Garmin GTR 225

I purchased a new Garmin GTR 225 comm radio from ACS. I'm trying to decide whether or not to use the internal intercom or to use the 2 place Sigtronics intercom I have. Has anyone had any experience with the 225 intercom and how well it works? The unit came with a wiring harness, it has only one audio and one mic connection. How would this be wired to the headset jacks? I have searched for a install manual online and apparently Garmin doesn't make it available to the public.

Garmin GTR 225 Installation Manual

I bought the GTR 225 in March 2013 from Gulf Coast Avionics to install in my RV-9A. Same problem - no manual. Called Garmin, but they would not send me the manual - dealers only. Called Gulf Coast and had the manual in my E-mail inbox 5 minutes later.

Even with the wiring harness, you absolutely need the manual to install this comm radio. Garmin shows 15 wiring diagrams. I already had a PAR100EX audio panel, so didn't wire up the intercom. The GTR 225 intercom can support pilot and co-pilot mic inputs and audio outputs.

Haven't flown the RV-9A yet, but the GTR 225 works fine in the panel. The display panel programming is impressive.

Contact ACS for the installation manual. If they refuse to send you a copy, e-mail me at eifl at rogers dot com.
Lars

I would say your best bet would be to use an independent intercom like a PSE 1000II or a 3000. While the one in the radio kinda/sorta works, the independent ones are far superior. Most good avionics shops will send you a manual when requested (if not supplied with the unit). Be careful of finding manuals on the internet, because they may or may not be the latest revision that applies to the unit you purchased.

As Lars noted, you should have the manual for any avionics you are installing - whether it has a harness or not.

Just my 2 cents as usual.

Cheers,
Stein