On Sun, 15 May 2005 16:08:55 GMT, the renowned
_crusty@ourwonderful.sytes.net wrote:
Quote:
Yup, carbon composition was notoriously unstable. The phenolic casing was not
hermetic and allowed moisture in and out. About the only way they were better
than carbon film was in power surge rating. A 1 watt could take 5 watts of
overload for a split second without more damage than a small change in value.
Carbon films would flash and flameout.
Also, carbon comps have lower self inductance than carbon film, so you'll
sometimes see them still used in RF power circuits. Sometimes with coils wound
about the body, too.
I remember when Ohmite announced years ago they were ceasing production on their
comps and so many engineers wailed 'No!'. Ohmite relented, but did get to raise
prices.
You may be able to sell them on ebay to people who need replacement parts for
their old gear.
|
A client says he switched to them for one application because the
extra noise helped an oscillator start reliably. I'm not sure I
believe it was the factor (the parts he got looked just like film
parts to me, with the telltale bulge of crimped endcaps over a tubular
body) but maybe it got the semiconductor maker ********* out of a
possibly litigious bind by killing enough time for another wafer run
to get out.
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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