This circuit was found in an American documentation from the 80's. The components are from that time. It provides a variable output of 18 to 30 V with a current of 200 mA.
We find this ultra-simple transmitter circuit that is nothing more than a very short range RF...
The circuit shown is from National Semiconductor's Linear Applications Handbook published in 1994....
This configuration that appears several times with variations on this site is from old American...