Found in the March 1989 issue of Radio Electronics magazine, this circuit is used to test printer and other cables. The indication is made by LEDs.
If you have a disused old computer, the type that still has a parallel port, you can use it in...
Using earphone for listening, this receiver has only one germanium transistor. The circuit is from...
This oscillator can generate signals up to a few megahertz depending on the crystal used. Actually...