Voltage Level Detector (CB22135E)

We found this circuit in an English documentation from the 80's. Transistors are general-purpose types.

Amplified megaphone (CB23703E)
This is an improvement on the previous circuit with a preamplification stage. The circuit is from...
Instrumentation Amplifier (CB782E)
This circuit was found in a Texas Instruments handbook about operational amplifier. It has a very...
1000 V pulses (CB6930E)
This circuit was found in an American publication from 1965. The circuit uses components from that...