On Thursday, August 6, 2015 at 8:02:41 PM UTC-7, Bob Gibbons wrote:
Just curious, what would be the advantage of this unit over using the
1090ES out capability of the GPS source in a PowerFlarm?

/snip/

Let be clear on terminology. The PowerFLARM itself has no 1090ES Out capability. it has a NMEA GPS Output that can be connected to some ADS-B Out devices, including Mode S/1090 ES Out transponders like the Trig TT-21/22.

You ultimately can't use the GPS source in the PowerFLARM to drive ADS-B Out and get all the ADS-B benefits. Doing that will not meet any 2020 Carriage Mandates (for power aircraft, or possibly glider corner cases like Class A airspace), and not if you want to receive ADS-B based ground services.

You certainty cannot install ADS-B Out in a certified aircraft, including glider, with anything like a PowerFLARM GPS source. And even if you do that in an experimental aircraft now you will likely start receiving letters from the FAA cautioning you about operating a non-compliant ADS-B Out system.

PowerFLARM does not even speak the a necessary serial GPS protocol to enable use for a ADS-B GPS data source (you need "Aviation format", not NMEA), let alone have all the RAIM support needed to meet TSO-C145c type requiremnts. (TABS class B GPS sources would reduce those requirements.. if TABS is adopted, and if it's installation/use regulations are sensible).

Nothing stops somebody today with an *experimental* glider connecting an NMEA GPS source to an ADS-B Out device as long as parameters like SIL are correctly set to indicate the degraded GPS source. And proper installation tests etc. are done. But you better know what you are doing, and be aware of the implications.