Garmin DGPS 53 User manual

owner’s
manual
and
reference
guide
DGPS 53
integrated
GPS/DGPS receiver
DGPS53Cover.p65 8/29/00, 11:10 AM1

© 2000 GARMIN Corporation
GARMIN International, Inc.
1200 East 151st Street, Olathe, Kansas 0 2, U.S.A.
Tel. [phone] or 800/800.1020
Fax [phone]
GARMIN (Europe) Ltd.
Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9AQ, U.K.
Tel. [phone]
Fax [phone]
GARMIN (Asia) Corporation
No. 8, Jangshu 2nd Rd., Shijr, Taipei County, Taiwan
Tel. [phone]
Fax [phone]
All rights reserved. Except as expressly provided herein, no part of this manual may
be reproduced, copied, transmitted, disseminated, downloaded or stored in any
storage medium, for any purpose without prior written consent of GARMIN
Corporation. GARMIN Corporation hereby grants permission to download a single
copy of this manual onto a hard drive or other electronic storage medium to be
viewed for personal use, provided that such electronic or printed copy of this
manual contains the complete text of this copyright notice and provided further that
any unauthorized commercial distribution of this manual is strictly prohibited.
Information in this manual is subject to change without notice. GARMIN
Corporation reserves the right to change or improve its products and to make
changes in the content without obligation to notify any person or organization of
such changes. Visit the GARMIN website for current updates and supplemental
information concerning the use and operation of this and other GARMIN products.
Website address: www.garmin.com
GARMIN and DGPS 53 are registered trademarks of GARMIN Corporation and may
not be used without the express permission of GARMIN Corporation.
September 2000 Part Number 190-00194-00 Rev. A Printed in Taiwan
DGPS53Cover.p65 8/29/00, 11:10 AM2

1
Introduction
Limited Warranty
GARMIN Corporation warrants this product to be free
from defects in materials and workmanship for one year
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 alteration or repairs.
THE WARRANTIES AND REMEDIES CONTAINED
HEREIN ARE EXCLUSIVE AND IN LIEU OF ALL OTHER
WARRANTIES EXPRESS OR IMPLIED OR STATUTORY,
INCLUDING ANY LIABILITY ARISING UNDER ANY
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE, STATUTORY OR OTHERWISE.
THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS,
WHICH MAY VARY FROM STATE TO STATE.
IN NO EVENT SHALL GARMIN BE LIABLE FOR ANY
INCIDENTAL, SPECIAL, INDIRECT OR CONSEQUEN-
TIAL DAMAGES, WHETHER RESULTING FROM THE
USE, MISUSE, OR INABILITY TO USE THIS PRODUCT
OR FROM DEFECTS IN THE PRODUCT. SOME STATES
DO NOT ALLOW THE EXCLUSION OF INCIDENTAL OR
CONSEQUENTIAL DAMAGES, SO THE ABOVE
LIMITATIONS MAY NOT APPLY TO YOU.
To obtain warranty service, contact your GARMIN
dealer or call the GARMIN Customer Service department
(913-397-8200) for a returned merchandise tracking
number. The unit should be securely packaged with the
tracking number clearly marked on the outside of the
package and sent freight prepaid and insured to a GARMIN
warranty service station. A copy of the original sales receipt
is required as the proof of purchase for warranty repairs.
GARMIN retains the exclusive right to repair or replace the
unit or software or offer a full refund of the purchase price
at its sole discretion. SUCH REMEDY SHALL BE YOUR
SOLE AND EXCLUSIVE REMEDY FOR ANY BREACH OF
WARRANTY.
The GARMIN DGPS 53 has no
user-serviceable parts. Should
ou ever encounter a problem
with our receiver, please contact
our GARMIN dealer or the
GARMIN Customer Service
department (913-397-8200 or
800-800-1020) for repairs.
An attempt to open the case to
change or modif the unit in an
wa will void our warrant and
ma result in permanent damage
to the equipment.
I

2
Introduction
Cautions
All differential beacon receivers decode correction data
determined at the beacon transmitter site via a GPS
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 Global
Positioning System are under development and are subject
to changes which could affect accuracy and performance
of all GPS/DGPS equipment. Although a GPS/DGPS
system is a precision electronic NAVigation AID
(NAVAID), any NAVAID can be misused or misinterpreted,
and therefore become unsafe. Use the GPS/
DGPS system at your own risk. To reduce this risk,
carefully review and understand all aspects of this Owner’s
Manual and carefully compare indications from your
display to all available navigation sources including the
information from other NAVAIDs, visual sightings, charts,
etc. For safety, always resolve any discrepancies before
continuing navigation.
NOTE: This device complies with Part 15 of the FCC
rules. Operation of this device is subject to the following
conditions: (1) This device may not cause harmful
interference, and (2) this device must accept any
interference received, including interference that may
cause undesired operation.

3
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 DGPS 53................................ -7
Connecting DGPS 53....................................8-9
Operation
Using the DGPS 53 .......................................10
NMEA Sentences......................................11-18
One-Pulse-Per-Second Output.......................18
Reference
GPS: How It Works .......................................19
DGPS: How It Works ....................................20
Sources of Error .......................................21-22
Troubleshooting Chart ..................................23
DGPS 53 Specifications .................................24
Appendix A: Earth Datums.......................25-27
Index .............................................................28

4
Introduction
Product
Registration
Customer Service Product Registration
Help us better support you by completing our on-line
registration today! Have the serial number of your DGPS
53 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 system
are now being automated and reregistering your purchase
ensures you the best possible support from GARMIN.
Wh should ou register our
GARMIN GPS unit?
• Notification of Product Updates
• Notification of New Products
• Lost or Stolen unit tracking
H
The GARMIN DGPS 53 has no user-
serviceable par s. Should you ever encoun er
a problem wi h your uni , please con ac
your GARMIN dealer or GARMIN Cus omer
Service (913-397-8200 or 800-800-1020) for
repairs.
Repairs should only be made by an authorized
GARMIN service center. Unauthorized repairs or
modifications could void your warranty and authority to
operate this device under FCC Part 15 regulations. See
page 1 of this manual for further service details.
I
Serial Number
Use this area to record the serial number (8-digit
number located on the bottom of the unit) in case it is
lost, stolen, or needs service. Be sure to keep your original
sales receipt in a safe place or attach a photocopy inside
the manual.
Serial Number:
**

5
Capabilities
The DGPS 53 offers a host of powerful capabilities for
enhanced performance and accuracy:
• Performance— 12-channel GPS receiver tracks and
uses up to 12 satellites for fast, accurate positioning.
Single channel DGPS receiver has high-sensitivity
automatic and manual tuning throughout the
beacon broadcast band.
• Ease of Use— Once installed, unit will automati-
cally transmit navigation data.
• Convenience— May be remotely mounted in an
out-of-the-way location. Receiver status information
is displayed directly on the chartplotter or PC.
• Low Power Consumption— Draws approximately
170 milliamps during normal operation.
• ccuracy— 1-5 (2DRMS) meters (typical).
Package Contents
Your GARMIN DGPS 53 package includes:
• DGPS 53 unit
• 30’ Power/Data Cable
• Owner’s Manual & Reference Guide
• Beacon Reference Card
If any parts are missing or damaged, please
contact your G RMIN dealer immediately.
Capabilities &
Package Contents
Overview

6
Mounting the Receiver
Please read through these instructions thoroughl before
attempting installation. Make sure ou completel understand
these instructions before ou begin. When in doubt, seek
professional assistance.
The following additional items are needed or optional
to complete the installation of your DGPS 53:
• ntenna mount— Since antenna mounting
locations and methods vary, you will need to obtain
an antenna mount to install the DGPS 53. The
receiver base fits a standard 1-inch, 14 threads-per-
inch mount. Check with your GARMIN dealer or a
marine supply retailer for this item.
• On/Off switch (optional)— Power to the
receiver may be controlled by an on/off switch, such
as an accessory switch on the control console.
Check with your GARMIN dealer or a marine/
electric supply retailer for this item.
• G RMIN 60’ Power/Data Cable— for cable
installation lengths greater than 30’. Part number
010-10284-00
It is recommended that the system be temporarily
hooked up with the wiring and the unit placed at the
desired installation location. Then, check operation with
potential interfering equipment turned on and off. (For
example, other electronic equipment, fan motors, engine
ignition, alternators, generators, radars and VHF radio
transmissions can be sources of interference.)
Position the receiver so that the clearest possible view
of the sky and horizon in all directions is obtained. Avoid
mounting the antenna next to large areas of conductive
material (metal, aluminum, etc.) as this may cause poor
signal reception. The DGPS 53 is supplied with a 30 feet
power/data cable. When routing the wiring to the DGPS
53, avoid routing the cable near the vessel’s alternator or
ignition system components or parallel to other power
lines.
Installation
Mounting the
DGP 53
I
Note: As a general rule,
mount the receiver at least
three feet from all other
antennas and the vessel’s
electrical s stem components
(alternator/ignition s stem).

7
Installation
Mounting the
Receiver
If a problem is found, try altering the location of the
unit or wiring. Often moving the antenna a few feet away
from the source of interference will solve the problem.
When a suitable configuration is found, a permanent
installation should be made. Select the mounting location
according to your preferences. Keep in mind that from this
mounting location cables will be routed to the antenna and
to the GPS unit.
1. Once a suitable mounting location has been
determined and tested, secure the antenna mount at
the desired mounting location.
2. Make sure the DGPS 53 is aligned properl to avoid
thread damage. Thread the DGPS 53 onto the
antenna mount and hand tighten clockwise until
snug (Fig. 1). Do not overtighten.
3. Align the notches on the power/data cable and
DGPS 53 connector and push the connector in until
it seats. Turn the locking ring clockwise until the
power/data cable is firml locked into position.
4. Route the power/data cable from the DGPS 53 to the
GPS unit. Excess cable ma be shortened or coiled
together and secured in an inconspicuous location. If
additional cable is needed ou ma use GARMIN’s
optional 60’ cable (010-10284-00) or similar 24
AWG shielded wiring. The entire length of the
power/data cable should not exceed 150’ (45.7m).
Three common sources of interference for DGPS
units are:
Radar
ABOVE- OK
BELOW- OK
EMI
3'
VHF Radio Antenna
Radar
EMI (Electromagnetic Interference) from engine components
Power/Data
Cable &
Connectors
Antenna
Mount
When routing the power/data
cable, tr to avoid:
• Sharp edges which ma cut the
cable
• Routing the cable parallel to
other power lines
• Excessivel twisting, straining or
bending the cable
I
Figure 1: Mounting
the DGPS 3

8
Installation
Connecting the
DGP 53
Connecting the DGPS 3
The final step in installing the DGPS 53 is to connect
the receiver’s DATA IN, DATA OUT, REMOTE ON/OFF
and GROUND (Return) lines to your chartplotter or PC.
The DGPS 53 is designed to transmit/receive data at
4800-19200 baud (bits per second), which is suitable for
use with most devices and PCs.
For reliable communication, it is essential that the
DGPS 53 and the receiving device share the same ground.
This ground connection acts as the (current) Return line.
It is recommended to wire the unit to it’s own circuit to
avoid interference from other electronics.
1. You ma reference Figures 3 or 4 on the following
page for the wiring: Connect the BLUE (Data Out)
wire from the DGPS 53’s power/data cable to the
DATA INPUT line of the chartplotter or to pin 2 on
the DB9 (pin 3 on DB25).
2. Connect the BROWN (Data In) wire to the DATA
OUTPUT line of the chartplotter or pin 3 on the DB9
(pin 2 on DB25).
3. Connect the BLACK (-) wire to the GROUND wire of
the chartplotter or pin 5 on the DB9 (pin 7 on
DB25). If the BLACK wire is alread connected to
the same ground terminal as the GPS unit, no
additional connection is required (unless a separate
RETURN line is provided b the GPS unit).
4. Connect the RED (+) wire from the power/data
cable to a 8-35 VDC power source.
5. If a remote power switch is being installed,
reference Figure 5 for wiring the switch. This will
allow the DGPS 53 to remain connected to a power
source, but manuall powered on and off.
Otherwise, if the receiver is being wired to a circuit
which is alread switched, (with the chartplotter for
example) connect the WHITE wire to the same place
as the BLACK wire. When the BLACK and WHITE
wires are combined, the DGPS 53 will turn on/off
when power is applied/removed to the RED (+) and
BLACK (-) wires.
6. If one-pulse-per-second (PPS) output is being used,
connect the YELLOW (+) and BLACK (-) wires to
our desired device inputs. See page 18 for more
information on PPS.
I
If the DGPS 53 is being connected to
a PC, a DB9 or DB25 serial
connector (normall female) will be
needed. Check with a PC or
electronics supplier for this item.
Some non-GARMIN devices ma
have a separate data line labeled
“RETURN”, “DATA GROUND” or
“DATA -”. If one of these lines exist,
connect the BLACK wire from the
power/data cable to it.
1 4
6789
2
3
5
14
7
25
13 1
2
3
F
DB9 Female Serial Connector
DB25 Female Serial Connector