Lancair Transponder constantly cycles with clicking sound

[flyblueskies 143]

I've replaced the F1 GTN 750 with the Reality XP GTN 750 and noticed a clicking sound. It turns out the Transponder cycles the code continuously and is the source of the clicking sound. If I return the GTN back to the F1, the transponder does not cycle anymore and the clicking sound is gone.

I'm using the built in replacement via the ADD-ON from the main P3DV4.4 menu...

I've done a little searching here at AVSIM, but I have not found any solution yet...

Has anyone else found the solution to the (Realair) Lancair XP GTN 750 clicking/transponder issue?

[Bert Pieke 7,585]

Just tried it.. and did not notice any transponder issues..

If your F1 GTN at the 2.09 level?  (in which case it uses the same trainer release..)

[flyblueskies 143]

Thanks Bert,

I noticed you mentioned F1 GTN...I'm not sure if this is a typo or not...I'm switching out the F1 GTN (which does not have the problem) to the Reality XP GTN 750 (which does have the problem).

I'll double check version 2.09 for the Reality XP GTN 750. I don't recall updating any of the XP Reality GTN databases, but it is possible.

[flyblueskies 143]

I have more information...

I'm currently running Reality XP GTN 750 version 2.5.10 and I believe the GTN Trainer is the same (not quite sure how to check this, but that is the version I downloaded and installed).

I think I 'fixed' the transponder issue by restoring the F1 GTN 750, exiting P3DV4.4. I then started P3DV4.4, added the Reality XP GTN 750 to the Realair Lancair (V2 for P3dV4.4) via the Add-ons menu.

I then changed planes to another allowing it to show in the flight sim. I then chose the Realair Lancair again and the cycling of the transponder is gone. So, all good on that front.

However, I still have the clicking sound, which occurs every 1 second. Not a deal breaker, but annoying...

I think many have reported this, although not necessarily in regards to the Reality XP GTN 750. So, I'm not sure if they are related or not...

[flyblueskies 143]

I changed the name of "switch_small.wav" to "switch_small.wav.OFF", which is located in the "\Lockheed Martin\Prepar3D v4\Sound\' folder. So far, this stopped the clicking noise with the Legacy Lancair V2 when using the RXP GTN 750.

[RXP 2,338]

Hi,

most likely it is something trying to change a 'simvar' every second, and, the aircraft gauge looking at the change 'triggers' the sound in response. The question remains: what is changing every 1 sec? 

Renaming the sound file prevents from hearing it and probably, there is nothing adverse in doing this as it seems the sound gets played only when a condition changes, probably from the GTN, and the aircraft seems fine with it!

I'd suggest you use the latest GTN v2.5.12 released yesterday though, it fixes a certain number of things.

[flyblueskies 143]

Thank Jean,

Yes, I agree...simply stopping the sound, but not really solving the problem. I've downloaded the update, but I'm not sure how to go about updating...do I need to uninstall first and then update?

[fppilot 4,370]

41 minutes ago, flyblueskies said:

Thank Jean,

Yes, I agree...simply stopping the sound, but not really solving the problem. I've downloaded the update, but I'm not sure how to go about updating...do I need to uninstall first and then update?

Just install the update(s). That's all you need. It/they take(s) care of it! Preserves some important stuff, especially your stuff like stored flight plans and any nav database updates, and replaces what it/they need(s) to replace!

You don't have just one do you! <grin 🙂

Edited February 10, 2019 by fppilot

[fppilot 4,370]

46 minutes ago, flyblueskies said:

Thank Jean,

Yes, I agree...simply stopping the sound, but not really solving the problem. I've downloaded the update, but I'm not sure how to go about updating...do I need to uninstall first and then update?

Save some time and frustration. Do you have any repaints to deal with? If not you might remove the model and reinstall. Make backup copies of your .ini and .cfg files but leave them in your backups/archives.  Then reinstall the Lancair and verify the installation is good. Then add back the RXP GTN 750, creating new .ini and .cfg files and see if it solves the issue.