>
>>>Any problem using 500 volt ceramic disc caps for the larger values and
>>>silver mica for the smaller ones.
>
>>The disc ceramics should be NPO or N750 types, Steve
>
> Why NPO? With Q=2 Bandwidth (-3db) of the tuned circuit
>is F/Q = .5*F or 50%
The Q-method is Eimac's simplified version, which considers only the
reactance of C1. The effective Q is higher. Ceramic bypass-type
capacitors (includes 1000pF and 500pF, 5kV doorknob capacitors) have
horrible temp. coefficients. Tuned circuits require something better.
- later, Bill
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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