Medium impedance stage (CB20563E)

We found this circuit in an English publication from 1963. The circuit uses germanium transistors of the time.

Limit Comparator LM339 (CB19793E)
This circuit is valid for other comparators of the same series. In this case, a lamp is excited, but...
LM741 10 kHz Fourth Order Low Pass Filter (CB25933E)
This filter was found in the May 1989 issue of Radio Electronics magazine. The components can be...
20 W amplifier (CB9906E)
The load on this amplifier is 8-ohm. We found the circuit in a 1972 Motorola amplifier manual. The...