An LC tank drives a transistor to generate pulses in a 12V lamp. Switch down to charge LC tank, switch back up to oscillate, down to recharge. In the up position, the switch branch uses a voltage divider to add about 635 mV to the base of the transistor, increasing its sensitivity to LC oscillations as they dampen. 1K resistor to transistor base isolates transistor from larger power swings if you want to play with different values of L and C.
