This simple radio was found in a Popular Electronics from the 90s. L1 and L2 have 100 turns on a toroidal core and L1 have a socket on the thirtieth turn.
This circuit fires at the touch of a sensor, passing its output from high to low in a time given by...
This circuit was found in a 1967 US publication. In it we have the implementation of a ring...
The strength of an audio signal can be controlled by touching sensors. Keeping the finger in...