Found in Electronics Now, this circuit generates signals for testing like a signal injector. The frequency will be between 20 Hz and 10 kHz with the indicated components.
The circuit shown in the figure is triggered by an input voltage determined by the setting of P1....
This circuit was found in Motorola documentation from 1969. The transistors are from that time. The...
This VCA was found in the July 1988 issue of Radio Electronics magazine. It uses an OTA op amp and...