Hi Guys,
I'd like to recap an old Denon PMA-920 because the original caps must be over 25 years old. For the PSU caps I'll most likely go for these LINK because of the high ripple current. The original values are 8200uF but I assume 10000uF will be ok?
Could someone have a look at the circuit diagram for me and tell me what the most important caps are? I'd be over the moon if someone could tell me where the decoupling, feedback and coupling caps are.
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I'd like to recap an old Denon PMA-920 because the original caps must be over 25 years old. For the PSU caps I'll most likely go for these LINK because of the high ripple current. The original values are 8200uF but I assume 10000uF will be ok?
Could someone have a look at the circuit diagram for me and tell me what the most important caps are? I'd be over the moon if someone could tell me where the decoupling, feedback and coupling caps are.
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10 000 will be fine. Even higher than that is OK, too.
I would replace all the 3xx numbered electrolytics. Most of them can be replaced with polyester caps with 5 mm lead spacing.
I would replace all the 3xx numbered electrolytics. Most of them can be replaced with polyester caps with 5 mm lead spacing.
So looking at this:
We have C301 and C302 (10uF 25V), C307 and C308 (10uF 50v) and there's a single cap C316 (100uF 10V)
I take it the 10uF caps can be film?
Would a low ESR cap like the Panasonic FM be good for C316?
We have C301 and C302 (10uF 25V), C307 and C308 (10uF 50v) and there's a single cap C316 (100uF 10V)
I take it the 10uF caps can be film?
Would a low ESR cap like the Panasonic FM be good for C316?
No, 304, 312, 314 and 306 can be film. 220 nF and 100 nF. Same for the other channel, obviously. For values above 2.2 uF, film caps are not economical, and for values above 4.7 uF, size is unacceptable. Anything Panasonic or Nichicon will be fine for electrolytics.
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D
Deleted member 24284
In general, is the goal to replace all electrolytic capacitors with either newer electrolytics or film?
I suppose the other parts to replace are those resistors that dissipate a lot of power.
I suppose the other parts to replace are those resistors that dissipate a lot of power.
I was hoping to use film for anything in the direct signal path (coupling caps).
Why, would the value have drifted or something?
D
Deleted member 24284
They are polarized on the schematic so I assume they are electros. Definitely don't put in 10 uF film caps in there. Way too big. Will cause problems.
D
Deleted member 24284
Either use a temperature probe to find the hottest ones, or replace everything that's low resistance.
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