Sorry, Garmin has discontinued this product

Be sure to read the Garmin GPS-25 Frequently Asked Questions below.

Read about recommended power supply designs for the GPS-25.

• Garmin GPS-25 (12 channel parallel sensor) engine (1.83" x 2.75" x .45")
• Power/data cable with connector shell and pins
  (The connector is a mfg subminiature PCB edge connector with cable attached)
  A $12 value.
• Documentation

  GPS-25 Technical Specification (pdf, 115K, 35 pages)
  

Please note: This is not an enclosed/sealed unit. It is assumed that the purchasers will be installing the unit in another enclosure for normal and experimental operations. These units will be useful with current APRS software and the TAC-2 (Totally Accurate Clock) kit designed by Tom Clark, W3IWI.

As well as the MIC-E kit for APRS tracking.

General Information

All Garmin engines come complete with DGPS input capability (see note below), PPS timing output and lithium 3V battery on board

The Garmin GPS-25 will simultaneously track up to twelve satellites providing fast time-to-first-fix, one second navigation updates and low power consumption.

Footprint (1.83" x 2.75" x .45")

Time to first fix
	reacquisition	< 2 sec
	warm	15 sec
	cold	45 sec
	sky search	5 min
	update rate	1 sec continuous
Dynamics
	velocity	999 knots
	acceleration	3 g
	jerk	20 m/s^3
Datums
	102 predefined, 1 user defined
Electrical
	input voltage	5.0V DC +- 5% regulated (a suitable regulator should be used)
	power consumption	220mA typical, 180mA reset, 350mA max.
	backup	on board 3V lithium (10 year lifetime)
	sensitivity	-165 dBW
Connector
	antenna	50 ohm MCX female connector for active (5V DC @ 15ma) or passive antenna
	power/data	single row, right angle 12 pin male
Physical
	configuration	1 integrated board engine
	size	1.83"W X 2.75"L X 0.45"H
	weight	1.1 oz
	op temp	-30 deg C - +85 deg C (remove Li battery for extended usage above 85 deg C)
	storage temp	-40 deg C - +90 deg C
Interface
	compatibility	2 RS-232 serial ports
	data rate	User selectable baud rate 1200/2400/4800/9600
	format	NMEA 0183 v.2.0, ASCII
	inputs	Initial position, date and time (not required), 2D/3D & earth datum command, RTCM-104 v.2.0 differential
	outputs	Position, velocity & time, receiver and satellite stautus, geometry and error estimates
	timing output	Timing output with +- 1 microsecond accuracy

Ordering Information

Sorry, Garmin GPS25LVS is no longer available

Frequently Asked Questions

• The GPS-25 can accept DGPS signals.

• Antenna options (which can be purchased directly from Garmin if required) include:
  • mag mount
  • flange mount (bolt to a car)
  • trunk clip
  • suction cup mounted

• The unit has true time clocks, PPS timing, and nonvolatile memory on board.

• The interface is NMEA 0183 (TTL levels) and RS232 (+ and - 15 volts)

• The unit can be powered by AA batteries. Batteries or external supplies will require a suitable power regulator.

• The unit only gives NMEA sentences as output, no extraction of RTCM-104 data.

• There's no problem with the antenna being close to the boards. All sensitive components are shielded.

• The unit has a LNAs and you can use passive antennas. You need to keep the antenna runs short however.

• The antenna is attached with a MCX (also know as OCX) connector, which is a friction lock connector.

• There's a header for connecting the data cables. A connector and cable will be included in the kit. The connector is a subminiature PCB edge connector. This is not the same connector as used with many hand-held units.

• You cannot adjust the intervals that the boards outputs data. However, you can adjust their baud rate.

• The boards do adjust for leap seconds (via the satellites).

• For DGPS, since these are just the boards, you can't use the Garmin DGPS receivers. The Garmin units get tuning instructions from the GPS keyboard (which are not on the boards). To receive DGPS signals, you'll need a tunable beacon receiver. Correction signals are sent in through the data in cable (just like the handhelds).

• Will the documentation include full description of the proprietary protocol?
  The data on their "proprietary" command protocol is included. Here "proprietary" means a "non-standard" NMEA command. They start with $PG instead of $GP...

• Will there be a 1 Hz output?
  Yes, there is a 1pps signal at no extra charge!

• Does Garmin have a web page?
  www.garmin.com.

• It appears the GPS-25 does NOT have a built-in display but one has to use an external computer with unspecified software. Also the external computer is required to provide tuning instructions. Is this correct?
  This is just the GPS engine that produces NMEA outputs. No display, no user functions...