Aug 6, 2018

Yaesu FT-991A with GPS

I'm not sure why, but the Yaesu FT-991A does not come with a built-in GPS unit. So if you want that data included in digital QSO's, you will need to connect your own external GPS antenna. Now comes the Garmin GPS18x PC, a fully compatible NMEA GPS, WAAS enabled antenna that connects to the FT-991A's GPS/CAT DB9 serial port. Power is supplied by a 12 volt plug into my Yaesu FP-1030A power supply.
Setup is pretty simple with radio menu 028 set to GPS1, which is the the default setting. Plug it in, and turn it on. Wait, slow down. Did you get that?

Now when you key up on a C4FM repeater - as well as with a few other functions - your location/distance is also transmitted/received for the other stations. And if it makes your day, you get the cool little green GPS satellite icon showing up on the FT-991A touchscreen. Nice!

Update: Oct 2020 

With a Powerwerx PowerPole-to-cigar lighter adapter, I plugged this into my RIGrunner 4007U because I kept hitting the plug sticking out the front of the power supply. This GPS is working great!


  1. It looks quite usable, except I don't have a 12v port in my house and I'm not planning on using my 991 in a mobile configuration.
    Any suggestions?

  2. Hello,
    it doesn't work for me, the antenna is inside by the window. Does it have to be outside ??? you have some experience ??
    73 , Greg SP5LGN

  3. Hi,
    next step, you need to change the menu item 029 to 4800bps, now it works fine,
    73, Greg, SP5LGN

  4. Can you enter coordinates manually ?

    1. Yes. In the user FT-991A manual, bottom half of page 112, there are full instructions.

  5. Is the 12 plug actually necessary for the 991A? The radio's DB9 pinout indicates pin 5-ground and pin 9-RI with voltage on the latter. Has anyone tried without plugging in the separate power?

  6. Some units aren't wired for power on the db9 for some reason. I've noticed that myself when I was looking for a unit. I had to use the 5v output on my power supply