Synthacon VCF again...
2003-01-13 by Luís Marka
OK, found the bandit. It was a bad 2N2222 in the output stage. Now: Thought
the frequency was not going all the way thru the audio spectrum, so I
replaced the two 2N2222 by two 2N3904s. Now it goes way BEYOND the audio
spectrum, reaching supersonic frequencies with a CV of about 3.5 Volts. How
can I trim the gain of the two transistors, so the CV goes from 0 to 10V? I
don´t know how to calculate the resistors...
All my best, and thanks in advance,
Luis
the frequency was not going all the way thru the audio spectrum, so I
replaced the two 2N2222 by two 2N3904s. Now it goes way BEYOND the audio
spectrum, reaching supersonic frequencies with a CV of about 3.5 Volts. How
can I trim the gain of the two transistors, so the CV goes from 0 to 10V? I
don´t know how to calculate the resistors...
All my best, and thanks in advance,
Luis