This timer, like the previous circuits, uses a currently uncommon integrated circuit. The time is given by capacitor C1 and R2 which has the range of values indicated in the diagram.
Texas Instruments ESD122 Electrostatic Discharge Diodes (ESD) can be ordered from Mouser...
This alternating flashing system uses two-color LEDs. The circuit is from a Radio Electronics...
I found this simple circuit from an English magazine from 1984. The circuit can be easily...