I recently picked up a KA-5700 knowing it didn't work. The owner wasn't really sure what was wrong but the price was right and it looks pretty nice from the outside.
I pulled the cover and noticed both 5A fuses are pulled. That can't be good.
Pulled the main filter caps and they measure 6487uF and 6088uF. Probably need to replaced with fresh ones.
Tested the PS diodes (Dm17-Dm20) and they seem good. With the main PS fuses pulled, I'm getting 61vac from the transformer.
Using a DBT, added 5A fuses and tested no voltage on the speaker outputs.
I'm only getting 1.2v at the power supply Dm17. Schematic says I should get 40.5v. Pulled PS jumpers to the phono section with no change. Something is pulling down the PS.
I can follow Spenser's guide and order new caps.
Anything I should check before I just order caps?
I'll try to get some pics uploaded.
Thanks.
I pulled the cover and noticed both 5A fuses are pulled. That can't be good.
Pulled the main filter caps and they measure 6487uF and 6088uF. Probably need to replaced with fresh ones.
Tested the PS diodes (Dm17-Dm20) and they seem good. With the main PS fuses pulled, I'm getting 61vac from the transformer.
Using a DBT, added 5A fuses and tested no voltage on the speaker outputs.
I'm only getting 1.2v at the power supply Dm17. Schematic says I should get 40.5v. Pulled PS jumpers to the phono section with no change. Something is pulling down the PS.
I can follow Spenser's guide and order new caps.
Anything I should check before I just order caps?
I'll try to get some pics uploaded.
Thanks.
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