypoint Alert (WPT) Hold (HLD) Approach (APR) Maximum Voltage: 30 Vdc Maximum Sink Current: 200 mA EIA RS-422 EIA RS-423, RS-232 compatible

Complies with USA export requirements

Revision A January 6, 1995



Trimble 2000 Approach GPS Receiver

1.3.1.1 GPS Receiver  TYPE

L1 Frequency (1575 MHz), C/A Code, Nine Channel

ACQUISITION TIME

1.5 to 3.5 minutes

POSITION UPDATE RATE

4 per second

DYNAMICS

800 knots, 6g (tracking)

ACCURACY Position Velocity Altitude Time

15 meters RMS** 0.1 knots steady state** 35 meters RMS** (MSL) UTC to the nearest microsecond ** Selective Availability not implemented

1.3.2

GPS Antenna (P/N 16248-20) 

TSO COMPLIANCE

C129 *

ENVIRONMENTAL COMPLIANCE

See Appendix A

PHYSICAL DIMENSIONS Height Width Length

0.80 in (2.0 cm) 3.75 in (9.53 cm) 4.00 in (10.16 cm)

WEIGHT

0.44 lb (0.2 kg)

TEMPERATURE

-55°C to +70°C

ALTITUDE RANGE

-1000 ft to +55,000 ft

MOUNTING

External

POWER REQUIREMENTS

+5 Vdc @ 80 mA from NPU

SPEED RATING

600 knots IAS

CONNECTOR

SMA

* Installations utilizing this antenna are limited to aircraft not equipped with Satellite Communications equipment.

Revision A January 6, 1995

Page 1-5



Trimble 2000 Approach GPS Receiver

1.3.3

GPS Antenna (P/N 16248-11) (alternate) 

TSO COMPLIANCE

C129 *

ENVIRONMENTAL COMPLIANCE

See Appendix A

PHYSICAL DIMENSIONS Height Width Length

0.80 in (2.0 cm) 3.75 in (9.53 cm) 4.00 in (10.16 cm)

WEIGHT

0.5 lb (0.23 kg)

TEMPERATURE

-55°C to +70°C

ALTITUDE RANGE

-1000 ft to +55,000 ft

MOUNTING

External

POWER REQUIREMENTS

+5 Vdc @ 80 mA from NPU

SPEED RATING

600 knots IAS

CONNECTOR

TNC

* Installations utilizing this antenna are limited to aircraft not equipped with Satellite Communications equipment.

1.3.4

GPS Antenna (P/N 81194) (alternate) 

TSO COMPLIANCE

C115a, C129 *

ENVIRONMENTAL COMPLIANCE

See Appendix A

PHYSICAL DIMENSIONS Height Width Length

0.60 in (1.52 cm) 3.00 in (7.62 cm) 4.70 in (11.94 cm)

WEIGHT

0.375 lb (0.17 kg)

TEMPERATURE

-55°C to +85°C

ALTITUDE RANGE

-100 ft to +55,000 ft

MOUNTING

External

POWER REQUIREMENTS

+5 Vdc @ 40 mA max from NPU

SPEED RATING

1300 knots IAS

CONNECTOR

TNC

Page 1-6

Revision B February 23, 1995

 1.4

Trimble 2000 Approach GPS Receiver

PARTS AND EQUIPMENT SUPPLIED 1.4.1

Trimble 2000 Approach GPS Receiver 

The Trimble 2000 Approach GPS Receiver is included in the Trimble 2000 Approach Shipping Kit P/N 81463-XX (see Table 1-1 for appropriate dash number) with the hardware required for proper installation. Listed below are the contents of the Trimble 2000 Approach GPS Shipping Kit. TPN

QTY

81438-XX 81446-XX

1.4.2

1 1

DESCRIPTION GPS Receiver/Display Unit Trimble 2000 Approach Installation Kit

Installation Kit 

The Installation Kit, supplied in the shipping kit within P/N 81446-XX (see Table 1-1 for appropriate dash number), contains the decals, labels, NavData subscription form, manuals, appropriate connectors, and installation hardware. Where available, the vendor and vendor part number are included. This is provided as a convenience to the installation agency and Trimble reserves the right to substitute equivalent parts without prior notice. The contents are listed below: P/N

DESCRIPTION

16248-20 * 16248-11 * 81194 80116 14719-00 14420-00 16581 16940 81449 81450 16165 81460 10257 10560 11055 80832 14423 14424 14426 16167 16168 16169 16707 80399 16737

GPS Antenna/Preamp GPS Antenna, ARINC GPS Antenna, ARINC 743 Hi Speed Antenna Mounting Gasket Antenna Cable, SMA Mounting Tray Cockpit Label Set NavData Information and Subscription Trimble 2000 Approach Pilot Guide Trimble 2000 Approach Installation Manual 24-pin Connector Connector, Adapter, TNC Plug-SMA Jack Screw 4-40 x 1/4 PL PH Nylon Duro Strip, 5 in Screw 4-40 x 1/2 PL FH Tie Wrap Tefzel 4" Rear Panel Cage Rear Panel Guard Airway Tube Tray Screw m2.5 x 10mm ss Retaining Ring Tie Wrap Cable GPS Antenna Template GPS Antenna Template Foam Rubber Tube

QTY 8144600 01 02 1 1 1 1 1 1 1 1 1 6 1 1 1 1 1 1 3 1 1 1 1

1 1 1 1 1 1 1 1 1 1 6 1 1 1 1 1 1 3 1 1 1 1

1 1 1 1 1 1 1 1 1 6 1 1 1 1 1 1 3 1 1 1 1

VENDOR & P/N

Amp 90 50/57-20240 -

* Installations utilizing this antenna are limited to aircraft not equipped with Satellite Communications equipment.

Revision C July 28, 1995

Page 1-7



Trimble 2000 Approach GPS Receiver

1.5

ACCESSORIES NOT SUPPLIED 1.5.1

Installation 

Circuit Breaker (required)

3 A for 14 V installations (P & B W58-XC4C12A-3) 2 A for 28 V installations (P & B W58-XC4C12A-2)

Analog CDI or HSI

Dedicated or switched through relay

External Annunciators (4)

Message (MSG) * -- Amber Waypoint Alert (WPT) * -- Green or Amber HLD (HLD) * -- Green or White Approach (APR) * -- Green or White * Required Annunciator

1.5.2

GPS Cable Requirements 

The GPS Cable (RG-316) provided in the shipping kit is 20 feet long. An alternate, prefabricated 50 foot cable is available from Trimble (P/N 14719-01 which includes adapter P/N 14719-04). 1.5.2.1 GPS Cable Lengths Greater Than 50 Feet  For GPS antenna cable lengths longer than 50 feet, the GPS antenna cable is to be supplied and fabricated by the installation agency to meet the following requirements: Insertion Loss DC Resistance

< 10 dB @ 1.575 GHz