Found in a 90s Electronics Engineering, this circuit makes use of components of the time. The critical component is the microwave sensor diode.
This interesting AC / AC converter is only indicated for resistive loads and was obtained in a...
This 1967 Raytheon circuit uses a Raystor, an optical coupler with a lamp and an LDR. The circuit...
This electronic voltmeter circuit was found in a documentation from the 50's. The sensitivity is...