Tell me about -- GTN Squelch Issues...

[Marauder]

Ok... a little while back I remember reading a few posts about squelch breaking through on your GTN units. I hadn't seen the issue and I thought I was immune to it, Well that changed today. I took a trip to upstate New York to take my mother-in-law home after a visit. Okay before this goes too far, she made it home fine, although I was tempted a few times to figure out that you really could open a Mooney door in flight. And for those of you wondering, her broom was in the shop for its annual, so she had to suffer through riding home in a Mooney.

 

Back to the topic. There were a number of approach and center controller frequencies that worked me. Some of the frequencies were fine, but others I was hearing nothing but a loud squelch noise coming through. Most of the time when the controller spoke it was understandable but I did need to listen through the squelch. On a few other frequencies, everything was clear and no evidence of an open squelch. I tried to make sense of the frequencies. I don't think I had issues in the 13X bands but did on the 12X ones. 

 

What have others experienced? Makes me sick to think is that I paid a lot for this expensive box and I am subject to these issues...

[rbridges]

I thought I saw another thread about it, but I see that you actually posted in it.

 

http://mooneyspace.com/topic/11899-gtn-750-650-squelch-fuel-flow/

 

my recommendation would be to call garmin and see if they've had any firmware updates since your unit was installed.

[Marauder]

I thought I saw another thread about it, but I see that you actually posted in it.

 

http://mooneyspace.com/topic/11899-gtn-750-650-squelch-fuel-flow/

 

my recommendation would be to call garmin and see if they've had any firmware updates since your unit was installed.

 

Yep, I posted on that thread for issues I had with range and the screen flicker. I never had an issue with the squelch -- until tonight. I know range and squelch are tied together somehow. Wonder if this is the root of my problem.

[NotarPilot]

We have a GTN 650 at work that has some squelch issues as well. I heard the problem was Garmin rushed these units out too fast before working out all the bugs. Second, if you leave the active frequency on 124.0 MHz or higher the squelch problem goes away. Probably not what you wanted to hear but I'm just sharing what I've been told. Can you verify if that fix works with yours? We only have one GTN unit.

[Marauder]

We have a GTN 650 at work that has some squelch issues as well. I heard the problem was Garmin rushed these units out too fast before working out all the bugs. Second, if you leave the active frequency on 124.0 MHz or higher the squelch problem goes away. Probably not what you wanted to hear but I'm just sharing what I've been told. Can you verify if that fix works with yours? We only have one GTN unit.

 

I will post all of the frequencies I had issues with as well as those I didn't. Left the log with the plane. I do know that I had issues with 123.7, 124.1 and a few others. 126.25 was okay as was unicom 122.7 and 123.05. I think the Center freqs in the 13X range were okay.

[MB65E]

I've had issues with 128.2, and a few others in that range. It's a pulsating tone that progresses until you transmit, then it starts over again. If I touch the tip of the antenna while this pulsating tone is going on in the hangar, it goes away. Also, it was really bad when I had the power wires for the ANR next to the comm cords. Since then I have disconnected the 12v ANR source. This was a documented problem that Garmin was going to fix with Software updates. I think there is a build up of something in the Comm coax. Very frustrating to have a $10k+ box that sound worse than my kids headphones.

-Matt

[Marauder]

I've had issues with 128.2, and a few others in that range. It's a pulsating tone that progresses until you transmit, then it starts over again. If I touch the tip of the antenna while this pulsating tone is going on in the hangar, it goes away. Also, it was really bad when I had the power wires for the ANR next to the comm cords. Since then I have disconnected the 12v ANR source. This was a documented problem that Garmin was going to fix with Software updates. I think there is a build up of something in the Comm coax. Very frustrating to have a $10k+ box that sound worse than my kids headphones.

-Matt

It really irritated me to see this issue come up. As I reported in the other thread, I was having some range issues and the flickering screen but no squelch opening issues. The only things that has changed was that I installed the JPI 900. I am wondering if there is some connection with electronic interference from stuff onboard.

The squelch issue I am seeing is like if push the volume button and open the squelch. When I pushed it, I could hear no difference between the squelch being on or off. Unfortunately, I was in and out of IMC or I would have played with shutting off things to see if it made a difference.

I know there were firmware updates to address this and I think I am on version 5.0 of the main firmware and the associated 3 something for the Com firmware.

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[MB65E]

I think it's 5.3 now. Check and see If there is a new source of power near the headsets cables/harness.

Ugg,

Matt

[Marauder]

I think it's 5.3 now. Check and see If there is a new source of power near the headsets cables/harness.

Ugg,

Matt

Thanks for the suggestion. Hopefully will find some time late this week to try to narrow this down.

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[Marauder]

I was reading on another thread someone talking about a strange beeping sound through their headsets. One of the responders asked about iPad interference.

I normally shut off my cell phone but I didn't check my wife's and mother-in-law's phone and iPad. If these were all on, do you think this could cause the squelch to open?

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[ArtVandelay]

I get squelch breaks when charging with cigarette charger, if I unplug it goes away.

[RocketAviator]

Chris,

As you may recall I had 3 GTN 750's changed out.  My 650 has been solid as a rock since day one.

2 of the 3 750 had squelch breaks issues.  I tried every update and the default Squelch threshold adjustment from Factory 0 to the highest setting which I don't recall what it was.  We tried the Garmin suggested setting of 75, that did help but did not solve the issue.

I got very angry with Garmin and had some very heated conversations with my avionics shop and Garmin directly.  The first swap was a bit more than a challenge as I had to prove it was their unit... had all the coax replaced with the high$ special coax they say is required and all kinds of things I spent a small fortune on!!!!  Then I finally videoed the event multiple times and took the Avionics shop on a ride to show him!  He was always a supporter just to set the record straight.  He then got with Garmin and after 2 more units I have not had a single issue with this 750.  Never an issue with the 650. 

 

teejayevans is correct it can as I have seen 3 GTN give squelch breaks when a device is plugged into the cigarette lighter.  I had the issue myself when using a cheap unit.  Got one from Dominic that owns Mygoflight.com that I ran into at Oshkosh.  By the way they participate as a sponsor and provide give always for the Caravan, but i digress!

 

Bottom line some devices plugged in can and do cause some issues but never have with my GTN650.... Solid as a rock!

 

I fully believe Garmin does know they have an issue, just wont talk about it or admit it.  That is what irritated me most.  I realize all companies have issues with products from time to time, I know the world of certified aircraft components are supposed to be as immune to those type of things as possible but issues do and will occur.  That is tolerable to me, not admitting they have a problem is inexcusable to me!

 

Wish you the best and hope you don't have to go through what I went through.  

 

PS Garmin was having issues with the weather and traffic being displayed on the G500, so in advance of the purchase I required and received in writing when I purchased that the unit would provide weather and traffic on the G500 and if it didnt for any reason Garmin would provide it to me at no charge when it came out.  They agreed and when this last upgrade came along they honored the agreement!  Even included the larger Supplemental Data SD card required to operate with the update.

[Marauder]

Lacee -- thanks for the information. I am flying it over to the shop on Monday to have them look it over.

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[rbridges]

hope you get it figured out.  I know that has to be extremely frustrating.  it may be justifiable in a 30 year old Narco radio, but not in a state of the art GPS nav/com.

[Marauder]

We have a GTN 650 at work that has some squelch issues as well. I heard the problem was Garmin rushed these units out too fast before working out all the bugs. Second, if you leave the active frequency on 124.0 MHz or higher the squelch problem goes away. Probably not what you wanted to hear but I'm just sharing what I've been told. Can you verify if that fix works with yours? We only have one GTN unit.

I've had issues with 128.2, and a few others in that range. It's a pulsating tone that progresses until you transmit, then it starts over again. If I touch the tip of the antenna while this pulsating tone is going on in the hangar, it goes away. Also, it was really bad when I had the power wires for the ANR next to the comm cords. Since then I have disconnected the 12v ANR source. This was a documented problem that Garmin was going to fix with Software updates. I think there is a build up of something in the Comm coax. Very frustrating to have a $10k+ box that sound worse than my kids headphones.

-Matt

I kept track of all the frequencies that worked and didn't. Here they are:

Problem frequencies: 124.1, 123.7, 125.15, 124.35 (all had open squelch sounds that ATC needed to transmit through and were barely readable)

Working frequencies: 134.8, 133.35, 127.47, 123.05, 126.25 (were fine with normal clarity).

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[Marauder]

hope you get it figured out. I know that has to be extremely frustrating. it may be justifiable in a 30 year old Narco radio, but not in a state of the art GPS nav/com.

Thanks. I'm really getting me mad at the situation. Not only because my EXPENSIVE Garmin (hear that Peter Garmin?) is messing up but I didn't mention that my "repaired" 22 year old Narco also decided to act up on the trip.

The issue with the Narco was scary. When the Garmin started breaking squelch, I switched over to the Narco. I was being worked by Philly when I hear something like an electrical snap through the headset. I didn't think anything about it but the normally busy Philly frequency was quiet. I switched over to the noisy Garmin and realized the Narco was dead. I pulled the squelch on the Narco and heard nothing. A few minutes later it came back but every time I heard the "snap", it was gone again.

Needless to say, I read up the lost com procedures...

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[RocketAviator]

So sorry to hear. I have a set if Collins I took out of my Saratoga I'll send you if that will help.

Do u have a hand held WITH a connection to your ship antenna?

If not may be a good idea!

I have one never had to use it but I check it a couple times a year just to make sure and it works very well hooked to ships antenna

[Marauder]

So sorry to hear. I have a set if Collins I took out of my Saratoga I'll send you if that will help.

Do u have a hand held WITH a connection to your ship antenna?

If not may be a good idea!

I have one never had to use it but I check it a couple times a year just to make sure and it works very well hooked to ships antenna

Thanks Lacee. I will see what the shop thinks is going on. Funny you mention Collins. I have a buddy here with a 77J that has a few Collins spares he has picked up over the years for spares. He doesn't have the racks, just the radios and he will slide one in when one dies and then pick up another on eBay. He told me to go this route because apparently these do show up regularly and are solid radios.

I would like confidence in both of my radios but at this point will settle for one healthy one.

I do have a jack for a portable. It was for the KX-99 that I had until it died. I bought a Vertex and have a glass mount antenna for it. Never tried it in flight. Maybe it is time to figure out if the King jack can be used with it.

I will keep you posted. Thanks for the offer.

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[Av8]

I can add to squelch and other. Noise issues when charging on the cigarette plug. I have a dual USB plug typically charging stratus and iPad or iPhone. Issues go away when unplug fron cig lighter.

Otherwise gun 650 has been solid.

[Marauder]

I can add to squelch and other. Noise issues when charging on the cigarette plug. I have a dual USB plug typically charging stratus and iPad or iPhone. Issues go away when unplug fron cig lighter.

Otherwise gun 650 has been solid.

 

The shop called today and told me they loaded me up with the current firmware. Waiting to see what it does. 

[RocketAviator]

The shop called today and told me they loaded me up with the current firmware. Waiting to see what it does.

Do u have the G500 with VS and Alt preselects

Those functions changed on my panel I like the old functions much better....

[Marauder]

Do u have the G500 with VS and Alt preselects

Those functions changed on my panel I like the old functions much better....

Nope. Me Cheap Bast$&d, went with Aspen.

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[Marauder]

Just a quick update. With the current firmware for the COM (2.2), the situation is no better (hear that Peter Garmin -- I can't). Really getting frustrated with this situation. Anyone who is dealing with the 650 squelch issues, could you drop me a PM and provide me some details if you were able to get it resolved. I need to know what to say to the avionics shop and Garmin (hear that Peter Garmin -- I can't).

[Marauder]

As a side note, my 22 year old Narco seems to have decide to join the Garmin conspiracy. I have another thread on this that I will resurrect. What would you put in for your second radio?

[RocketAviator]

Just a quick update. With the current firmware for the COM (2.2), the situation is no better (hear that Peter Garmin -- I can't). Really getting frustrated with this situation. Anyone who is dealing with the 650 squelch issues, could you drop me a PM and provide me some details if you were able to get it resolved. I need to know what to say to the avionics shop and Garmin (hear that Peter Garmin -- I can't).

I think you know all about my 750 issues, the 650 solid as a rock since new.

I can get my new 750 to break squelch on some frequenceys in the 122 range if I am using one perticular cigerate lighter USB power adapter.

If I remove the USB cable from the adapter (which I have multiple permanant... well plugged in always for my (IPad, Clarity SV, Phone) the squelch clears up. Again only with one of the cheap 12 vdc to usb power adaptrers the 2 better quality units I have seem to not have any problems.

Hope any of this helps in any way!

Keep us posted, but if your other radio is having issues would seem to me there might be something else that could be causing radio frequency interferance. Just a wild guess on my part.