Voltmeter VTVM (T131E)

We find this circuit in documentation on tubes of the 1940s. The circuit applies to other triodes and the instrument is a milliammeter of 0 to 1 mA.

Polarity Converter (CB5289E)
This circuit was found in a 1976 NASA manual, making use of components of the time. The transistor...
Wind charger (CB6056E)
This Linear Technology circuit charges a battery from the energy produced by a wind generator that can...
10 A NC Relay Shield (CB6015E)
This 10 A solid state relay was found in a 1980s documentation. It can work as a shield and...