We found this small FM transmitter in an Australian publication from 1991. The 3-transistor circuit has a range on the order of 400 meters.
This circuit uses common transistors for a fault indicator that turns on an LED and provides an...
The sensor of this circuit is a common silicon diode and it directly drives a small cooler with a...
This circuit found in a documentation of the 90s, uses integrated common at the time, but...