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Jeff Liebermann Jeff Liebermann is offline
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Default Bulging caps by design?

On Sat, 1 Jun 2019 19:33:08 -0400, Ralph Mowery
wrote:

In article ,
says...

The TV is 11 years old. Maybe it's time to replace the bulging caps.
If you can make them fit, I suggest a higher voltage rating.


Higher voltage is ok, but higher temperature is probably better. I
think 105 deg C is the higher ones now.


Yep. 105C is better.

In computahs, I've been replacing bulging electrolytics with aluminum
polymer caps. They're substantially more expensive, but that's not an
issue for simple recapping of a motherboard, where the quantities of
caps used are small. Most of the better motherboards already use
polymer caps instead of electrolytics, especially near the rather warm
CPU. I have yet to replace a polymer capacitor, while electrolytic
replacements are epidemic.

Here's the Mouser selection of 470uf 16v polymer caps:
https://www.mouser.com/Passive-Components/Capacitors/Aluminum-Electrolytic-Capacitors/Aluminum-Organic-Polymer-Capacitors/_/N-bmaie?P=1z0wrk5Z1z0z7l5Z1yx4aw3
Unfortunately, 16v is as high a voltage that can be commonly found.
Mouser only has one cap rated at 25v:
https://www.mouser.com/ProductDetail/KEMET/A750MS477M1EAAE015?qs=M6jHmRuQorU%252BFZ0HJe9oAQ%3 D%3D

No clue what's happening in the TV business. My guess(tm) is that
they continue to use the cheapest parts possible on the assumption
that using expensive parts, which might outlast the other overheating
parts in the TV, is bad design economics.

"Bad Electrolytic Capacitor Teardown"
https://www.youtube.com/watch?v=tKphKWAkeSU (4:32)



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