R8500 wonkiness

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N9JIG

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I just today unpacked my R8500 from my recent move and got it reinstalled in my new office. Everything else in the shack seems to work fine but the R8500 went wonky. After a minute or two the frequency display started flashing (the characters, not the light). A sharp sound popped out from the speaker that sounded like a power spike or something. It would clink then the squelch would open for a brief moment. It would do this for a few moments then go away.

I tried a CPU reset (hold the MW button down as the radio is turned on) and it seemed to work fine for a few minutes. Somehow this seemed to fix the dial light!

A few minutes later the weird clicking/squelch comes up again. It goes away after a while. This seems to come and go at fairly random times.

This radio has worked fine for the last 5 years or so that I have had it, I have never seen this behavior before.

Could this be a PLL unlock issue? Is this something I can fix without a service monitor/signal generator?
 

N9JIG

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Update

I took off the cover and found that I could replicate the issue by tapping a couple metal cased transistors or IC's contained in a small RF cage on the main unit (the cage near the center of the board).

There are 3 of these round metal devices in the cage and it seemed that their metal cases may have been contacting the metal cage. I tried insulating the inside of the cage and the devices themselves with a paper tape and that seemed to work for a while.

However... After I buttoned up the case and reinstalled the radio the issue resurfaced.

I suspect bad solder joints, perhaps on the underside of the board. That type of repair is beyond my capabilities so I will likely get it serviced.

Are there any better service options rather than Icom itself? I have heard good things about their work and am inclined to send it to them and ask for a general alignment as well.
 

N9JIG

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Weighing the advice I had received from several sources I chose to have Icom Service repair my radio. I exchanged a couple emails with their service manager and arranged to ship it to them. It was received, an estimate provided and approved and then repaired. I received it back last week and it is working well again.

Icom Service was wonderful to work with and I will certainly not hesitate to use them again if needed.
 

N9JIG

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A cracked solder joint on L46 on the main board, cracked cap C252, aligned the reference oscillator and replaced the display lamps.
 

N9JIG

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Looks like I got real lucky. Icom has told a good friend of mine that they no longer support the R8500 for repairs. His radio is doing the same thing mine was so he is looking at 3rd party service depots...
 

woody_46

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This (PLL unlock) is a common problem on the R8500. I had mine serviced by Icom Canada. I'm thinking it's more a problem of overheating. The voltage regulators run hot. Even after the repairs were done my display was flickering kind of like when you drive an audio amp too hard. I installed a 12 volt computer fan (left rear of chassis) to cool it and the display flickering stopped. I've seen other posts recommending a fan too.
 
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