This alarm circuit triggers when S1 opens. The circuit from a January 1975 Radio Electronics magazine can be used with interrupt sensors connected in series.
This field strength meter is intended for the VHF range, above 100MHz. The lowest voltage or...
We found this circuit in an English publication in 1976. The circuit is based on the use of a...
This antenna tuner was found in a 1995 publication in the 1993 Electronics Hobbyists Handbook. The coil...