We found this circuit in the Electronics Experimenter Handbook magazine from 1993. L1 has 2 = 2 turns of 28 or 30 wire in the shape of 0.5 cm without core. The range reaches a few tens of meters.
Found in a Popular Electronics from the 90s, this circuit triggers an indicator when these lights...
This common circuit using a multivibrator causes two lamps to alternately flash at a frequency and active...
This 80s signal follower makes use of an audio amplifier of the era. The circuit can be adapted to...