Hi Colin,
> Anyone built an amplifier using such an rf choke, or tested such a choke on
> a network analyzer?
I haven't heard that idea before, but it is very common to place a
resistor in parallel with a choke, to lower its Q and discourage
self-oscillations. At least in solid state VHF amplifiers, it's more
common to do this, than to use a choke without resistor!
The advantage of using the parallel resistor, instead of distributed
series resistance in the case you mention, is avoiding voltage drop of
the DC supply. RF-wise, the two arrangements work differently over the
spectrum, but both can be used to gain stability at the expense of
efficiency, and for a single, give frequency, a system with series
resistance or parallel resistance can be designed to behave exactly the
same way.
Interesting idea, anyway!
Manfred.
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