This interesting sensor for RF signals was found in an article in the June 1989 Radio Electronics magazine. It is a field strength meter with an LED bargraph indicator.
Suggested by General Electric in 1965 documentation this circuit is intended for the 120 Vac...
This very high impedance circuit was found in documentation from the 1990s. The configuration can...
Found in the 1969 neon lamp documentation, using neon lamps this circuit provides 18 V regulated...