Inverter Amplifier (CB6431E)

This high input impedance circuit was found in a Popular Electronics of the 90s. The circuit supports modern operational.

Transistor Voltmeter (CB1412E )
The purpose of this circuit is to increase the sensitivity of a common multimeter in its voltage...
Elementary Radio (CB15084E)
This is the modern version of the Galena radio in which the detector is a germanium diode (which can...
Nanoammeter (CB12009E)
This circuit allows the measurement of very weak currents indicated on an analog instrument or...