The timing steps of this circuit are indicated by a 7-segment display. The circuit was found in documentation from the 90s. The capacitor next to the 555 determines the timing steges.
The transistors of this circuit may be general purpose and the power supply comes from the TTL...
We found this circuit with the CMOS4046 in the August 1994 Electronics Now magazine. The circuit is...
This setting appears with variations at various points on this site. This is from a Motorola...