Schematic Volt

Flashing neon globes have use in many applications, however their relatively high working voltage precludes their general use where a mains supply is not available.
This simple neon tube flasher circuit enables neon tubes or bulbs to be operated from a low voltage dc supply. The voltage required to ignite the neon tube is obtained by using an ordinary filament transformer (240-6.3Vl in reverse. Battery drain is quite low  being in the region of 1 to 2 milliamps for a nine volt battery. O1 is a unijunction transistor and operates as a relaxation oscillator. its frequency of operation is determined by R2-C1.  The pulses from Q1 are directed to O2 which in tum drives O3 into saturation. The sharp rise in current through the 6.3V winding of the transformer as 03 goes into saturation induces a high voltage in the secondary winding causing the neon to flash.  The diode D1 protects the transistor from high voltage spikes generated when switching currents in the transformer.