Medium impedance stage (CB20563E)

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

Fast adder 2 (CB7056E)
This is another quick adder that we found in an Electronic Design from the 80s. It also applies to...
Simple ohmmeter (CB4152E)
The idea of this circuit is a resistance meter or continuity test with a common microammeter or...
Darlington Automatic Shutdown (CB25614E)
This circuit turns off after a time that depends on C1. The circuit is from an Electronics Now...