High Power Alarm (CB20475E)

We found this circuit in a Popular Electronics from the 90's. The circuit uses three SCRs to trigger the loads.

Balanced Modulator with Transistors (CB4237E)
Found in a 1980s telecommunications documentation, this balanced modulator circuit uses...
Plant soil heater (CB7964E)
This circuit was found in a 90’s 303 Circuits. The components are from the period and the heating...
Micro MW Receiver (CB16436E)
This simple receiver that works with only 1.5 V, was found in a 1987 documentation. The integrated...