This bank of switches can be programmed in a variety of ways for logic experiments. The circuit is from August 1986 Radio Electronics magazine.
Mouser Electronics is announcing the availability of the new voltage regulators with low dropout...
This circuit aims to use a low current reed-switch, switch or sensor to control a high current load....
The LM386 is an audio amplifier, but it can be used as a good oscillator with a positive feedback...