General vinyl talk here.

Moderators: lazyben, static14, texasvinyl

User avatar
By inksb
#117011
Sorry for dropping this in the Vinyl section but it's one of the most visited areas and I was hoping to get a little help on an issue I'm having with my receiver.

I had to retire my workhorse last year that I had for a very long time. I am currently using an old Yamaha that I had in my garage that some one was throwing out because they bought a new one. It sounds great but I have an issue with the Input Switch. Any time I switch between inputs I get drop outs in left or right channel(usually left), some times the left channel is gone completely. If I wiggle the switch left or right and sometimes up and down I can get the channel to come back. I rarely have issues if I just keep it on my Phono input but when I switch to tape I always have to mess with it and the same goes for when I switch it back. I'm currently at work so I can't post photos. I've hit it with some Deoxit D5 but that doesn't seem to work. Any suggestions?


Here is a similar receiver I found, it's not exact as I don't know the model but input is on the bottom right before you get to the big volume knob.
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User avatar
By static14
#117013
Sounds like oxidation .

Buy a can of deoxit. Open it up and try to get a clean shot at the input pot. Shoot some deoxit in it (there should be small openings on it)

Work the pot through all the inputs many, many times, back and forth through the range. Like a hundred times. If this fixes it you’re golden. It if helps, get back in there and try to find other openings in the pot/switch to get the deoxit inside and work the knob back and forth again a bunch of times.
User avatar
By tim28212
#117014
@static gave some good advice. If you're not familiar with Deoxit and how to use it you can find several videos on youtube on how to use it to clean pots.
User avatar
By inksb
#117017
static14 wrote: Wed Apr 10, 2019 8:48 pm Work the pot through all the inputs many, many times, back and forth through the range. Like a hundred times. If this fixes it you’re golden. It if helps, get back in there and try to find other openings in the pot/switch to get the deoxit inside and work the knob back and forth again a bunch of times.
I have done Deoxit before but I have not worked it 100 times. I will give that a go and see where it takes me.
User avatar
By static14
#117019
inksb wrote: Thu Apr 11, 2019 1:37 am
static14 wrote: Wed Apr 10, 2019 8:48 pm Work the pot through all the inputs many, many times, back and forth through the range. Like a hundred times. If this fixes it you’re golden. It if helps, get back in there and try to find other openings in the pot/switch to get the deoxit inside and work the knob back and forth again a bunch of times.
I have done Deoxit before but I have not worked it 100 times. I will give that a go and see where it takes me.
You really have to saturate the pot and work it a good bit.
User avatar
By inksb
#117020
I definitely stayed on the cautious side of spraying in previous attempts, was worried about excess. I'll just give it a good coat, work it a lot, then reapply and work it some more.
User avatar
By maxlevel
#119258
@inksb did you solve this? I took apart a technics amp not so long ago, the pots are often not fixed in. They just push back on. You can remove them with pliers if you’re careful, get right into the metal underneath with the dexoit. The larger pots often need a socket ratchet 14mm to separate them from the black plastic front.
User avatar
By inksb
#119260
Not really. If I spray it with deoxit, move the switch back and forth 50+ times the problem goes away for a bit but usually a few weeks go by and it comes back. It's currently in it's "reapplication" phase, I switch from my tape to phono input last night put a record on and walked out of the room, only to realize about a minute later that nothing was playing because the amp had completely cut out. I moved the switch back and forth a few times and the sound came back. It's minor but annoying.

Do you have some pics or a video detailing what you are talking about? I think I understand but also don't want to blindly do it and damage it as I can't afford a new one right now.
User avatar
By maxlevel
#119263
inksb wrote:Not really. If I spray it with deoxit, move the switch back and forth 50+ times the problem goes away for a bit but usually a few weeks go by and it comes back. It's currently in it's "reapplication" phase, I switch from my tape to phono input last night put a record on and walked out of the room, only to realize about a minute later that nothing was playing because the amp had completely cut out. I moved the switch back and forth a few times and the sound came back. It's minor but annoying.

Do you have some pics or a video detailing what you are talking about? I think I understand but also don't want to blindly do it and damage it as I can't afford a new one right now.
So not all of the front facing pots are fixed in place. The larger pots are held in with a locking sleeve so you’ll need a ratchet and socket to remove those. But the smaller ones are often just held in by virtue of being tight fit to the control shaft. In this image the white pots are removable and red is locked. The plastic part is just a matter of careful removal. Once you have access you can apply spray better, or get a better look at the issue

If deoxit isn’t helping then old fashioned elbow grease and some wire brushes where the carbonisation is will sort it, you’ll have to get in there and remove the buildup by hand
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