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Transponder Failed Check

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pilot28906

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Hello all, looking for some input. My Garmin GTX327 transponder failed the two year check for frequency being too low. Garmin can repair for $809 or exchange for an overhauled one for $971. I purchased mine about 6 years ago on VAF for $500. I have the uAvionics Echo (w/enconder) and the GRT Safe-Fly 2020 WAAS GPS for ADSB In/Out. My thinking is the overhauled might be better assuming Garmin has went through it and overhauled it back to some standard. What do you guys think or any different options?

Thanks
John
 
pilot28906 said:
Hello all, looking for some input. My Garmin GTX327 transponder failed the two year check for frequency being too low. Garmin can repair for $809 or exchange for an overhauled one for $971. I purchased mine about 6 years ago on VAF for $500. I have the uAvionics Echo (w/enconder) and the GRT Safe-Fly 2020 WAAS GPS for ADSB In/Out. My thinking is the overhauled might be better assuming Garmin has went through it and overhauled it back to some standard. What do you guys think or any different options?

Thanks
John
Click to expand...
Rumor is that there are a few people left who can still adjust the frequency on these that may be able to do it for you. I just bought a yellow tagged unit off eBay when this happened to me last year.
 
pilot28906 said:
Hello all, looking for some input. My Garmin GTX327 transponder failed the two year check for frequency being too low. Garmin can repair for $809 or exchange for an overhauled one for $971. I purchased mine about 6 years ago on VAF for $500. I have the uAvionics Echo (w/enconder) and the GRT Safe-Fly 2020 WAAS GPS for ADSB In/Out. My thinking is the overhauled might be better assuming Garmin has went through it and overhauled it back to some standard. What do you guys think or any different options?

Thanks
John
Click to expand...
Easy adjustment if you’d rather send to me. 1 hr bench time labor charge.
Pretty common issue on the 327.
 
Walt said:
Easy adjustment if you’d rather send to me. 1 hr bench time labor charge.
Pretty common issue on the 327.
Click to expand...
Good on you Walt.
Mine barely passed by .002, whatever that means….. but good to know you still can do it for a reasonable cost.
 
That 327 is a very good unit. You've got a good adsb in and out so let Garmin fix their legacy unit, slap it back in and go fly
EDIT: let walt do it
 
Walt said:
Easy adjustment if you’d rather send to me. 1 hr bench time labor charge.
Pretty common issue on the 327.
Click to expand...

Walt, Had the same problem, sent to Garmin though $$$$. If the 327 was off by 4Mh and power was down to 50W, is that repairable by you.
 
Flyingleap said:
Walt, Had the same problem, sent to Garmin though $$$$. If the 327 was off by 4Mh and power was down to 50W, is that repairable by you.
Click to expand...
When the freq drifts off the output will drop a little as the output is tuned for 1090, but I doubt it would drop that much.
From my experience the power output is usually good, or none.
Was that 50-watt measurement from a bench test or radiated?
 
Walt said:
When the freq drifts off the output will drop a little as the output is tuned for 1090, but I doubt it would drop that much.
From my experience the power output is usually good, or none.
Was that 50-watt measurement from a bench test or radiated?
Click to expand...
Radiated, about two feet....
 
Walt said:
A bench check is the only way to determine if it’s the unit or something in the airplane. It’s the first thing I do if something doesn’t check out.
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You're right, I should have, at least given the 327 transponder, who just failed it do a bench check. My thinking has been if it is Garmin, it is not field repairable.
 
In the absence of a bench setup, my go to is always the antenna. A DC test for ground does not reflect impedance at frequency. I remove the antenna if necessary, clean up the ground plane contact, visually check the coax and connector. Reassemble and recheck. A high impedance connection to the ground plane can cause the freq to be off. Although, Walt’s offer seems like a cost effective approach to know that you have a good radio, and given his indication that freq drift is a known problem for the radio.
 
When my Kitfox was completed in 2013 I flew it to Walt for the initial transponder check. Lo and behold, the frequency was off! I was devastated but within an hour he had it back within spec and it has passed with no issues ever since. I highly recommend his services!

Henry
 
I want to give an update on my transponder. After sending the transponder to Walt and getting it back I finally got it reinstalled and had the transponder check done again yesterday. The transponder passed with no problems! I want to thank Walt and his shop for great service at a great price. Walt you saved me hundreds of dollars. I gave the radio guy who checked the transponder your shops info. Thanks again for great service.
 
pilot28906 said:
I want to give an update on my transponder. After sending the transponder to Walt and getting it back I finally got it reinstalled and had the transponder check done again yesterday. The transponder passed with no problems! I want to thank Walt and his shop for great service at a great price. Walt you saved me hundreds of dollars. I gave the radio guy who checked the transponder your shops info. Thanks again for great service.
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Second that. I just got mine back as well, 4 MHz low. Very quick turn around
 
Walt said:
When the freq drifts off the output will drop a little as the output is tuned for 1090, but I doubt it would drop that much.
From my experience the power output is usually good, or none.
Was that 50-watt measurement from a bench test or radiated?
Click to expand...
Reviving old thread, ATC cannot see my GTX327 transponder and a bench check shows power at only 50W, based on this thread that seems to suggest the unit is toast and not field adjustable, is that correct?
Figs
 
uk_figs said:
Reviving old thread, ATC cannot see my GTX327 transponder and a bench check shows power at only 50W, based on this thread that seems to suggest the unit is toast and not field adjustable, is that correct?
Figs
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Don’t usually see low power, usually works or it doesn’t. Was the freq correct?
TheNewGuy said:
Walt, are you still offering this service and if so, any chance you can fix a 320A?
Click to expand...
Yes still doing it, 320 is basically the same as the 327. Send me an email if you want to send it in for repair.
 
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