Hi all! I'm trying to simulate a very simple and wellknown circuit in synthesizers which takes a 1 Volt/Octave input and outputs an exponential current (which usually goes to something like an OTA). However, I can't seem to get this to work at all. I've tried it with the little toy simulator on Falted and also with LTSpice. No dice. What am I missing here?
I'm running a simplified version of the expo converter part of this:
https://www.birthofasynth.com/Thomas_Henry/pdf/VCO1/vco1_schem1.pdf
And I get this (not what I'm expecting, which is an exponential current increase with increasing control voltage at the input):
I'm running a simplified version of the expo converter part of this:
https://www.birthofasynth.com/Thomas_Henry/pdf/VCO1/vco1_schem1.pdf
And I get this (not what I'm expecting, which is an exponential current increase with increasing control voltage at the input):
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