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SA-9800 power resistor substitution

M

MattG9999

New Member
I'm currently working on a Pioneer SA-9800 amp. I found an open power resistor (R76) on board GWH-120. Pioneer part number ACN-047, 0.47 ohm 5W.

Will this part number AC05000004707JAC00 from digikey be a suitable replacement? I will use it in a radial orientation.
 
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think you made a typo as r76 is 2.4k .
r86 i think you mean ..change all 8 is best 4 for each channel . as the others might not be far behind it in their demise ... plus biasing will maybe be better .
 
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petehall347 said:
think you made a typo as r76 is 2.4k .
r86 i think you mean ..change all 4 is best 2 for each channel . as the others might not be far behind it in their demise ... plus biasing will maybe be better .
Click to expand...

OOPS! I meant R79. I cannot adjust bias to 56mV as per service manual. Lowest I can adjust it to is 285mV.
 
still an emitter resistor . if it reads high change the lot . i have in the past changed a bad one then 2 weeks later another one went bad .
if they all read the same you have other issues .
 
Update:
Replaced all 4 power resistors. Bias is now adjustable close to factory specs. I had removed and tested every transistor, diode and resistor to find the fault. I never thought a 5W resistor would be the culprit. They were the last ones to get tested.

Pwr resistor sub.jpg
 
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