Found in an old publication, this is a transmitter with a spark coil. The high frequency oscillations of the high voltage spark generate the signal thrown at the antenna.
The purpose of this 1967 Philips circuit is to produce a rectangular signal from a sharp pulse....
This circuit allows you to read capacitances on a common analog instrument. It is part of an...
The idea of this circuit is to use an AM radio with headphones to receive sound signals...