Test circuit with bridge (CB22530E)

This bridge-biased transistor test circuit measures gain in the range 0 to 300. Circuit is from Radio Electronics June 1952.

Intercom Amplifier (CB6304E)
This circuit was found in a Ferranti documentation from 1969. The transistors are common types of...
Powerful Amplifier (CB18826E)
This powerful amplifier with 2N3055 transistors at the output provides a few tens of watts rms on a...
Precision Current to Period Converter (CB15773E)
This interesting circuit is suggested by National Semiconductor and is based on an LH0062...