This is certainly a low-cost 20W/40W fluorescent lamp inverter circuit project. Even so the maximum effective would be to make use of a 40 watt tube (or two 20 watt tubes in series). It is a circuit you may put collectively from junk box parts or assemble from a kit. It certainly is quite easy to construct and no need printed circuit board. The transformer is hand-wound on a ferrite rod (from an old transistor radio) and the winding wire could be salvaged from an old transformer. We’re intentionally maintaining bills down to confirm how cheaply it could be put together.

20W/40W Fluorescent Lamp Inverter Schematic


Dependant upon your stock of components, the cost could vary from $3.00 to about $15.00 and in case the wires from the transformer are soldered to the ends of the tube(s), you are able to make a free-standing light that can be set-up in the garden to light up a dark place without having the worry of operating 240v wiring. The cost of powering the circuit is about 22 watts and this will make the same light output as a 60 watt globe.

Using a regular fluoro operating on the 240v mains, a ballast (or choke) is required in series with the tube to limit the current after the tube has “struck”. This ballast dissipates about 10-20 watts for a 20 watt tube and lowers the effectiveness of this circuit. In case the ballast is replaced with an electronic circuit and high-frequency transformer, the losses are lower than 5 watts. In addition, if we tend not to drive the tube as tough as the 240v type we are able to get even better effectiveness.

Parts List:

1 – 2R2 1/4watt (for testing)
1 – 47R 1/4watt
1 – 180R 1watt
1 – 47k
1 – 100k mini rim pot
1 – 100ngreencap
1 – 100u 16v electrolytic
1 – BC338 transistor
1 – TIP 3055 transistor
1 – on/off switch
1 – 12mm bolt and nut for transistor
1 – heat-sink 5cm x 10cm
1 – ferrite rod 10mm dia x 8m long
1 – 30m winding wire .28mm dia
1 – 4m winding wire .61 mm dia (wire diameters are NOT critical)
1 – insulation tape either sticky tape or masking tape
1 – interlayer insulation – paper

PCB Kit Design:

 
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