This circuit is from an ancient American documentation. The transistors are of the time and the circuit uses a special sensor to detect the trigger point to produce spark plugs.
April 2017 - Mouser Electronics has the bq25890H integrated circuit consisting of a single 5 A...
This circuit causes an LED to flash at intervals determined by C1 and R2 and for a duration given...
This is a typical common collector amplifier step configuration. The transistor can be used...