This circuit for light modulated in frequency (FM) operating at 50 kHz was found in a 90’s Electronics Now. The circuit has an active filter. Modern equivalent transistors can be used.
This circuit can be used at the same time as a preamplifier and voice by activating a relay when...
This 1000: 1 voltage-controlled filter circuit was found in an Electronics Today International in a 1980s...
This transmitter emits signals in the FM range, reaching a few meters away. The modulation...