This interesting sensor for RF signals was found in an article in the June 1989 Radio Electronics magazine. It is a field strength meter with an LED bargraph indicator.
This circuit was found in the April 1983 issue of Radio Electronics magazine. Its purpose is to...
Evidently, this is a project that still needs some improvements. For example, the ignition can be...
This very low voltage regulator for 3 V input (2 batteries) was obtained in a documentation from...