Transponder stopped working

[cperry]

Hi,
My SV-XPNDR-261 was functioning perfectly...and then one day not (getting red X). Its worked again briefly since the first time it failed, but not since. I've checked the following:
- power & ground at transonder
- continuity in comm tx & rx lines
- continuity in jumpers
- pin alignment/bent pins/unseated pins
- disconnect switch
- Transponder Setup - Status (now shows Not Found)
- Serial Port 1 Config - Set to Dynon XPNDR, Shows Tx Counter, but nothing on Rx Counter.
Have I missed something...or am I just the unluckiest guy on the block when it comes to experimental electronics? lol
Chris

 

[dynonsupport]

So the fact that you're not getting anything on the rx counter means that for whatever reason, the transponder is not sending data back to the Dynon. It could be because it's not receiving power, or the tx wire from it isn't connected, or it's not working. If you're fairly certain about the wiring, get in touch with tech support at 425-402-0433 or at support at dynonavionics dot com, and they can work with you to figure out if it's the unit.

 

[cperry]

Talked to Tech Support...switched xpndr to a different serial port, problem solved. I'll report this back to Dynon Tech Support.

 

[jbeaver]

So, are there particular serial ports that we either should or shouldn't use with the transponder?

 

[dynonsupport]

At this point we don't have enough data to know what the exact cause is, so we can't recommend a serial port. Our expectation is that it's a software bug and it's our top priority to get it fixed ASAP. Right now we're struggling to re-create it here.

If you are having an issue and need a fix right away, our best suggestion is this:

If you are on serial port 1 or 2, move to 3 or 4, and if you are on 3 or 4, move to 1 or 2.

If you are on 5, move to 3 or 4.

 

[cperry]

Oh, here's a little tidbit that might help...I moved the transponder from serial port 1 to 2.
(ref case #75031)

 

[dynonsupport]

A little more info on workarounds: In addition to moving the serial port, disconnecting the backup battery should fix this issue. As previously mentioned, there's a software bug here. We're still working to fully understand it.

 

[flaude]

this is maybe why I have some problems.

It work sometime but not always! usually start to work but after 5 minutes stop! I am on serial port 2. I have 2 10inch screens, so I imagine that when I will change it I will have to remove the 2 battery back up.

 

[rickw]

Odd enough...my gtx327 worked like a champ with mode c, and showed on my skyview for the first 60 hours. Got back from osh, updated the firmware to 3.1.1 and immediately I have lost mode c. I also get a lot of clicking in headsets...traced back to the skyview. I will check all wires...but very odd that in all these hours no issue and now with a firmware the feed from the skyview is TU and causing noise. Any chance its a software issue before I tear stuff apart??

Odd coincidence?

 

[mmarien]

Same here. My GTX327 altitude (mode C) stopped working about two weeks ago. Suspiciously about the time of the 3.1.1 update but could have been the 3.1 update also. The SV serial port shows transmissions but my GTX327 firmware is too old to show the serial port input in setup mode so I can't trouble shoot other then to observe that the altitude is not displayed. Tower said no joy on the mode C the other day. The mode C works intermittently as I have seen pressure altitude a couple of times on the GTX327 since the 3.1/3.1.1 firmware update but it's otherwise conspicuously missing. I have:

SV Serial 1:  GTX327
SV Serial 2:  GPS495
SV Serial 3:  ZAON
SV Serial 4:  none
SV Serial 5:  SV-GPS-250

The ZAON was added at the same time as the 3.1/3.1.1 update.

I got rid of the clicking by removing the SV audio connection from my intercom. I don't remember the clicking before the 3.1/3.1.1 update. The manual does specify to NOT connect the SV audio.

 

[dynonsupport]

Guys,
Just late last week we found an issue in 3.1.1 that can disable serial ports 1/2 in some cases. We just put up a page describing it, and what to do until we get a new software release out. Sorry for the trouble:

http://dynonavionics.com/docs/news_311SerialPorts.html

 

[rickw]

Ummmmm

So, my mode c is gone T/U due to version 3.1.1 bug... You know about it and the work around is to disconnect the back up battery. Wierd but I will give it a try.

Thats kind of funny...in a not so funny way. Will look forward to new release to get this back on track. I will post tomorrow if disconnecting the back up battery brings my mode C transponder broadcast back on line so ATC stops telling me its not working ;D

 

[mmarien]

I pulled the backup battery plug today and the xponder was receiving pressure altitude from SV again (serial port 1). I did notice that SV reset when I started the engine. The starter probably pull the voltage down too much. This wasn't a problem with the backup battery.

This bug doesn't seem to affect the GPS495 connected to SV serial port 2. AP was following the DTO from the GPS495 the last few days while the xponder Mode C wasn't working.

 

[rickw]

Transponder MODE C stopped working

TEMPORARY FIX- it worsk.

So, as detailed above I tried BUG temp fix as dynon tech suggested until they fix the bug. I disconnected my dynon back up battery and sure as can be my garmin gtx327 mode C came back and worked. Thats kookie.

AND, the horrible clicking in the headset is gone. One odd side affect is that when I power up the panel for the first second or two it looks like its frying.. all these wierd white lines and coloured pixels and then its fine.

SO please DYNON fix this bug soon as I need mode c working on my transponder and disconnecting my back up battery whey I fly with a glass panel and no backups (yes just vfr) is not my first choice.

 

[mmarien]

I'm getting the same weird screen on boot. It also seems to take longer to boot. That may just be anticipation because of the weird boot. It doesn't happen with the backup battery connected. I just think of it as Dynon rhapsody .

 

[Harry]

I upgraded from 2.5 to 3.1.1 yesterday because of just finishing up a new panel install.  I have booted the screens many times on the bench and a few times in the airplane with version 2.5 and earlier and everything has been perfectly normal.
Only one of my screens has a back-up battery.
I noticed during 3.1.1 install, that the screen without the battery had all the white and colored lines (as you described) and took longer to boot up.  It also seems to be noisier and making different sounds than the screen with the back-up battery.
I haven't configured or tested anything, so I don't know if I have any problems yet.
Just thought I would pass along this info hoping it might help with finding the problem.  

 

[flaude]

I did the modification and it is working. Serial now is 3. do not forget to modify in the setup menu the use of serial port 3 instead of 2!!

As I have 2 SkY10 UI have to modify the setup in both screen

thank for the info

I was ready to do again my wiring. that solution was much more effective!!

 

[rickw]

So big question..when do we get the fix. I fly with vfr one glass panel and now to keep this working I have disconnected my back up battery and have funky screen on start up. It kind of spooks me a bit as I am planning on a few bigger cross countries in the next few days. I dont want to rewire the transponder to diff serial ports, thats a ton of work at this point. Are we hoping that SEPT the firmware will fix this bug and my start up screens will be normal, the wierd clicking in headsets gone adn that I can plug in my back up battery AND my mode c will work. That would really be great...local flights like this are ok..long cross countries not really....

 

[dynonsupport]

The September release fixes the serial port issues and allows you to re-connect the battery. It will not likely make any difference to the clicking in your headset.

 

[rickw]

PLEASE give us the software update so I can get my back up battery back on line.

Been anxiously awaiting..... Please... :-/ Soooooooon????