Cheapest solution for Mode C Transponder and ADS-B?

[TFF]

I thought the Navworx GPS was using some sort of future protocol. There are ADSC and ADSD specs on the table. I was under the impression that Navworx used one of those and the FAA can’t read, for a lack of a better term, the “cookie”of the GPS. Missing bit or something that was not functional but ID related.

 

[Built2Fly]

If there is no penalty or citation from out of spec GPS source, I guess I can give it try. But that has to wait a few years when I have something built to fly.

 

[rv7charlie]

I didn't say there was no penalty; I said that I hadn't heard of anyone getting violated. Yet. Like when you passed that cop going 10mph over the speed limit, but he didn't want to get out in the rain to give you a ticket.
But intentional violations of the FARs tend to get the FAA's attention and they don't have to get out in the rain to cite you.

I should say that while they aren't violating people yet, they *do* send ADSB performance failure notices all the time. The 'system' knows about every failure, and records it (along with the rest of every flight; chew on that....).

 

[Built2Fly]

@rv7charlie, I know that the ADS-B mandate is scary as the "Big brother is watch". This is pretty much like putting a GPS tracker on my car and tracking every friends I have visited without a warrant. Talking about that, I agree with you that the anonymous mode is very important.

Back to the topic of GPS testing. From what I understand, all the WAAS are pretty much same on accuracy. The difference is the anti-spoofing information it sent out. This should be even less harm even than driving 10mph over the limit (which we do everyday). As an experimenter, I think it worth it to give it a try.

 

[TFF]

From what I understand anonymous only keeps flight aware and others from broadcasting your N number. The FAA still knows.

 

[Built2Fly]

Don't you use a random ICAO number (in additional to a random N-number) when in anonymous mode? What else are they track you with?

 

[BJC]

Don't you use a random ICAO number (in additional to a random N-number) when in anonymous mode? What else are they track you with?

Anonymous only operates with code 1200. TFF is correct.


BJC

 

[GeeZee]

Anonymous only operates with code 1200. TFF is correct.


BJC

Not quite correct, while you are squawking 1200 in anonymous mode you are anonymous to everyone even the feds.
As far as flightaware goes I can flip the switch on my GDL-82 to anonymous mode and Flightaware looses me.

 

[BJC]

Not quite correct, while you are squawking 1200 in anonymous mode you are anonymous to everyone even the feds.

Yup, I had it wrong.

Thanks,


BJC

 

[Toobuilder]

Yup, I had it wrong.

You might be thinking of the half assed privacy scheme for 1090ES users. THAT one scrambles the registration data to outsiders, but the basic info is still delivered to Big Brother in its pristine state.

 

[Built2Fly]

Just record my findings (after a lot of asking and digging) here in case someone needs it in the future.

According to Uavionx, the echoUAT has 3 approved GPS sources:

• Uavionx SkyFYX;
• Garmin GNS series with the latest ADS-B firmware;
• GRT SafeFly 2020.

All other GPS sources are unsupported. They would not provide further technical support if un-approved GPS sources are used (which is fair).

All GPS sources should meet NMEA 0183 + RAIM standard. The entire system certification meets FAA RTCA DO-282B.

• According to this document on Uavionix website, the Uavionix GPS seems to use a protocol that include some specific proprietary messages probably for the RAIM functionalities. hhttp://uavionix.com/downloads/truFYX/truFYX-NMEA-ICD.pdf
• Other GPS sources (Garmin and GRT) probably used the standard RAIM protocol from NMEA 0183. RAIM is for GNSS satellite fault detection, and is transmitted by NMEA GBS sentences (as documented here NMEA-0183 message: GBS)

If anyone knows any good RAIM capable GPS chips or modules, it may worth it to have a try. Otherwise, it may be easier to just use one of the approved sources.

 

[rv7charlie]

So, answer #21?
;-)

Seriously, I haven't kept up with the 'in the weeds' stuff since I'm not IFR rated, but I thought that for non-WAAS approach GPSs, RAIM was an original requirement , and WAAS capability superseded (replaced) the RAIM function for approach GPS. Any of you cloud busters know if that's correct?

Assuming it is correct, it's interesting that RAIM would be needed for ADSB.

Charlie

 

[TFF]

To me it looks like RAIM is a system check to the FAA that your WAAS is functioning during your approach. I think it’s an airliner requirement.

 

[Built2Fly]

Wikipedia on Receiver Autonomous Integrity Monitoring (RAIM) - Receiver autonomous integrity monitoring - Wikipedia

 

[ToddK]

If you already have a mode C transponder and tray, then a uavionx kit would make the most sense. If you don’t have a transponder, then by the time you buy one, get a tray, and have it checked out you might as well have gotten an ES transponder for experimentals. Trig seems to be the best value. Do the math, and don’t forget the value of a simple and very small installation.

 

[Daleandee]

If you already have a mode C transponder and tray, then a uavionx kit would make the most sense. If you don’t have a transponder, then by the time you buy one, get a tray, and have it checked out you might as well have gotten an ES transponder for experimentals. Trig seems to be the best value. Do the math, and don’t forget the value of a simple and very small installation.

I have a Garmin 320A transponder without a tray. Works well and saves weight. Planning to add the uavionix echo bundle soon. Transponder and encoder were gifted and the bundle is currently at $1400 ...

 

[rv7charlie]

Wikipedia on Receiver Autonomous Integrity Monitoring (RAIM) - Receiver autonomous integrity monitoring - Wikipedia

And WAAS:
Wide Area Augmentation System - Wikipedia

 

[Toobuilder]

Just be eyes wide open with a 1090 ES setup. No anonymous mode at present. If that's not an issue, then your options are better than mine.

 

[Rik-]

Where is everyone purchasing their "used" avionics" from?

 

[FinnFlyer]

@FinnFlyer, I'd love to see your code. I am interested in the format of the message and the setting on GTX-327 to receive that. I found it hard to find those information. Maybe we can document the working combination here in case it is needed by someone later.

You shouldn't need a serial to gray encoder with the GTX327.

From this post: https://vansairforce.com/community/showthread.php?t=166994
"I connected the Encoder Out wire from the Dynon to Pin 19 of the GTX-327 ... I programmed the ALTENC setting on the Dynon to "Format 4" for the GTX-327, and on the transponder, set "RS-232 Input CHNL 1" to "Icarus" per the manual. "

Finn