This circuit is from Delco Radio found in a 1968’s documentation. The transistors are of the time and are not given information about the driver transformer. Note the high supply voltage.
According to the author of this project, from a documentation on espionage from the 1980s, this...
This circuit suggested by Siemens can provide time intervals for triggering values that are given...
This circuit generates a good-intensity 1 kHz rectangular signal. The circuit is from Electronics Now...