Re: nonpolarized caps

On Mon, 10 Mar 2025 17:33:59 +0100, Gerhard Hoffmann <dk4xp@arcor.de>
wrote:

Am 10.03.25 um 16:30 schrieb john larkin:
>

I asked for experience and advice, not snark.

>
I have used these WIMA capacitors (10uF version) in the input
of an ultra low noise FET amplifier. Absolutely no complaints.
>
Gerhard
>
>

Yeah, film is ideal if I can make them fit. As noted, the board will
be crazy dense. My production and test people might make funny faces
if I suspend giant axial power resistors and caps above surface-mount
parts. How about a baby board on hinges?

The design is actually an 8-channel programmable dummy load that
simulates both resistance and inductance. But it occurred to me that,
having eight isolated bipolar-output class-D amps, we could futz with
the output filtering and get an 8-channel power supply from the same
PCB layout.

I've wondered if the bipolar aluminum caps work right after being DC
biased one way for a long time.

There is one dirty trick of putting two alum caps in series opposing,
with a diode across each to prevent back-bias. That's crazy nonlinear
but might be OK as a power supply filter.

Maybe jamming film caps on the board is best.