The flash rate depends on R2 and C2, which can be altered to change the circuit performance.
Current drain, and therefore the lamp brightness, depends on the characteristics of the transformer and lamp. Current drain is between 100 and 400 mA.
Any small transformer rated for 5 to 12 V and currents between 100 and 500 mA can be used in this project. Radio Shack 27 3-1385 is suitable.
A schematic diagram of the Fluorescent Lamp Flasher is given in Fig. 1.
The transformer is the same as used in other projects using the 4093 shown in this section
Transistor Q1 must be mounted on a heatsink.
The fluorescent lamp is rated from 7 to 40 W, and even ones that no longer function at power line voltage can be used.
Better performance is achieved by adjusting the values of capacitor C1 and resistor R1. These components can be altered in a wide range of values.
You can also replace Q1 by any power FET to obtain better performance.
IC1 - 4093 CMOS integrated circuit
Q1 - TIP120 or equivalent NPN Darling‘ton power transistor
F1- 1 A fuse and holder
X1 - 7 to 40 W fluorescent lamp
T1 - 12.6 V, 300 mA secondary, 117 Vac primary transformer (see text)
R1 - 47,000 ohm, 1/4 W, 5% resistor
R2 - 2,200,000 ohm, 1/4 W, 5% resistor
R3 - 2,200 ohm, 1/4 W, 5% resistor
C1 - 0.22 µF ceramic or metal film capacitor
C2 - 0.47 11F ceramic or metal film capacitor
C3 - 100 µF, 16 WVDC electrolytic capacitor
