PIN diodes have reciprocal mixing troubles when a saturation DC current is
absent and the diode is in the conductivity region between the thresold and
complete saturation.
Using PIN diodes as variable resistors or as clampers in RF applications is
really a bad idea. (a PIN diode attenuator was implemented in the TS180
receiver, with terrible IMD consequences)
On the other hand, I don't see big problems when using PIN as pure ON/OFF RF
switches if driven by a proper DC current.
73,
Mauri I4JMY
> Do NOT use PIN diodes, and do not use Schottky devices (they
> breakdown at too low a voltage)!
>
> Also remember these diodes can be the source of IMD and TVI! If
> they are clamping, they are mixing and generating harmonics.
> 73, Tom W8JI
> w8ji@contesting.com
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