I made a simple PD test circuit which may allow to test PD response up to few 100MHz.
Its not for low noise, only for characterising PD response.
Here is the circuit:
The 2 capacitor values (for bypassing) are kind of arbitrary, just what I found around
(one medium, one small capacity). Could be improved by better RF types (e.g. Mica).
The PD type has no meaning. I put in the Centronic 15-T5 for a start.
The bias can be up to 20V for this diode.
The signal appears across R1. It is small, to make a large bandwidth.
R2 is just for slightly decoupling the signal from the following RF amplifier.
The wire into the RF amplifier is short (~cm). And the amplifier is supposed to have 50 Ohm
input impedance.
I use a mini circuits ZFL 500 here.
power supply for this is 15V.

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