Temperature control (CB21365E)

This circuit was found in an old GE SCR manual. The SCR must be in accordance with the relay and transformer as well.

Telephone recording circuit (CB21270E)
Found in an American documentation, this circuit shows how an interface should be made for...
DC Triggered AC Switch Using Triac (CB13294E)
We found this circuit in an old American documentation from the 70s. The Triac can be of any type...
Heterodyne Frequency Meter (CB18295E)
The operating principle of this circuit, from a 1956 publication, is simple to understand. The...