Hi Peter,
> As far as having the resistors inside the inductor is concerned, many
> people got away with it for a long time. But it doesn't appear to be the
> brightest thing to do, does it, putting a lossy conductor tightly coupled
> to the magnetic field, such as to try to increase the RF current in the
> resistor?
Worse yet, virtually all carbon and metal resistors are wound with a
spiral. They are inductive. Not only does that decrease the
effectiveness of the suppressor, the spiral can couple magnetically
to the winding and really decrease current through the resistor at
VHF, just what you don't want.
One cure is to park the resistor outside the suppressor coil, and
series tune it with a small mica cap. That not only increases
current through the resistor at VHF, it decreases resistor current at
HF.
Since inexpensive non-inductive carbon resistors are getting nearly
impossible to find, the capacitor in series with a resistor might
become more common.
73, Tom W8JI
w8ji@contesting.com
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