This simple circuit was found in a Japanese magazine in 1967. The circuit is listening on a headset and the coil is 50 + 50 turns of wire 28 or thinner on a ferrite rod.
In the figure we have the way to use a shift register to divide the frequency of a signal by 9....
We found this circuit in Texas Instruments documentation from 1986. The circuit produces a...
This interesting transformerless class B output stage was found in a patent registration published in...