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Avionics shop in south FL?

jahoosafat

Active Member
Hi - I'm newly based in Miami at KTMB and my ADS-B out stopped working a month ago. I got a recommendation for Peninsula Avionics, but they installed a new Garmin antenna and then gave up when faced with the experimental setup which includes the below ...

AVIONICS
Audio Panel
Garmin GMA-240
Nav/Com
Garmin GTN-650
Transponder & ADS-B out
Dynon SV-XPNDR-261
ADS-B In
Dynon SV-ADSB-472
ELT
AKC 406-121.5
EFIS PFD1
Advanced Flight Systems 5600 (touch)
EFIS PFD2
Advanced Flight Systems 5600 (non-touch)
EFIS Engine MFD
Advanced Flight Systems 5500 (touch)
AHRS
Internal AHRS in co-pilot non-touch AFS 5600
Autopilot
Advanced Flight Systems AP

I'm looking for recommendations for avionics shops in south FL that are good and have experience working with AFS setups. Any local advice is appreciated!
 
Berkshire Instruments
Cape Coral, FLA 33990

238-485-5004 give’em a call. Don’t know if they know anything about your particular set up, but they are in South Florida and they are a FAA avionics repair station with a good reputation. I’ve had several instruments repaired and overhauled by them over the years and very satisfied with their service.
 
What documentation do you have (like avionic pinouts, what serial is used for what, how the serials are configured, etc.)?

If I worked at an avionics shop and the owner of an experimental showed up with no documentation and the only statement being “something does not work”, I’d either walk away or decide that this will be how I will pay for the vacation home….

For something like an ADS-B out (you are using the nice Dynon XPDR for this function) the AFS EFIS provides information as to data transfer and such. I suggest you review the AFS install manual as the first step toward resolving your problem.

Step two, figure out if your WAAS GPS ADS-B out data comes from the Dynon SV-GPS-2020 GPS Antenna/Receiver or a properly configured serial port on the GTN-650.

With this information (and some photos of the configuration pages) you will be well armed to engage an avionics shop.

I also suggest you ask around the field for the RV-builders. Most have done this stuff and I’ve never met any RV guy/gal that was not ready to help.

Carl
 
Thanks for all of the responses. Very helpful. Carl noted: "Step two, figure out if your WAAS GPS ADS-B out data comes from the Dynon SV-GPS-2020 GPS Antenna/Receiver or a properly configured serial port on the GTN-650." Can I determine this through the AFS Admin settings pages or do I need to physically trace the wiring out of the Dynon box? When the avionics shop that did the initial work told me they replaced the Garmin antenna located on the roof, I was a little surprised because I thought the Dynon box had a different antenna located on the underside of the empennage.
 
Thanks for all of the responses. Very helpful. Carl noted: "Step two, figure out if your WAAS GPS ADS-B out data comes from the Dynon SV-GPS-2020 GPS Antenna/Receiver or a properly configured serial port on the GTN-650." Can I determine this through the AFS Admin settings pages or do I need to physically trace the wiring out of the Dynon box? When the avionics shop that did the initial work told me they replaced the Garmin antenna located on the roof, I was a little surprised because I thought the Dynon box had a different antenna located on the underside of the empennage.

I assume you have a Garmin GPS antenna for the GTN-650 (the big, ugly white one), on the roof. Why did the avionics shop replace it? They rarely go bad. Perhaps they were “Easter Egging” and just replacing stuff as first guess.

Your AFS EFIS will list all the components it is talking to. It will also list how each EFIS serial port is configured. In the AFS install manually it tells you how to configure the Dynon GPS 2020 (or if you have the older non WAAS GPS 250) what serial port it is on. If you have the GPS 250 this means you are using a serial output from the GTN-650 for ADS-B out information to the XPDR.

Neither the 2020 or 250 should be mounted “on the underside of the empennage. Perhaps you are thinking of the ADS-B receiver antenna.

On the GTN-650 you can go into configuration mode and see how those serials are set up. From that you can deduce what is going on.

Take good notes - such information will save you many hours down the road.

Carl
 
I find it sad that some builders don’t bother with, or pass on, wiring schematics. Saves huge amount of time with something like this.
Another hint: once you figure out how to boot up the 650 in configuration mode, look at the FORMAT entry for each RS232-out port. You’re looking for format ‘ADSB+’. As far as I know it’s not used for any purpose other than adsb data to the transponder. If you find it, find the corresponding connection pin on the back, it should go to the transponder. Make sure it’s not loose or broken. If there is no ‘adsb+’ formatted rs232-out, then the transponder is probably wired to the Dynon gps for this data (if you have one-not in your equipment list)
I presume that you have already confirmed that your transponder is working? (Since it is the box actually sending the data). And also that the 650 works?
My best guess: the rs232 connection between the 650 and the transponder has a pin in the connector that is not seated properly.
 
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Thanks for that advice, Bob. Also very helpful. I do have the original wiring schematic (Stein), but I was told by a prior avionics shop that there were things that didn't match up with the actual setup. I think the builder may have made some adjustments after Stein did their work - although I'm not 100% sure about that. See here for that schematic: https://drive.google.com/file/d/0B9...are_link&resourcekey=0-BH2SrZCm90H3mg5U9sIqlg

Well, you can hope that the drawing is wrong. The transponder (which I think is a TT22 clone) must have two RS232 inputs: one from the EFIS, which I see, which will send squawk code, pressure altitude, etc. And a second RS232 input, which will accept position and velocity data from the GPS, for ADSB-out data, which I don't see on the schematic. I imagine your transponder is remote mounted. Can you see the connector? Maybe check that the pins are really snapped into place (you'd need to un-do the connector)? See if one wire (it may be shielded) goes back to the 650?
 
So here's the RS232 config: https://www.screencast.com/t/fiwJFNzd . Also, yesterday I disconnected and re-connected all of the wires/connectors going into the transponder. I didn't test to see if that fixed the ADSB out problem by flying her, but the EFIS did give me a "NO ADSB POS" alert on booting up. Oh, also, I'm emailing with Jonathon at AFS as well as leveraging the VAF collective wisdom. He hasn't responded re the RS232 config info yet, so I thought I'd post it here.
 
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So here's the RS232 config: https://www.screencast.com/t/fiwJFNzd . Also, yesterday I disconnected and re-connected all of the wires/connectors going into the transponder. I didn't test to see if that fixed the ADSB out problem by flying her, but the EFIS did give me a "NO ADSB POS" alert on booting up. Oh, also, I'm emailing with Jonathon at AFS as well as leveraging the VAF collective wisdom. He hasn't responded re the RS232 config info yet, so I thought I'd post it here.

Based on the info that you provided and in line with comments like those from BobTurner, it **APPEARS** that you have no connection between the Garmin 600 Series (Pin7, Serial 2 OUT) that has the ADSB+ info, and the transponder (which is likely a Trig TT21 or TT22).

The "good news":
This configuration of Garmin GTN 600 Series and Trig TT-21/22/31 works just fine.

Now, the "bad news" (not really THAT bad):
Looks like you need one wire added from the Garmin (may be high density pins for this, I forget) and the transponder. Configure accordingly.

With the info you have, any avionics shop should be able to do it.

As mentioned by another poster, lets HOPE that the drawing missed it and that the wire is there and it is simply a matter of configuration.

As to the antenna change, if your Garmin was doing its regular navigational duties, then your PRIOR antenna HAD to be working just fine.
 
Excellent. Thanks, James. And I don't think it matters for the diagnosis here, but the transponder isn't a Trig, but rather a Dynon SV-XPNDR-261.
 
The Dynon XPDR is made by Trig.

Did you figure out if the ADS-B position data is from the GTN-650 or a GPS 2020?

Please verify that all this worked correctly and then stopped working.

Carl
 
The fix was done by Palm Beach Avionics in under 2 hours. It was just a bad resistor at the transponder. Thanks for all of the help diagnosing and getting to this point.
 
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