Thermostatic relay (CB21285E)

We found this circuit in an old QST magazine. The circuit is powered according to the thermostatic relay used.

Guitar Level and Solo Switch (CB17046E)
This circuit was found in a 1997 documentation but uses absolutely common components today. The...
Power control with reset (CB8146E)
This circuit was found in a 1967 General Electric manual. It has a circuit that discharges the...
1 Hz Time Base 2 (CB24205E)
We found this time base circuit in a timer project from the August 1972 Radio Electronics...