This circuit was found in documentation from the 1980s. It is powered by the audio signal that must be cut. Transformers are the critical components and transistors are 2N2222.
A little more complex than the previous one, and can now be called a shield, this circuit can be...
Although not using transformers, this amplifier may have difficulty mounting if the original...
This zero-crossing switch circuit triggers an SCR when the input voltage goes through zero. The...