This simple circuit for the 3 to 30 MHz range was found in the Electronics Experimenter Handbook Special Projects of 1983. The coils consist of 10 and 50 turns of 32 wire on a 1 M x ½ W resistor.
We found this circuit in the June 1991 issue of Radio Electronics magazine. The integrated circuit is...
This polarity test or indicator indicates the polarity of a power line by LEDs. The circuit is...
This circuit is from Motorola's 1990 Linear Databook. The transistors allow equivalents and the...