Found in 1968 Mullard documentation, this circuit uses period components. The transistors are matched pairs and the sensor is an Indian photocell of the time.
Using an operational amplifier with FET, this voltmeter has a high input resistance. The circuit has...
This circuit was found in a Linear Technology documentation from the 90's. The integrated circuits are...
This circuit generates signals controlled by crystal and can generate marks up to 30 MHz of 1 in 1...