Own position without GPS fix

[scsirob]

Just a thought.. Assuming that those interested in PilotAware are a bit tech savvy, I would think many are feeding a GPS signal into their transponder so they too are transmitting their position through ADS-B Extended Squitter. That may well be an independed GPS signal of much higher quality than the dongle/rosetta can provide.

If this is the case, then I'd think PilotAware can use the plane's own ADS-B signal to establish position, even if the GPS dongle fails to provide a decent fix. You already need to fill in your 24-bit identifier anyway, so when you receive your own transponder, it will have your exact position included.

This way you may have redundancy in GPS location.

What do you think?

[exfirepro]

Hi Rob,

Technically feasible, but I’d have to say that in my experience, the GPS fix provided by PAW’s WAAS/EGNOS GPS is generally extremely reliable and as good or better than most readily available (uncertified) alternatives, so not sure we’d have anything to gain by this.

Interested to hear others’ opinions though.

Regards

Peter

[Ian Melville]

The gain will be that the transponder can use Sil=1

My restoration project has a Trig transponder and I was thinking of adding a TN72. If it could also feed the PAW, that would be great.

Trig Manual states:

The GPS position output is an RS-232 compatible port operating at 9600 bps. It should be routed to the appropriate GPS position input on the transponder. The data format is NMEA compatible with proprietary extensions. It can be used as a position input for any NMEA compatible equipment.

Looks promising but need more detail of the NMEA sentances sent.

Cheers
Ian

[Admin]

You could do this today over rs232
Set the gps feed as ‘flarm in’

Thx
Lee

[Giver]

Like Ian i also was toying with fitting the TN72 in the new year and like the idea of using it for the
rosetta,
As my new GPS Antenna will have a unobstructed view of the sky it should improve the number of satellites picked up by my rosetta that’s permanently fitted in the rear fuselage,
should be a win/win