Using LM3909 integrated circuits, this circuit was found in an American documentation from the 90's. The frequencies can be changed by changing the capacitors.
This short-range experimental transmitter emits a signal with many harmonics, without modulation. It can...
The LM380 is not a modern component and in some cases not easy to find. But if you have one you...
This is the analog part of the previous circuit with the pressure sensor for the altimeter. The...