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Help! King KY-97 Static Problem

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Darinh

Well Known Member
I have a Garmin SL40 as my primary comm and a KY-97 as my backup. The Garmin performs great but has less transmitting power than the KY-97 so I'd like to get it operating properly.

The issue is that the KY-97 has constant "static" when NOT receiving or transmitting... almost like the squelch is not set correctly on that particular radio but both radios feed through a PS Engineering 6000 audio panel and the squelch is set correctly.

Does the KY-97 have its own squelch that can be adjusted independently of the audio panel?

Again, the radio receives and transmits perfectly but when in between communications its nothing but static with 4 quick clicks about once per second. Any ideas what the problem might be?

As a side... the wire harness was professionally built so I don't think that is the problem.
 
BobTurner said:
All modern radios have their own squelch.
Click to expand...

To be a little more specific, the KY-97A is factory preset on the squelch values, but there are two of the four adjustable controls that can be accessed through holes in the top cover plate that affect squelch.

The most forward (nearest the front panel) control potentiometer is called CARRIER SQUELCH, and the one closest to the middle of the unit is called NOISE SQUELCH. The other two controls are MIC GAIN and SIDETONE.

They are factory preset but the IM says they can be adjusted for specific installations if needed.

It's not an easy front panel set-up, you will need to remove the unit, tweak the controls, and re-install. Mark the original positions so you can always return to the factory settings...:)
 
Gil,

Thanks for this information... exactly what I was looking for and hopefully it will fix the issue if it is indeed an squelch issue. I'll keep you posted on what I find.
 
KY-97 Static Problem

Stating the obvious here but there is a squelch control on the volume control knob. Pull the knob out to adjust the squelch and push in for normal ops.
 
jlisler said:
Stating the obvious here but there is a squelch control on the volume control knob. Pull the knob out to adjust the squelch and push in for normal ops.
Click to expand...

No, which is why Bob's comment was a little short...:)

Pulling the VOL knob will switch off the squelch, but it won't adjust the level. That's why it is labeled as TEST on the front panel.

The squelch level is pre-set internally.

ky96A97A.gif
 
I fixed this problem on the same radio by giving the squelch switch (the on/off switch when you pull out the volume control) a shot of contact cleaner. The switch itself was the problem. You need to remove the radio case cover to do this. If that does not work adjust the squelch control as previously discussed.

Carl
 
jlisler said:
Stating the obvious here but there is a squelch control on the volume control knob. Pull the knob out to adjust the squelch and push in for normal ops.
Click to expand...

As Gil stated this is just to test the squelch... has nothing to do with setting the level, unfortunately.

Carl Froehlich said:
I fixed this problem on the same radio by giving the squelch switch (the on/off switch when you pull out the volume control) a shot of contact cleaner. The switch itself was the problem. You need to remove the radio case cover to do this. If that does not work adjust the squelch control as previously discussed.
Click to expand...

Great idea... worth a try for sure before adjusting. Thanks for the tip, Carl.
 
KY97 Static Problem

I stand corrected! However in my case, if the knob is pulled out I have constant static as described in the original post. Pushed in all is well.
 
Well, after getting to the hangar this morning I realized my comm is a KY-197 not a KY-97 which means it doesn't have the squelch potentiometers on the top of the case. I don't have the installation manual or operating manual so I don't know if it has internal squelch adjustment.

I tried the contact cleaner on the test switch without any improvement. Any other ideas now knowing this is a KY-197? The only thing I can figure is a squelch issue as it transmits and receives perfectly clear but static when idle. Checked grounds and they seem to be good.
 
You can easily find manuals on the internet.
I see the squelch test is brought out on the back to pin 10. Take a look, make sure it's not accidentally grounded.
How well do you think you got the contact cleaner into the front panel switch? Without taking it out of the case it's problematic, imho.
 
I have the install manual and it doesn't mention any external adjustments for squelch as does the IM for the KY-97. I removed the radio from the panel, removed the faceplate to access the squelch switch with the contact cleaner.

I will check the wiring diagram and pin 10 to see if it is grounded for some reason. However, I don't think that is my problem as the harness was professionally made, but....even professionals are human. Thanks for the idea.

I'm beginning to think the radio may have a faulty squelch circuit internal to the unit.
 
Since the radio is now out, just reach in from the front and get your ohmmeter probe (may need a small wire and alligator clip) on pin 10, see if it's grounded.
While your radio is apart use your ohmeter to verify that the squelch switch on the volume control does work.
 
Pin 10 is grounded and the switch works fine. Pretty sure its internal with the squelch circuit. I've contacted an avionics tech to see if he can diagnose the problem and possibly fix it. Thanks to all for the tips.
 
Darinh said:
Pin 10 is grounded and the switch works fine. Pretty sure its internal with the squelch circuit. I've contacted an avionics tech to see if he can diagnose the problem and possibly fix it. Thanks to all for the tips.
Click to expand...

I think Pin 10 should not be grounded, it should be left open...
 
Darinh said:
Pin 10 is grounded and the switch works fine. Pretty sure its internal with the squelch circuit. I've contacted an avionics tech to see if he can diagnose the problem and possibly fix it. Thanks to all for the tips.
Click to expand...

There is your problem. Grounding pin 10 defeats the squelch. It should be open. Reach in back and cut that wire.
 
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