Yamaha A-720 Potmeter question

Addict1337

New Member
I've decided to repair my A-720 witch only plays sound on one side (If I up the volume the other side starts tho).

After a bit of fiddling around I noticed that the balance potmeter is definitely broken/working poorly.
So I decided to replace all of the potmeters since i'm opening the unit up anyway.
However I haven't been able to find any potmeters that will fit, or that have an equal amount of 'K'.

I wrote these values down, witch are the potmeters that i'll replace:
62 2P S-40K
0-100K
61 8F 250kMN
300K
60K 622P (volumeknob)

I'm fairly new to amplifiers, not to soldering tho.

Maybe someone on this forum can help me out with this one :)
 
Potentiometer---:thumbsup: Welcome to AK... Plan B " start shopping for a donor candidate.":idea:
 
Really :( ?
I would really like to have new ones since this amp is (as you probably know) is really old one, and I guess most of them aren't working properly anymore.
 
PM Clinic-audio...Patrice might be able to help you out.
 
According to the service manual
VR201 --->HS312120 or HS411920 yamaha part #'s (balance)
VR203 --->HS320700 or HS420340 yamaha part #'s (volume)
 
Thank you guys very much for the replies so far.
I've dropped Clinic audio a message, and have been able to find a website who has 35mm potentiometers with the right amount of "k" for at least the 250k potmeter.

Are there parts I can use on this website? Is this the right one, since they have a lot of kinds of potentiometers there:

http://www.futurlec.com/PotRot.shtml

I don't really care if I have to order each individual potmeter from different websites, as long as I get them :)
 
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Hello Addict1337

Sorry but where are you ?

Please send me picture of the defective one . Value is not enough for me to find the right one .
 
I've been fiddling around a bit more, and noticed something.
When I bridge the Balance knob for the right channel, the sound starts playing again! :)

I guess i'll just solder them together, who needs balance anyway :)

Also I cleaned out the remaining potentiometers, and all is working well now.

Thanks very much for helping everybody.
 
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I've been to an Audio expert today.
Het cleaned out 1 of the potentiometers, the other one was done for so I need a replacement for that one.
For now I bridged the connections of this potentiometer on the circuitboard so I can still listen to music.

18fbl2.jpg


2ptyz5x.jpg


Thanks in Advance :)

(This is how it's looks now without the potentiometer :( )
2v8pb4k.jpg
 
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