Found in a publication by Gernsback from 1960, this circuit uses germanium transistors of the time and commercial coils. It can be changed to operate with modern transistors and other wavebands.
This relay shield was found in the October 1993 Electronics Now magazine. The circuit is powered by...
In the figure we have the basic configuration of a regulator for 12 V x 1 A suggested by Motorola in...
This circuit can be used as part of a Vox project or as an input shield for a microcontroller that...