This circuit is from an American publication of the 80's. It makes use of components of the time. However, the circuit is the basis for a modern shield application since the input is TTL.
This sensitive circuit detects the live pole of a power grid or outlet. The circuit makes use of a high...
This FET stage circuit was obtained from old American documentation but can be applied to any FET....
Found in old American documentation, this circuit can use crystals between 27.5 and 33 MHz...