Phase 2 inverter (CB22233E)

This circuit was found in an American publication from the 50's. The transistors are made of germanium and the power supply is dual.

Balanced amplifier (CB7396E)
This circuit was found in Sgnetics documentation from the 80's. The circuit also has loudness...
High Voltage Regulator (CB16990E)
This regulator circuit is for high voltage inputs making its initial reduction so that a common...
3 kW Control (CB21382E)
This heating element control with up to 3 kW was obtained from an old American documentation. SCRs...