[Lowfer] Interesting finding

[Bill Ashlock]

Status report (relative to capacitor selection for Medfer TX loop):

I found some polystyrene caps in the range of 120 to 240pf and bundled 5 of 
them together to reach the needed ~800pf . The Q was not quite as good as 
the 3 paralleled COG ceramics. I found a spec sheet for the COG (NPO) 
ceramics and the Q is listed at 4000! Also checked the specs on mica and 
polystyrene and I'm reading ~2000 for both. Looks like I need to read up on 
the ceramics! I'm not sure when they entered the high Q capacitor arena but 
my spec sheet is about 5 years old. I've seen them also called monolithic 
ceramics and I've used them in many in low power Lowfer circuits - basically 
any circuit that I previously used  mica but didn't have the space. They're 
certainly inexpensive and very small. Anyone out there know any details on 
these? Temp stability is excellent.

I think the voltage rating on these is only 50vdc and I'm running over 100v 
RMS at the moment on a life test. It's not exactly a catastrophic failure 
should they not hold up at .1w. <G>  Next I try them at 185k.

Bill

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