This SCR timer was found in an old English documentation. The SCR can be the TUIC106 and modern equivalent transistors like the BC557 for TR1 and BC547 for the others.
This circuit is from 1989 documentation. It uses the TDA2002 as a modulator and the unusual power...
This configuration is suggested by Mullard (Philips) in an old manual of 555 integrated circuits....
The figure shows how to use a CMOS amplifier as a crystal-controlled oscillator. The circuit is...