>
>>>Resistors don't create resonances
>>>
>>I agree, Gerard.
>
>How can you agree, Rich, when even you admit there is no such thing as a
>"non-inductive" resistor?
>
To create a resonance one needs capacitance (the anode-C) and inductance
( principally the leads between the anode and the tune-C). Resistors can
be in the current path of a L-C resonant circuit, however, resistors do
not create resonance.
>> In this case, the suppressor resistor is connected in
>>series with an existing resonant circuit -- i.e., the anode-C, the anode
>>lead's total L plus the net X of the Tune-C, plus the chassis-L between
>>the Tune-C gnd and the grid or screen gnd. . For a 3-500Z, typical
>>values are 5pF and c. 300nH. Typical resonances are 100 - 150 MHz.
>
>Yes, you are correct here. I think what I hear you saying is that the
>inductance of the resistor is small enough that it really doesn't have
>that much effect on the overal resonance of the anode circuit.
sort of
>It causes
>a slight shift, but not a huge one as Peter had suggested. Do I read you
>correct?
>
The suppressor resistor needs to have little L so that the
higher-resonance will be well above the resonance through the (more
inductive) suppressor inductor. Since the suppressor R has some
intrinsic L (hopefully under a dozen or so nH) - the suppressor slightly
decreases the resonant frequency.
- later, Jon
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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