This circuit was found in an EDN from the 90s. The circuit employs a double 555 and uses the courtesy light switches of the car as sensors.
We found this relaxation oscillator in a 1967 General Electric documentation. The frequency is given...
This circuit was found in the September 1984 issue of Radio Electronics magazine. The circuit has...
Although the BD135 transistor is not specifically for RF applications, some of them can easily...