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GTR200B not breaking squelch

Still no resolution or suggestions from Garmin. I think they gave up on us. It very strange, but at times the frequency will not break squelch on the active side of the radio. If that same frequency is on the monitor side, it comes in loud and clear, switch it to the active side and it goes silent unless you turn off the auto squelch. Its very frustrating.

There are three of us with the same issue. So far we have swapped radios, we have different pathways for the coax, different antennas. The common denominator seems to be mounting the radio next to the Garmin 375. But I can’t confirm this is the issue, just a guess.
 
This is from some back and forth with Garmin a long time ago when I asked about standby sensitivity:

Question:
Radio does not break the squelch in active (no RX), but breaks it in standby/monitor. Squelch Setting is 00

Answer:
I spoke to the radio design guys and received this input.*

*The radio is most likely working as designed.* When the standby channel monitor is enabled the radio is more sensitive on the standby channel.* So, if conditions are just right a weak signal will break squelch on the standby channel but the signal will not be strong enough to break the active channel squelch.

If you feel this is not just a somewhat rare borderline condition and otherwise works fine in actual use, let’s talk some more.

(I dropped it at that point)
 
This is from some back and forth with Garmin a long time ago when I asked about standby sensitivity:

Question:
Radio does not break the squelch in active (no RX), but breaks it in standby/monitor. Squelch Setting is 00

Answer:
I spoke to the radio design guys and received this input.*

*The radio is most likely working as designed.* When the standby channel monitor is enabled the radio is more sensitive on the standby channel.* So, if conditions are just right a weak signal will break squelch on the standby channel but the signal will not be strong enough to break the active channel squelch.

If you feel this is not just a somewhat rare borderline condition and otherwise works fine in actual use, let’s talk some more.

(I dropped it at that point)

Huh, Well that is interesting. The problem is that the active side is so insensitive that we are losing audio when clearly in range. If you take off the squelch the audio comes in very loud and clear. I can’t quite explain it, its like the squelch value is turned way up on the active side, but its set at the lowest value. Its lead to several embarrassing lost commo events.... Either that or I fly around like I am listening to and HF frequency with the auto squelch off.
 
Not an install into a RV but I too have a 200B doing this same exact thing. Mine seems to work fine for about 20-30 minutes then starts doing the same thing you guys describe. I'm an avionics guy and have checked all the usual things. I have eliminated headsets, antennas, grounding, interference with other electrical components etc. Makes me nervous about flying in controlled airspace because I would have missed calls for sure.
I wish there was a known good loaner 200B I could try on my next flight. I'm happy to loan my known bad one out.
I might add, my setup is a G3X, GTX 335 and GTR 200B. I do not have an autopilot controller or IFR Navigator. For an antenna I am running a Comant on the bottom.
 
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I’m currently waiting on a software update for my nav/com test set or I’d offer to do the testing, not rocket science to test sensitivity.

Sensitivity:
SINAD greater than 6 dB when the RF level is -107 dBm with 30% modulation
 
Only one radio.
I think the question is “did you inadvertently connect the 200B desense line”? (TX interlock)

It would be incorrect to utilize it for a single radio install, and really bad to hook it to a continuously operating transponder (or hard tie it to ground).

It’s pin5 on the 200.
 
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Not an install into a RV but I too have a 200B doing this same exact thing. Mine seems to work fine for about 20-30 minutes then starts doing the same thing you guys describe. I'm an avionics guy and have checked all the usual things. I have eliminated headsets, antennas, grounding, interference with other electrical components etc. Makes me nervous about flying in controlled airspace because I would have missed calls for sure.
I wish there was a known good loaner 200B I could try on my next flight. I'm happy to loan my known bad one out.
I might add, my setup is a G3X, GTX 335 and GTR 200B. I do not have an autopilot controller or IFR Navigator. For an antenna I am running a Comant on the bottom.

Hi Eric,

Dan and I have both tried brand new 200’s, and got same results, so I wouldn’t bother. You are now unfortunately the 4th person experiencing this problem. Garmin has stopped responding to our emails and told me yesterday when I called that Dan and I are the only ones reporting the issue.

Feel free to PM me if you want and I can add you to our group text to share troubleshooting ideas.
 
Have you guys verified there is no pin in #5, that’s the interlock input (desense).
 
GTR 200 Software Revision

We are taking a look at a radio from one of the problematic installations, to try and recreate the reported issue. We will pin down whether it is a configuration/setting issue, an installation issue or an equipment issue. At this time we do not know exactly what the problem is so we do not have any guidance for resolving the issue. We will make sure to respond here when we have everything sorted out.

Thanks,

Justin

We have been working throughout the holiday period, and into the first of the year, to recreate this issue. We were able to at least in part replicate the reported behavior, and subsequently improve performance of the GTR 200 through a software revision. Additionally, we've implemented some software based improvements to the monitor mode function.

We're currently working through flight testing of the software revision, when that testing is complete, the update will be made available to the field. We will leave an update on this thread when the software is available for download.

Thanks,

Justin
 
I think the question is “did you inadvertently connect the 200B desense line”? (TX interlock)

It would be incorrect to utilize it for a single radio install, and really bad to hook it to a continuously operating transponder (or hard tie it to ground).

It’s pin5 on the 200.

Pin 5 is empty
 
We have been working throughout the holiday period, and into the first of the year, to recreate this issue. We were able to at least in part replicate the reported behavior, and subsequently improve performance of the GTR 200 through a software revision. Additionally, we've implemented some software based improvements to the monitor mode function.

We're currently working through flight testing of the software revision, when that testing is complete, the update will be made available to the field. We will leave an update on this thread when the software is available for download.

Thanks,

Justin

Awesome Justin! Glad to know at least we werent crazy. Thanks for update!
 
We have been working throughout the holiday period, and into the first of the year, to recreate this issue. We were able to at least in part replicate the reported behavior, and subsequently improve performance of the GTR 200 through a software revision. Additionally, we've implemented some software based improvements to the monitor mode function.

We're currently working through flight testing of the software revision, when that testing is complete, the update will be made available to the field. We will leave an update on this thread when the software is available for download.

Thanks,

Justin

Best news I’ve heard all day. Hopefully this fixes the problem. Thanks Justin
 
GTR 200 Software 3.40

GTR 200 Software version 3.40, which includes the improvements made to address the issues raised in this VAF thread, has been released to the GTR 200 Software Download area today. This software version will be included in the next G3X Touch software package, but until then, the GTR 200 can be updated individually using this link.

Instructions for updating software on the GTR 200 can be found on page 3-20 of the P Revision of the GTR 200 Installation Manual.

Thanks,

Justin
 
GTR 200 Software version 3.40, which includes the improvements made to address the issues raised in this VAF thread, has been released to the GTR 200 Software Download area today. This software version will be included in the next G3X Touch software package, but until then, the GTR 200 can be updated individually using this link.

Instructions for updating software on the GTR 200 can be found on page 3-20 of the P Revision of the GTR 200 Installation Manual.

Thanks,

Justin

Thanks Justin! Sure hopes this solves the problem. Fingers crossed!
 
Initial Results Looking Good

We updated our GTR 200 with the new software today and flew a quick test flight. I checked in with our local approach control and flew directly away from their location, doing radio checks every 5 miles. The radio acted completely normal with good coms out to 60NM. I need to do a proper IFR cross country to verify that all is completely good to go but the software fix is looking very promising.
 
On that same note, does anyone know if the GNC 355 has an interlock. It is not documented in any Garmin manuals.
 
I updated my software and also performed another inspection of my installation just to be sure nothing I did was causing the issue. I did find less than ideal grounding of my antenna. I went as far as adding a ground strap to just to be completely sure.

I have 2 flights and the issue seems to be gone. I can't 100% say it was the software. It could have been my less than great grounding of the antenna. Either way- it seems to be working well now.
 
Gents, did this seem to fix your problems? Had the same issue while IFR with Denver. Good thing I was monitoring guard. I haven’t done the update yet.
 
Okay. Now that we've fixed the GTR problem breaking squelch on every flight, how do we keep the passenger from breaking wind on every flight? Based on experience it's not easy starting that conversation. I'm telling ya.
 
Okay. Now that we've fixed the GTR problem breaking squelch on every flight, how do we keep the passenger from breaking wind on every flight? Based on experience it's not easy starting that conversation. I'm telling ya.

Same way as to keep a bag of Fritos from popping, which is to stay down low and thereby avoid expansion...
 
Hello -

I found this thread after searching on google for an explanation to this same issue I’ve been having with my GTR-200B. This sounds exactly like what is happening with my COM. My radio has Ver 3.30. I tried updating the software to v3.5 without success.

I’m following the instructions on the Garmin site with the microSD card. When I install the card…nothing happens. I tried installing the card with the radio on or off. Same outcome…the radio does not update.

My setup is G3x touch, G5, GNX-375, GMC507 and GTR-200B.

I also updated the G3x to latest software version hoping it would catch the radio software update as well, but no luck.

Any suggestions/ thoughts / ideas?

Thanks!
 
SAME BOAT

I also tried updating software in my GTR200B ... downloaded from Garmin, followed the wizard steps.

Same story, put micro SD card in but nothing happened. Tried every combination (off, on, etc).

Note: Extracted file copied to card = gupdate.gcx (size 554KB)
 
I see the same file details and size you shared. I have a hunch I’m missing some detailed step. Hoping someone more knowledgeable can chime in and show me my error.
 
I see the same file details and size you shared. I have a hunch I’m missing some detailed step. Hoping someone more knowledgeable can chime in and show me my error.
 
Hello -

I found this thread after searching on google for an explanation to this same issue I’ve been having with my GTR-200B. This sounds exactly like what is happening with my COM. My radio has Ver 3.30. I tried updating the software to v3.5 without success.

I’m following the instructions on the Garmin site with the microSD card. When I install the card…nothing happens. I tried installing the card with the radio on or off. Same outcome…the radio does not update.

My setup is G3x touch, G5, GNX-375, GMC507 and GTR-200B.

I also updated the G3x to latest software version hoping it would catch the radio software update as well, but no luck.

Any suggestions/ thoughts / ideas?

Thanks!

Had a similar problem when I tried to use a 16GB microSD to update the GTR200 software, turns out the radio will not recognize anything if the size is over 4 GB. The Garmin install manual "recommends" the 4GB SanDisk.

John Salak
RV-12 N896HS
 
Ah ha

I had a hunch that SD card "size" may be the culprit (especially since, like you said, Garmin recommends 4 GB).
Have ordered a 4 GB
 
Thanks for taking the time

I appreciate you all taking the time to post feedback. I will order the 4GB and try it when I’m back from travels. Will post when it’s fixed!

Happy Thanksgiving!!
 
I appreciate you all taking the time to post feedback. I will order the 4GB and try it when I’m back from travels. Will post when it’s fixed!

Happy Thanksgiving!!

You can use a micro SD card properly formatted to FAT32 up to 32 Gbyte. No need to buy a 4 Gbyte card.

I just updated one of my GTR 200 radios to V3.50 using a 32 Gbyte micro SD card.

I powered the unit on via the buss (avionics master), and not the power button on the unit…maybe that’s the difference…
It works fine to power the unit up via the power/volume knob on the GTR 200. That is how I launched my update after inserting the SD card with the unit powered off.

Had a similar problem when I tried to use a 16GB microSD to update the GTR200 software, turns out the radio will not recognize anything if the size is over 4 GB.

John Salak
RV-12 N896HS
Sorry John, this is incorrect. See above.

I also tried updating software in my GTR200B ... downloaded from Garmin, followed the wizard steps.

Same story, put micro SD card in but nothing happened. Tried every combination (off, on, etc).

Note: Extracted file copied to card = gupdate.gcx (size 554KB)
When you run the self extracting .exe file, it creates a \GARMIN folder and copies the gupdate.gcx file to that folder.

Steve
 
FAT32

I tried again with my 32GB card. Made sure it was formatted FAT32…that’s a new one for me :). Same result, meaning the radio didn’t update. I have a 4GB card on order and will reply with the outcome.
 
I tried again with my 32GB card. Made sure it was formatted FAT32…that’s a new one for me :). Same result, meaning the radio didn’t update. I have a 4GB card on order and will reply with the outcome.

Josh,

Did you execute the GTR200_350.exe file on your computer after downloading it, or try to open the GTR200_350.exe archive with something like 7 zip and extract the contents to your SD card?

After you downloaded GTR200_350.exe from the Garmin website and executed it, did you see a \GARMIN folder on the SD card with gupdate.gcx?

I have to think that you don't have a properly prepared SD card if the GTR 200 is ignoring it.

Tell us what you did and what you see so we can help.

Steve
 
Thanks to Longez Steve for the concise questions.

Yes, I followed Garmin Install Instructions. Executed the downloaded GTR200_350 app on the PC, Ran the Garmin Install wizard, selected the Drive the SD card was in and gupdate.gcx was written on the SD card.

I'm wondering now if maybe I didn't initially select FAT32 to format the card ?
Or maybe the card itself has issues?

Card is currently in the GTR200B at hangar, will retrieve tomorrow and retry formatting & download.
If that doesn't fix things, the new 4GB SanDisk card (<$10) should arrive this week and will try that.

Thanks again for everybody's help, interest & time.
 
Thanks to Longez Steve for the concise questions.

Yes, I followed Garmin Install Instructions. Executed the downloaded GTR200_350 app on the PC, Ran the Garmin Install wizard, selected the Drive the SD card was in and gupdate.gcx was written on the SD card.

I'm wondering now if maybe I didn't initially select FAT32 to format the card ?
Or maybe the card itself has issues?

Card is currently in the GTR200B at hangar, will retrieve tomorrow and retry formatting & download.
If that doesn't fix things, the new 4GB SanDisk card (<$10) should arrive this week and will try that.

Thanks again for everybody's help, interest & time.
Hi Bob,

Yes, it is a good idea to check out the card on your PC to make sure that it is not reporting errors.

Right click on the SD card drive letter in File Explorer, Select Properties, then Tools and execute the error checking tool on that page.

If I ever have an issue using an SD card, the first thing I do is run error checking with File Explorer.

Steve
 
seated correctly?

The insertion of the uSD card is a little tricky -- there is a detent to overcome in the slot and it has a push-to-eject action....

I encountered difficulty performing the update on a friends RV-12 / GTR-200 because I couldn't get enough of my fat finger on the end of the card to push it all the way in.

I suggest using a pencil eraser or similarly sized tool to push the card in...
 
It is also important that the SD card be inserted correctly with the contacts up as shown in this picture.

Correct Way to Insert SD Card.png

If you force the card into the unit with the contacts down, the SD drive will likely be damaged.

I updated a second GTR 200 to V3.50 today with this 32 Gbyte card, and it again worked perfectly.

Steve
 
Softward finally updated

Follow-up on my Software update challenge. The 4GB card did the trick. It's now on V3.5.

I did double check my 32GB card for errors. There are no errors. For whatever reason, the GTR-200b never recognized that card.
 
New 4 GB card arrived today, just did the download via the wizard and will see what happens when load into the GTR tomorrow.
Based on other's comments on success above ... confidence is high ;)
 
Moot point...

FWIW, the just released software update for the G3X Touch - version 9.12 - contains the GTR 200/B 3.50 update...finally...
 
Follow-up on my Software update challenge. The 4GB card did the trick. It's now on V3.5.

I did double check my 32GB card for errors. There are no errors. For whatever reason, the GTR-200b never recognized that card.

That’s a common limitation, it’s best to use the smallest SD card/ USB stick needed for the job when dealing with proprietary equipment.
 
bingo

Software update success ... inserted the "loaded" 4 GB, powered up and the GTR screen stepped thru the process.
Some way or another the problem must have been with the previous micro SD card.
 
Something changed...it's worse...

G3Xperts --

I loaded 3.5 into my GTR 200 (not B) and then flew this afternoon. In flight, 10 miles away from my home airport, the ATIS (118.60MHz) sounded like it was being received over another radio with background noise at the same time (the hiss of thermal energy of the noise floor); changing between SQ & RX made no difference.

I was running with 3.30 prior to today's flight without any issues.

I'd be happy to downgrade if you can provide an image/instructions.

I'll also send an email to G3Xpert.
 
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