This 1967 modeling circuit mimics the whistle of a locomotive. The steam-shrieking wheezing is set in a 2k2 potentiometer.
Originally created to feed the filaments of a 12AX7 as an audio preamplifier to eliminate the...
This circuit has a scale of 0 to 2.56 V, but it can be changed by changing the values of the...
I found this circuit in an old documentation from 1982. The circuit can be assembled with the...