This simple circuit is a continuity test that, in addition to testing resistors, can also test other components. Power is provided by batteries and the LED can be of any color.
This control circuit for incandescent lamps was found in a publication from the 90s. The circuit uses...
The power supply for this circuit must be symmetrical at 12 + 12 V and the load must be 8 ohms. The...
This practical two-transistor linear motor control idea was found in the September 1962 Radio...