The Flasher

You’ve probably seen those flashing lights on level crossings – or on emergency service vehicles. Guess what makes them work?
That’s right: a circuit just like this one!
You can make a number of flashing light circuits, simply by varying a few components.

You will need these components
Resistors:
One 390 ohms (orange – white – brown)
Two 10k ohms (brown – black – orange)
Capacitors:
Two 100uF 10 volt electrolytic type
Diodes:
One protection diode (1N4002 or similar)
Two light emitting diodes (LEDs)
Transistors:
Two NPN type DS548 or similar small signal type
Miscellaneous:
One battery clip
Five lengths of tinned copper wire
One 3cm length insulated hook-up wire
17 self-tapping screws with washers
Baseboard and project overlay No. 5