TARDIS with pulsing light

Inspired by the great model from countspatula I decided that the TARDIS needed a pulsing light on top as well as the internal windows. I didn't want to use an arduino or other microprocessor just to achieve this so went old-school with a 555 timer. Most of countspatula's model is retained here with the addition of a new battery holder to take two slide switches from radioshack (275-0007) and a micro breadboard to hold the additional electronics. You can adjust the pulse duration by varying the c