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Harman Kardon 870 Varistor replacement

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Good day fellow audiokarma,

I am working on HK 870 and the right bias adjustment can't adjust to 0.0v, I get 0.670v. I checked MV5W varistor and found it defective. The left channel was able to adjust to 0.0v What can be a good substitute for this varistor part. It is a dual diode design. On the schematic it shows 15V

Any consideration???
 
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i can't find data on this double diode part mv5w. The schematic shows double diode. Is there an alternate diode that can work. I replaced a similar dual diode on a Sansui 9090 using 2 diodes.
 
I would guess 1N4151 + 1N4151 would be in-range enough to work. But that's just a guess.
 
I look at another dual diode which is part of current idle circuit. So this is the reference of stv3 or stv4. I checked those other
dual diode and saw a reference for MV12ym on audiokarma. The repair says two 1N4148 diodes will work. So the other dual diode part MV5W can use 1N4151 diodes for repair. These 2 varistors deal with Idle current and DC bias stability. The right channel of HK 870 cannot be adjusted. I will replaced both varistors and also include the left channel also. Hope this will work.
Will give you update once it is done.
 
Hi,
MV5-W is a dual junction stabistor with Vf in the 1.2-1.3V at 10mA of forward current. The 1N4148 and 1N4151 appear to have a bit too high of a forward voltage judging by the graphs in their datasheets. I am not sure this is an issue in this particular circuit. It seems like two 1N4150 in series which match nicely at 10mA ranging from 0.66V to 0.74V. The attached data is from datasheetarchive.
 

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Thanks JoseHH , I ordered 1N4150 diodes and will replaced 2 MV5W diodes on Harman Kardon 870. I also replaced 2 zener diodes on the driver boards also. Just waiting for parts to arrive then I will update. Hope the 1N4150 diodes will work to set the DC offset to this amplifier.
 
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