This circuit was found in a 1993 Electronics Hobbyst Handbook. The circuit operates in the FM range. The coil has 4 turns of 24 or 26 wire in a coreless form 0.5 cm diameter.
The CMOS 4046 integrated circuit is not very common today, consisting of a very efficient PLL for...
This circuit turns on an old cassette recorder when the telephone rings, thus enabling the...
This circuit can be used in panel signaling with common incandescent lamp. The lamp will flash at a...