The Garmin GPS 18x PC is a high-sensitivity, waterproof GPS sensor designed for use with personal computers and other compatible devices. It features a built-in patch antenna, NMEA 0183 and Garmin serial data output protocols, and provides reliable position, velocity, and time data for navigation, mapping, and timing applications. Below are key sections for overview, installation, configuration, operation, specifications, and troubleshooting.
Key components: GPS 18x sensor unit, DB-9 serial cable, mounting bracket, power/data cable, documentation.
| Feature | Description |
|---|---|
| GPS Receiver | High-sensitivity, 12-channel WAAS-enabled |
| Output Protocols | NMEA 0183 v3.01, Garmin serial (binary) |
| Interface | RS-232 serial (DB-9 connector) |
| Power Supply | 6–40 VDC, 45 mA typical |
| Antenna | Built-in patch antenna with MCX connector for external antenna |
| Waterproof Rating | IPX7 (submersible 1 meter for 30 minutes) |
| Operating Temp | -15° to 70° C (5° to 158° F) |
| LED Indicator | Red/Green status LED |
| Mounting | Includes bracket for permanent installation |
| Dimensions | 2.3" x 2.3" x 0.9" (58 x 58 x 23 mm) |
Unpack and verify all items are present.
NOTE: Contact your dealer if any items are missing or damaged.
Install the GPS 18x in a location with clear view of sky.
WARNING! Ensure power is off during installation. Use proper wire gauges and secure connections.
Configure PC software to communicate with GPS 18x.
Tip: Check Device Manager in Windows to confirm COM port number.
Adjust settings using terminal software or Garmin configuration utilities.
LED Indicators: Red = power on, no fix; Green blinking = tracking satellites; Green solid = valid fix.
Output Rate: Default 1 Hz. Can be increased via proprietary commands.
Data Sentences: Default NMEA output includes GGA, GSA, GSV, RMC. Configure using PMTK commands.
Baud Rate: Change via PMTK251 command (e.g., 4800, 9600, 19200, 38400).
Factory Reset: Send PMTK314,-1 to restore defaults.
Use with mapping, navigation, or data logging software.
Common Software: Google Earth, GPSUtility, Virtual GPS, marine navigation programs.
Standard NMEA sentences provided.
| Sentence | Description |
|---|---|
| $GPGGA | Global positioning system fix data |
| $GPGSA | GPS DOP and active satellites |
| $GPGSV | GPS satellites in view |
| $GPRMC | Recommended minimum specific GPS/Transit data |
| $GPVTG | Course over ground and ground speed |
Example: $GPRMC,123519,A,4807.038,N,01131.000,E,022.4,084.4,230394,003.1,W*6A
Keep unit clean and dry. Use soft cloth for cleaning; do not use solvents.
Storage: Store in cool, dry place when not in use.
Antenna Care: Ensure MCX connector is clean and tight if using external antenna.
CAUTION! Do not disassemble unit. No user-serviceable parts inside.
FCC Compliance: This device complies with Part 15 of FCC Rules. Operation subject to conditions: (1) device may not cause harmful interference, (2) device must accept any interference received. CE: Complies with European EMC Directive. For full regulatory details, visit www.garmin.com/compliance.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| No power (LED off) | Incorrect power connection | Check polarity and voltage; ensure wires are secure. |
| Red LED on (no fix) | Poor satellite view | Move unit to open sky location; wait up to 5 minutes. |
| No data output | Incorrect COM port/baud rate | Verify port settings in software; try different baud rates. |
| Inaccurate position | Multipath or interference | Relocate away from metal structures, electronic devices. |
| Intermittent data | Loose cable connection | Check all connectors; reseat DB-9 and power cables. |
Reset: Power cycle unit. For persistent issues, send factory reset command.
Support: Visit support.garmin.com or contact Garmin Product Support.