A friend of mine asked me to look at his 5100 series II tuner. One channel is fine, the other channel is lower with just a hint of distortion. I read the other thread on this forum and took the time to reflow the solder joints in the PS section. Same result. I read about the unobtainium ic chips 1001a and 2. I'm not an engineer, but do possess some troubleshooting skills and an oscilloscope. Caps don't show any signs of leakage and I don't want to advise him to do a recap unless someone smarter than me recommended it. I realize that this tuner isn't worth a lot and isn't good enough to throw barrels of money at it. Thanks for adding me to the forum and and advice or suggestions would be appreciated. He said if it's not worth it to fix, he'll split the signal and listen in mono. I did fix his 8000 turntable, which I like a lot. Thanks -Scott
Trouble with a PL 5100 series II
- Thread starter ScottC
- Start date
Listening to mine now.
Mine worked fine when I got it from a pawn shop.
Went ahead and recapped it anyways because I wanted it to be good for decades to come. Didn't find any bad caps.
I did the alignment, and it was spot on.
One thing about it, a single FM antenna feeds it and the earlier PL 5000 S2 tuner that sits above it. The 5100 doesn't have the sensitivity or "warmth" that the 5000 has.
I have better tools now, so I'll look at it's alignment again in the future.
Not a bad tuner, better than many microprocessor controlled tuners I've had in the past.
One thing I will do in the future is remove the wire wraps and posts.
Could be corrosion on the cheap RCA output jacks or the de-emphasis slide switch on the rear.
Remember it's AM and FM, so you'll want to try each to see if it's in one or both sections.
If I found the issue is internal, then feed it a signal and start probing each channel with the scope.
Mine worked fine when I got it from a pawn shop.
Went ahead and recapped it anyways because I wanted it to be good for decades to come. Didn't find any bad caps.
I did the alignment, and it was spot on.
One thing about it, a single FM antenna feeds it and the earlier PL 5000 S2 tuner that sits above it. The 5100 doesn't have the sensitivity or "warmth" that the 5000 has.
I have better tools now, so I'll look at it's alignment again in the future.
Not a bad tuner, better than many microprocessor controlled tuners I've had in the past.
One thing I will do in the future is remove the wire wraps and posts.
Could be corrosion on the cheap RCA output jacks or the de-emphasis slide switch on the rear.
Remember it's AM and FM, so you'll want to try each to see if it's in one or both sections.
If I found the issue is internal, then feed it a signal and start probing each channel with the scope.
Attachments
Thank you for the reply. The distortion and low volume is present on AM and the Rec Level Check. Does that narrow things down? The tone has a thin-ness to it for lack of a better term. This is all on the Left channel.
I suppose it all runs through the 1002A chip, so that could be the culprit.
I suppose it all runs through the 1002A chip, so that could be the culprit.
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Hard to say. The issue could be anywhere in the chain.
Ideally you'd input the signal at the antenna connection with a RF Generator and start probing the signal path from there.
Could be anything from a bad connection, cracked resistor, transistor, cap, etc.
There's also a possibility someone's been in it before and they've turned various trimmers.
Ideally you'd input the signal at the antenna connection with a RF Generator and start probing the signal path from there.
Could be anything from a bad connection, cracked resistor, transistor, cap, etc.
There's also a possibility someone's been in it before and they've turned various trimmers.
