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Trig 22 and skyfx

tectweaker

Well Known Member
I assume that trig is only compatible with tn72 as the gps position source.

Wanted to confirm. The skyfx option would be much better I think to use because of all in one antenna.

I realize I can make it work if i has a efis , but this setup would be a trig display to remote transponder directly.
 
I assume that trig is only compatible with tn72 as the gps position source.
Wanted to confirm. The skyfx option would be much better I think to use because of all in one antenna.
I realize I can make it work if i has a efis , but this setup would be a trig display to remote transponder directly.

Not familiar with the Skyfx, but the Trig TT22 work fine with GRTs Safe-Fly GPS.
That's the combination I used on my RV-6.
 
The TT22 can also work with a Garmin 400, 500, 650, 750, etc series gps navigator by reading its ‘ADSB+’ RS232 format. Note, this is without regard to efis/no efis. To avoid unwanted time delays the gps has to be wired directly to the TT22.
Edit. You need the waas version of these navigators.
 
Trig 22 directly to skyfx

Just to be clear. Can I directly connect the rs32 output from a skyfx-ext to trig 22? That is what I am after. This allows me to not have to mount a receiver such as a tn72 or other. Just one less piece to install.

I don’t have a efis in this setup nor another waas gps.
 
Last edited:
Short answer = call uAvionix & Trig, both
Longer answer = Skyfx appears to only output NMEA 0183 V4.1 + RAIM.

Trig TT22 installation manual indicates the following:
5.6.9 GPS Position Input
The GPS position input is required to support ADS-B functionality. The GPS
position input is an RS232 input to the transponder. The ADS-B features are
optional – no GPS is required for normal Mode S Elementary Surveillance.
The TT21/TT22 GPS input can recognise the following protocols:
· Industry standard “Aviation” protocol
· NMEA 0183 protocol ($GPRMC sentence is required)
· Freeflight and Accord NexNav GPS proprietary protocols
· Garmin ADS-B protocol, including ADS-B plus
· Trig ADS-B protocol
· C199 TABS compliant GPS using NMEA protocol
· Trig TN72 GPS protocol
The interface speed can be selected between 4800, 9600, 19200 and 38400
bps.
Some of the protocols listed above may not contain all the required data for a
compliant ADS-B message, depending on the intended airspace regulations.
For further information refer to Section 12 (ADS-B Compliance) of this
manual.

The questions you need to get answered by the two respective vendors are:
1) What information exactly is output by the Skyfx - does its output contain the $GPMRC sentence? Is this sufficient data to meet the US ADSB requirement? Or is this output data from the Skyfx in compliance with C199 TABS?

2) Does Trig have a different or updated way of stating their interface protocol requirements? Note their list does not specifically address Garmin's proprietary ADSB+ when in fact we know this protocol works with the TT22 to achieve FAA ADSB mandate requirements.
 
? Garmin ADS-B protocol, including ADS-B plus

?
2) Does Trig have a different or updated way of stating their interface protocol requirements? Note their list does not specifically address Garmin's proprietary ADSB+ when in fact we know this protocol works with the TT22 to achieve FAA ADSB mandate requirements.

Yes, Trig works with Garmin?s ADSB+ protocol, but yes, it is on the list (see above). They just spelled out the word ?plus?. (I am curious if Trig bought a license, or reverse engineered it.)
 
In conversation with an engineer there I was told it was reverse engineered.

Thanks, Bob, for fixing my "quick scan" reading error.
 
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