AC to DC converter outputting constant voltage instead of proportional output

Thread Starter

nadirEatsKoukies

Joined Dec 11, 2020
17
Hi guys,

I've been trying to design a conductivity meter based on the tutorial in this link , The oscillator works perfectly in simulation but the second part of the circuit always outputs a constant ~10.5V DC instead of it being proportional to the resistance of the solution (I replaced the conductive solution by a resistor in simulation), no matter what value resistance I put.

Here are the circuit and simulation
1611156176450.png
1611156207808.png
 
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