We found this 6-tube amplifier in a 1947 publication. It is a Public Address amplifier with excellent performance using triodes on the output.
This UAA170 application circuit was taken from Siemens' own integrated circuits manual from 1976....
We found this circuit in the 1960 Mullard transistor reference manual. The phototransistor can be a...
Found in National Semionductor documentation this circuit combines a tone control with an...