High Gain Amplifier (T137E)

This high gain amplifier stage uses a pentode valve. The circuit is from documentation of the 50's. The drained current is a few tens of milampères.

Code Practice TTL Oscillator (CB4188E)
This simple Morse Code oscillator was found in a 1980s American documentation. The power supply...
25 W Modulator (CB4162E)
We found this circuit in a 1980s publication for amateur radio. It consists of an audio amplifier...
Protected Power Supply (CB4667E)
The maximum current of this power supply is 2 A and the output voltage can be set between 6 and 24 V. The...