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GBR 23
beacon receiver
owner’s
manual
and
reference
guide
GBR23Cover.p65 1 5/19/00, 3:39 PM
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© 2000 GARMIN Corporation GARMIN International, Inc. 1200 East 151st Street, Olathe, Kansas 66062, U.S.A. Tel. 913/397.8200 or 800/800.1020 Fax 913/397.8282 GARMIN (Europe) Ltd. Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9AQ, U.K. Tel. 44/1794.519944 Fax 44/1794.519222 GARMIN (Asia) Corporation No. 68, Jangshu 2nd Rd., Shijr, Taipei County, Taiwan Tel. 886/02.2642.8999 Fax 886/02.2642.9099 All rights reserved. Except as expressly provided herein, no part of this manual m
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Introduction GARMIN Corporation warrants this product to be free from defects in materials and manufacture for one year Limited Warranty from the date of purchase. GARMIN will, at its sole option, repair or replace any components that fail in normal use. Such repairs or replacement will be made at no charge to the customer for parts or labor. The customer is, however, responsible for any transportation costs. This warranty does not cover failures due to abuse, misuse, accident or unauthorized al
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Introduction All differential beacon receivers decode correction data determined at the beacon transmitter site via a GPS Cautions receiver(s). The GPS system is operated by the govern- ment of the United States which is solely responsible for their accuracy and maintenance. The DGPS beacon transmitters are operated by the U.S. Coast Guard (or similar government agency in other countries) which is responsible for their accuracy and maintenance. The Global Positioning System and the Differential
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Introduction Table of Contents Introduction Limited Warranty..............................................1 Cautions ..........................................................2 Table of Contents ............................................3 Product Registration ........................................4 Overview Capabilities & Package Contents......................5 Installation Mounting the GBR 23 .................................6-7 Connecting GBR 23 and GPS ....................8-10 Operation U
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Introduction Customer Service Product Registration Help us better support you by completing our on-line Product registration today! Have the serial number of your GBR Registration 23 handy and connect to our website (www.garmin.com). Look for the Product Registration link on the Home page. If you have previously registered a GARMIN product purchase using a mail-in registration card, we invite you to reregister using our NEW on-line system. Many services provided by our new product registration s
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Overview Capabilities The GBR 23 offers a host of powerful capabilities to Capabilities & enhance the performance and accuracy of your GPS Package Contents receiver: • Performance— The single channel receiver has The GBR 23 may be used with a high-sensitivity automatic and manual tuning variety of GARMIN GPS throughout the beacon broadcast band. receivers. The list below • Ease of Use— Once installed, operation is identifies most, but not all, controlled using your GARMIN GPS unit. The unit comp
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Installation Mounting the Receiver Please read through these instructions thoroughly before attempting installation. Make sure you completely understand Mounting the these instructions before you begin. When in doubt, seek GBR 23 professional assistance. The following additional items are needed or optional to complete the installation of your GBR 23: • Antenna mount— Since antenna mounting locations and methods vary, you will need to obtain an antenna mount to install the GBR 23. The receiver b
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Installation Three common sources of interference for DGPS units are: Mounting the ABOVE- OK Receiver Radar BELOW- OK 3' Radar VHF Radio I When routing the power/data cable, try to avoid: • Sharp edges which may cut the EMI cable • Routing the cable parallel to other power lines EMI (Electromagnetic Interference) from engine components • Excessively twisting, straining or bending the cable If a problem is found, try altering the location of the unit or wiring. Often moving the antenna a
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Installation Connecting the GBR 23 To Your GPS Unit The final step in installing the GBR 23 is to connect the receiver’s DATA IN, DATA OUT and GROUND lines Connecting the to your GPS unit. The GBR 23 is designed to transmit/ GBR 23 receive data at 4800 baud or BPS (bits per second), which is suitable for use with all differential-ready GARMIN GPS F receivers and select products made by other manufactur- You may also output corrected ers. NMEA data from a GARMIN GPS/ DGPS combination to a PC or F
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Installation Auto-Tuning Without external commands, the GBR 23 will automatically scan frequencies between 283.5-325.0 kHz Connecting @ 0.5kHz steps for 100 and 200 bps stations only. To use GBR and GPS 25 & 50 bps, you will need to manually tune the beacon via the GPS receiver or other source. For non-GARMIN receivers which do not supply a valid tuning interface (pg. 11-12) to the GBR 23, it is not necessary to connect to the DATA IN (BROWN) wire of the GBR 23. The GBR 23 should tune into a DGP
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Installation Connecting GBR and GPS Fuse (-) (+) 2-6A UNITS WITH 8-35 VDC 7 PIN PLUG GBR 23 Power / Data Cable (1) RED: POWER INPUT (1) RED: 8-35 VDC (2) BLACK: GROUND (2) BLACK: GROUND 4 3 (3) BLUE: DATA OUT (5) WHITE: REMOTE ON/OFF * 5 (4) BROWN: DATA IN (4) BROWN: DATA IN 2 (3) BLUE: DATA OUT (5) WHITE: NOT USED 6 (6) GREEN: NOT USED (6) GREEN: NOT USED 1 7 (7) YELLOW: ALARM (7) YELLOW : NOT USED Fuse (-) (+) 2-6A UNITS WITH 8-35 VDC 13 PIN PLUG GBR 23 Power /
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Operation Using the GBR 23 When using the GBR 23, tuning may be either done Using the automatically or controlled by the GPS unit. Your GBR 23 GARMIN GPS unit provides a Beacon Receiver Setup Page and, in some cases, Beacon Log Page for this purpose. The operating instructions provided below are generalized to cover several different GARMIN models and may not exactly match your display. For additional information on operating your GPS unit with the GBR 23, refer to the owner’s manual for your GP
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Operation 7. If the beacon signal is received, but no DGPS correction data is included, the message “No Using the Data” will appear at the bottom of the page. GBR 23 If no beacon signal is received, the “SNR” field will remain blank, “No Status” will appear at the bottom of the page. 8. To select another beacon transmitter, enter a new frequency and bit rate. 9. Some Garmin units have a list of the last five beacon frequencies used on the Beacon Log Page. As an alternative to reentering frequen
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GPS SIGNAL CORRECTION DATA DGPS (CORRECTION) SIGNAL Reference DGPS: How It Works Differential GPS (DGPS) is a technique used to DGPS: improve the accuracy of the Global Positioning System. How It Works DGPS reduces the effects of atmospheric variations and can improve position accuracy to better than 5 meters. GPS RECEIVER STATION AND DGPS TRANSMITTER SHIPBOARD GPS AND DGPS RECEIVERS After entering the beacon’s Figure 4: The DGPS System operating frequency, set the bit rate as indicated o
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Reference Satellites received by the shipboard GPS receiver, but not by the GPS receiver at the beacon transmitter site, will DGPS: not have corresponding corrections. When four or more How It Works satellites received by the shipboard GPS receiver have corresponding corrections, the result is a highly accurate position reading. The more satellites with corrections, the more accurate the position. The GBR 23 receives RTCM-SC-104 format signals from ground based DGPS Beacon Stations operating in
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Reference Sources of Error Using a DGPS Beacon Receiver with your existing Sources of GPS Receiver can provide substantial improvements in Error accuracy; however, there may be occasions when the best possible accuracy will not occur. Several factors can contribute to a degraded DGPS accuracy. Loss of DGPS Beacon Signal— Obviously, the lack of DGPS correction data will result in reduced accuracy. Accuracy will be the same as if no beacon receiver was being used. Several conditions can cause a l
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Reference Number of Satellites Visible— As previously stated, the number of satellites available can affect Sources of position accuracy. To apply the corrections provided for Error the satellites received at the beacon transmitter station, the same satellites (at least in part) must be received by your GPS receiver. And, certainly, if there aren’t enough satellites to determine a GPS position, there aren’t enough satellites to calculate a DGPS position. Atmospheric Conditions— Differences in th
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Reference Troubleshooting Possible Cause Problem Chart 1) “Check Wiring” Power switch/wiring faulty. displayed on GPS unit Fuse/breaker blown (if used). GBR 23 not wired properly with GPS unit. Check wiring. If the BROWN (Data In) wire is not used (Auto-tuning), this message may be displayed. If the receiver status screen displays the GPS is receiving differential corrects, no action is needed. 2) “No DGPS Position” Not enough data is available to displayed on GPS unit compute a DGPS position. P
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Reference Problem Possible Cause Troubleshooting Chart GBR 23 not wired properly with 6) GPS interface GPS unit. Check wiring. status screen displays “None” or “No Status” No power to GBR 23. See Troubleshooting problem 1. Possible damage to the with DGPS antenna. Baud rates do not match. Beacon transmitter out of range. Try a different station. Interference from ship’s 7) Beacon signal weak electrical system, thunderstorm or not received. activity, or another source is If the ‘No Differential G