This circuit is from an 80's technical newsletter. The circuit can use any general purpose transistor and its power supply can be changed with a resistive divider to use a single 9V battery.
This circuit was obtained from an American 1980s documentation. The frequency depends on the...
New Low-Power PIC24 “GA7” Microcontroller Family Now Available CHANDLER, Ariz., Dec. 12, 2016 — The...
We find this circuit in an English 80's documentation. The circuit can be made with more modern...