Found in a 1965 Motorola documentation, this circuit uses a neon lamp as a trigger element. The SCR admits equivalents and the lamp must be incandescent.
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...