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.
The circuit shown in Figure bellow generates frequencies of 50 Hz, 100 Hz, and 200 Hz. The circuit uses a...
This circuit rejects frequencies around 1 kHz and can be adjusted using C1. Equivalent operational...
From stereo inputs, this circuit generates a modulated and multiplexed signal to be transmitted in the FM...