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Old April 9th 07, 09:42 PM posted to rec.radio.amateur.boatanchors
Scott Dorsey Scott Dorsey is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 774
Default audio filter circuit chokes/caps

ablebravo wrote:

what is best generic part for this application? ie i need to narrow
down 100's they offer to what i need in some way. was looking at
fastron epoxy mcc/n series. can't find the exact values, either. can
get w/in 20-30 MH. how critical?


Not very, though it will change the filter frequencies by a little bit.
They aren't super sharp, though.

How did the inductors fail, though? They hardly ever do, unless a cap
fails and throws DC on them.

schemo gives two 'filters' (choke/inductor) valued at 175MH and
360MH. also in the package are two mica caps .006mfd and .011mfd.


Miller makes some inductors in that range that Digi-Key stocks. If you
want to be right on, get larger ones than you need and take off winds
until the value is correct. Higher current inductors are easy to do this
with.

the values seem hard to find for micas -- is 'orange dip' substitution
for this ok? i can turn up these micas up on mouser but at $6-25 (!)
each, depending on specs.


Yes, but again, mica caps don't fail easily.

What makes you think these are bad?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."