HiIn our aircraft we want a _fully_ (meaning that it shouldn't respond to interrogations in wrong modes, pluss other minor features) functional KT76 transponder, but I have major problems getting it to work properly whenever I choose to autotune (accepting transponder code via the ATC menu) and the unit is turned off. When the unit is turned off, accepting a code from ATC makes the unit go quite mad (as observed while monitoring the variables in another gauge).What I need is either:1) Unit turned on (mode c) and code entered and displayed.2) Code displayed, but not turned on, needing 0000 as actual code.This is not for the faint-hearted, and some code may not be "up to standard" ;) (I've been working on this darn thing for quite a while).Any suggestions on how t accomplish this?The whole code of the unit is attached. Let me know if you need a full zip with graphics to understand it better.

err, bump?

>When the unit is turned off, >accepting a code from ATC makes the unit go quite mad (as >observed while monitoring the variables in another gauge).Hi Karl,I've looked at your code, but I'm simply not 'good enough' to see a solution myself. I did however, at least want to let you know that someone had at least taken the time to look! :)I've noticed that my KT76C (I thought you were working on a KT76A?) will occasionally display an "incorrect" xpndr code when squaked, but it doesn't happen often enough for me to spend time chasing that particular gremlin... :)Sorry to not be of much help, but at least I'm helping keep the 'thread' alive...

Thanks for looking ;)That incorrect displayed code is indeed the problem that is driving me mad. Shouldn't be a problem really unless you switch aircrafts during flight (which I obviously do a lot at this stage :)), at which point the squawk isn't re-"initialized" between the actual code and the displayed code. Having to work with ugly number transformations as well just add to the confusion I guess :)