Found in a 73 magazine for radio amateurs of the 1980s, this circuit uses a dual-gate MOSFET. This component is not currently common.
This is an amplifier stage with a typical germanium transistor from the 60's to the 70's. The...
Also suitable for use as a noisy alarm, this Morse Code or telegraph practice oscillator was found...
This circuit was found in ancient American documentation. Diodes are general-purpose types. |...