Volume expander amplifier (T364E)

This circuit was found in the 1961 RCA tube manual. The circuit includes a power supply stage.

Optical Shield TTL - II (CB1324E)
The drive levels of this shield are opposite to the previous one. The photo-transistor can be of...
5 W Darlington Amplifier (CB6177E)
We found this circuit in a 1969 General Electric documentation. The circuit uses transistors of the...
Parallel Port Isolating Buffer (CB4858E)
In the original 2000, this circuit was designed to interface the parallel port with external...