On Friday, February 3, 2017 at 4:13:14 PM UTC-8, wrote:
For an experimental glider, its allowed to connect any GPS to your Trig22, and broadcast adsb-out as a 'non performing emitter'. I use my LXNav flight computer as a gps source, its a one-wire connection to the Trig. Be sure to go through the Trig setup and select an 'unapproved gps'. If you have problems, ask Trig, they were very helpful to me.

Sadly, I understand ATC will not presently relay the positions of non-performing-emitters to other aircraft, but big planes will see my Trig22 anyway. But a cheap certified GPS will come along. I'm still waiting to hear the actual cost of a TN72.

In my opinion, transponder and adsb is the best way to invest money, for gliders in the USA. Flarm is arguably better now, but that will change as lower cost adsb systems surely come along. The clinching argument (to me, that I read here on RAS) was to hear that Flarm is not useful in a gaggle, only to warn of gliders approaching the gaggle.

Flarm is quite useful in a gaggle, while ADS-B will be completely useless. If there are 20 sailplanes in the gaggle, then just about anything looks pretty cluttered, including the view out the window. With 10 or less in a gaggle, and a good tactical display, you have excellent situational awareness.