The circuit in the figure uses two operational amplifiers: an LM101A and an LM102. Diodes admit equivalents and resistors do not have to be accurate. The power supply must be symmetrical.
This circuit, from the 90's, is intended for operation with vinyl record players of the time, as...
Using a zener diode it is possible to change the linearity of the scale of an analog instrument by...
Found in American documentation from the 1980s, this circuit prolongs the ringing of a doorbell or chime...