GTN650 squelch issues

[Marauder]

I was notified by Garmin about Comm software update 2.20 on April 1st, 2015 & when I called 2 different Garmin dealers they advised me the Comm software 2.20 is not FAA approved yet.  It's not TSO'd, so legally they couldn't install the update in my Mooney.  Last month I checked with Epps Aviation Avionics shop, they made a phone call to Garmin & it still wasn't approved.  

I've been having the same squelch breaks at the end of incoming transmissions & range issues on the GTN 750 that I can't seem to get rid of.  I routinely monitor the GTN 650 with the same Center frequency when I start losing signal from the 750.  

Anyways, are shops installing the Comm software version 2.20 even though it's not FAA approved?

I'm not sure this will help or not. My shop told me that if the update doesn't have "TSO" on the update, they consider it an enhancement and the shop charges the consumer for it. If it has the "TSO" designation, it is covered by the extended Garmin warranty.

Not sure this was said to warn me that they would charge me if it wasn't a required update. Since I had been dealing with open squelch issues for a bit, they installed it for free. The radio has been working correctly since.

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[Mooney_Allegro]

I just called my Garmin dealer, and he advised me that if my GTN's were installed via a "Field Approval, then I can legally have Comm Software Version 2.20 installed, but since my GTN's were installed via an STC then I cannot have 2.20 installed because Ver. 2.20 isn't FAA approved yet for STC'd units.  Doesn't make sense to me, but that's what they told me.  

Also, my GTN's break squelch in the hangar no matter if the hangar fluorescent lights are on or off.  Garmin says this is normal for the GTN's.  

[Marauder]

I just called my Garmin dealer, and he advised me that if my GTN's were installed via a "Field Approval, then I can legally have Comm Software Version 2.20 installed, but since my GTN's were installed via an STC then I cannot have 2.20 installed because Ver. 2.20 isn't FAA approved yet for STC'd units.  Doesn't make sense to me, but that's what they told me.  

Also, my GTN's break squelch in the hangar no matter if the hangar fluorescent lights are on or off.  Garmin says this is normal for the GTN's.  

These units are very susceptible to noise. Had an issue with an engine analyzer that caused it to break squelch. I created a thread on the topic.

I don't understand this topic about being field approved versus an STC. I have paperwork that shows mine having an STC.

[Mooney_Allegro]

My avionics shop installed my GTN's via an STC, and did not have the FAA come out and look over the installation and sign it off as a Field Approval.  Apparently if it was "FAA Field Approved", I'd be good to go for the Comm 2.20 update, but I have to suffer with this squelch issue because the FAA hasn't TSO'd the update yet for the STC'd units.  I really wouldn't think most people would get their GTN's Field Approved, but I could be wrong. I'm not well versed on how avionics installs gets approved.  Epps Avionics in Atlanta and Sparkchasers in NC advise me to keep checking back every month to see if the Comm version 2.20 is TSO'd yet and approved.  

[Marauder]

My avionics shop installed my GTN's via an STC, and did not have the FAA come out and look over the installation and sign it off as a Field Approval.  Apparently if it was "FAA Field Approved", I'd be good to go for the Comm 2.20 update, but I have to suffer with this squelch issue because the FAA hasn't TSO'd the update yet for the STC'd units.  I really wouldn't think most people would get their GTN's Field Approved, but I could be wrong. I'm not well versed on how avionics installs gets approved.  Epps Avionics in Atlanta and Sparkchasers in NC advise me to keep checking back every month to see if the Comm version 2.20 is TSO'd yet and approved.  

I'm going to go back and look at my logs. I saw the STC, but I am curious to see if there are FSDO signatures in stuff.

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[flyboy0681]

When I first got the 750 installed it took some trial and error to get the squelch just right. To enter setup mode, press the Home button as the unit is powering up. A menu will be presented from where you should select "Audio" to get to the radio configuration items.

[Mooney_Allegro]

Flyboy, do you remember what your squelch settings ended up at? Mine are both at 75. I experimented with many other settings.

[Marauder]

Flyboy, do you remember what your squelch settings ended up at? Mine are both at 75. I experimented with many other settings.

What else do you have in the plane? My last open squelch issue involved the JPI 900. I ended up with a ferrite clamp on the remote annunciator wire to eliminate it as a source of interference.

You may have something in the plane that is causing the problem. I would begin shutting things off and see if it improves the situation any.

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[flyboy0681]

Flyboy, do you remember what your squelch settings ended up at? Mine are both at 75. I experimented with many other settings.

I really don't recall, it's been a few years.

[Marauder]

Flyboy, do you remember what your squelch settings ended up at? Mine are both at 75. I experimented with many other settings.

The Garmin service note says they should be set to 75. I have a GNC-255B that uses the same Com board as the GTN series. It is set to 50 and works fine. I do notice though I can pick up weaker transmissions easier on the GNC.

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[DXB]

Just as another data point on this- fiddling with the squelch setting on mine made zero difference.  A higher quality usb adapter AND putting a ferrite filter at each end of the lightning cord to my ipad made all the difference- neither alone was enough.  I'm getting the com firmware updated tomorrow to 2.2 for safe measure.

[Mooney_Allegro]

Just an update.....I'm at Lancaster Avionics in PA, and I asked the avionics shop to install Garmin Comm Software update 2.20 because of all the squelch break issues. They advised me that it's illegal to do the upgrade to version 2.20, because there is no airworthiness approval yet.  The new software is TSO'd but not STC'd. This is the 3rd Garmin shop that advised me they can't do it.   I was told that the STC "might" be available in January 2016.  

[Mooney_Allegro]

Marauder,  you mentioned you had the JPI EDM 900. What's the difference between the EDM 900 vs the EDM 930?  It looks to me they do the same thing, but the 930 is much more expensive.     I'm glad your GTN squelch issues are gone!

[Marauder]

Marauder,  you mentioned you had the JPI EDM 900. What's the difference between the EDM 900 vs the EDM 930?  It looks to me they do the same thing, but the 930 is much more expensive.     I'm glad your GTN squelch issues are gone!

It's the form factor. The 900 is the same shape and size of the 830 series but differs in one aspect - it is considered primary and can replace all of your factor gauges.

The 930 is much larger and may have a few features that the 900 doesn't. I looked at the 930 but between cost and real estate required, I opted for the 900.

[Oscar Avalle]

On 11/4/2015 at 0:34 AM, larryb said:

Fluorescent lights in my hanger will break the squelch. Other than that my 650 does not have any of the squelch problems I read about here.

Same in my hangar...

 

[Marauder]

Just an update.....I'm at Lancaster Avionics in PA, and I asked the avionics shop to install Garmin Comm Software update 2.20 because of all the squelch break issues. They advised me that it's illegal to do the upgrade to version 2.20, because there is no airworthiness approval yet.  The new software is TSO'd but not STC'd. This is the 3rd Garmin shop that advised me they can't do it.   I was told that the STC "might" be available in January 2016.  

If I get some time tomorrow I will call my shop. I know the FAA was at my avionics shop a number of times during my upgrade working with them on proper documentation for the shop. I wonder if this could be the difference.

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