This circuit was found in a Popular Electronics from the 90s. The circuit has temperature compensation. Coil and capacitors depend on the frequency at which the circuit will be used.
We found this circuit in documentation from the 1980s. The transformer is of the low voltage type...
This circuit generates interval signals controlled by a light sensor. The basic time of the sound...
This simple unijunction circuit is from a Radio Electronics from July 1963. It can be assembled with a...