This amplifier was found in a tube equipment manual from 1947. The high-fidelity circuit has pentode tubes at the output and a source with transformer.
This small automotive NiCad battery charger uses only passive components and has the number of...
This different circuit uses a relay as an oscillator, whose frequency is determined by C1, and to...
In this circuit we show how to modulate the pulses produced by a 555 in frequency. The circuit can be...