Garmin Jack

I'm wiring things up right now with the intention of using a Garmin handheld to drive my TruTrak ADI. The ADI has a single wire for this purpose that I would like to wire to a panel mounted jack. Can anyone tell me exactly what type of jack this would be?

Steve Zicree
RV4 with a whole bunch of spaghetti behind the panel

Hi Steve,

You need to buy the $25.00-30.00 "Garmin Data Cable" available a lot of places on the net. It looks like the same plug, but is proprietary to the Garmin. They are cheap, and allow you to basically plumb the thing into ship power and the ADI. We've done a bunch of TruTrak stuff to the handheld garmins, and those little data cables are the easiest way to go.

Cheers,
Stein.

RE Garmin Jack

I assume that you want a panel jack to allow you to plug the Garmin handheld in.

You can install a DB-9 connector onto the panel, and wire a mating connector to the end of the Garmin-purchased data cable.

Another technique that I have seen is to use a mono or stereo audio jack on the panel to handle the data lines and ground, with a mating plug wired to the Garmin data cable. (This is done by Rocky Mountain Instrument for example).

Independently of the Garmin - ADI connection, you may have other instruments that need serial data links (such as the Dynon D10A, engine monitors, etc.) to allow for data logging or software updates. Rather than have a connector for each instrument, you can have a toggle switch or rotary switch to select the instrument you want to talk to, sharing one connector.

In the big scheme of things, I kind of like the idea of the audio jacks -- they are small, need only one hole to mount, and are cheap. You can sprinkle them over your panel to connect into any instrument you want.

Vern Little
www.vx-aviation.com

Connecting 2 GPS units to an autopilot

I have a SkyMap II driving a DigiFlight autopilot. I would sometimes like to have it track my Garmin 196 handheld. (which already draws power through a power/data cable.)

My question is, can I wire the NEMA output wires from each GPS to a 2 position toggle?
That way I could choose which GPS drives the autopilot?

Seems simple, but I am electronically challenged. Thanks,
Mark
RV-6

Your question about driving your AP from multiple sources is actually quite common and quite easy to do and something we do for people quite frequently.

With the single level AP's that use only 1 wire for the RS-232 signal such as the TruTrak or Trio units, you simply need a Single pole, Double Throw (SPDT) switch that is On/On or On/Off/On. A good one to use is a miniature toggle as it barely takes up any room in the panel.

Here's what you do.

1) Run the RS-232 sense wire for the AP to the center terminal on the back of the switch.

2) Run a wire from each of your GPS's to the outside 2 terminals on the back of the switch....one wire for each unit to a specific terminal....not both units to both terminals.

That's it. When you select one position or the other, you'll be selecting either unit to drive the AP. If the switch is on/off/on the center position will be off, but with an On/On switch you'll only get 1 or the other unit driving the ap.

The switches are cheap and available many places. I think we sell them for a couple bucks, but you can get them at your local rat shack store as well.

Hope that helps.

Cheers,
Stein.

Hey Stein,

I went online and found the data cable you spoke of. It looks like it has three bare wires poking out the end of it. I'm assuming one for juice, one for ground, and one for the RS-232. Any reason why I can't attach a little audio plug to the RS-232 part and a cig lighter plug to the other two? I've already wired up a cig lighter socket under my panel, and would like to have a little audio jack right there too. I guess I should ask how many volts the Garmin needs also.

Steve Zicree

Connecting 2 GPS units to an autopilot

Thanks, I found an on-on mini toggle to connect the 2 GPS units.
Mark