Can you help me finding a replacement of these capasitors ? I can’t figure out if it’s for AC or DC.
is it ok to pick higher voltage or not?
PHOTO-2025-01-17-16-57-43 copy.tiff (9.0 MB)
PHOTO-2025-01-17-16-57-43 copy.tiff (9.0 MB)
its from REALİSTİC SA-700 AMP
Welcome to the technical forum. Unfortunately I am not finding anything to offer on the website.
Can you figure out is it ac or dc ?
No. Not with the picture provided. Sorry. Though just because I can’t verify it, we do have a whole community watching these posts. So I would give it time and someone else might find what I missed.
C852 and C853
Thank you for the additional information. We will see if anyone will be able to help on this one.
Hello @cemkadirpulan,
These filter capacitors are attached from the transformer’s secondary to the amplifier’s DC common. They will see the full secondary voltage. IMO, they are a bit oversized for voltage. However, we must account for voltage spikes.
Keep the original value.
May I recommend an axial film capacitor selected from this listing.
Best wishes,
Aaron
P.S. That is a clean very good-looking amplifier.
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Hello cemkadirpulan,
From looking at the schematic, it appears the capacitor connect right to the output of the power transformer, so it should be AC current. Maybe one of the engineers can reply also.
Wow a classic 70s Technics receiver, in 2025 dollars it would cost over $3000.00US.
Those capacitors where often used to eliminate the click in the audio output when the power is switched. Most often they would be simple cheap 1kV ceramic caps but in this high end product they obviously went with much more expensive film caps for better suppression.
Any of the film units in the list @APDahlen provided should work very well.
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Thank you, @PaulHutch.
I am impressed at the condition of @cemkadirpulan receiver.
thank you so much i really appreciated.i will check out the list thanks for your help.
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sorry its not Technics but i think its the humble verision from Radioschack realistic series also fully built in japan.
I’m stuck between affordable general use and expensive EMI and RFI suppression. Is it worth it? does it affect the sound quality?
In truth, @cemkadirpulan,
I don’t know, as this is a subjective question.
As @PaulHutch pointed out, these caps are installed on the AC line to remove the clicks from the incoming power line such as when a load elsewhere in your house was turned on.
For what it’s worth, the capacitors are not always installed in this position. In fact, when I looked for the SA-700 schematic, the older units did not appear to have the capacitors.
Sincerely,
Aaron
P.S. Have you read the David Sax’s book “The revenge of Analog”? It’s a good read as he explores the range of human thought and actions in relation to technology. Who would have thought, vinyl records are more popular today than they were in the 1980s.
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Thank you, @PaulHutch.
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In agreement with above that they likely would have minimal to no effect on audio quality, but are there for “pop” mitigation on power up.
If I recall correctly, at least some of the Realistic audio products were private labeled Harman Kardon designs, which are generally considered to be pretty decent products. I have no idea if yours is one of those or not. I do recall that a college buddy had a Realistic receiver that sounded really great!
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thank you.i will go with the general purpose with low ESR one.