This 1965 circuit uses a Philips 4068 tube to measure extremely small charges. The circuit has as indicator a micro ammeter and the transistors are of the time.
This power amplifier circuit was marketed in Japan in the 1960s. The transistors are made of...
When excited by a pulse of variable width at the input, this circuit produces a pulse of constant...
The frequency of this circuit, that makes use of a tunnel diode as an active element, depends on...