With this passive circuit it is possible to modulated in amplitude a low intensity RF signal. The circuit is from old American documentation and uses a germanium diode as its main component.
This audio stage can be used in siren circuits, sound effects and others to excite a few watts...
In the figure we have the way to make the connection of voltage regulators in series to obtain a...
This circuit was found in a 1967 US documentation. The FET is general purpose and the 6V zener....