CFL Fluorescent ballast help!!

[Clarkdale44]

Hello

I want reuse my old cfl tubes, i found a simple circuit that can drive them again but there are two components which i am unable to find, do anyone think i can replace 47nf/ x2 275 vac capacitor and 2.2uf 250vac with something else. Or if you have a more simple cfl ballast circuit where i don't need a transformer or winding any cores.

Regards!
This is the circuit i have been trying to make.

 

[KeepItSimpleStupid]

X and Y capacitors are used for line applications. They fail nicely. I did find the 0.047 uf caps at digikey. The 2.2 uf here: **broken link removed**

The higher value caps will probably be found in companies that make speaker crossovers and parts.

 

[tcmtech]

I think I see a fatal flaw with the circuit. It will be putting a DC current across the lamp which will give it a rather short remaining life before it burns the filaments out.

 

[MrAl]

Hi,

Yes, running the lamp from a DC source causes metallic migration of the element which causes a blackening of the tube.
Modern designs always use AC with a cap in series to perfectly balance any offset DC.

Also, a voltage doubler may not provide enough starting voltage depending on the tube length.

 

[audioguru]

.......before it burns the filaments out.

One filament is shorted and the other filament uses only one wire so it also has no current. Then the filaments will not burn out.

Yesterday I saw many boxes full of brand new but the old version of 4' fluorescent light tubes on the curb. I still use them in the light above my workbench and I already have a half-full box of them. All stores have already converted to the new power-saving ones.
I have used many cfl bulbs but only my first one used an inductor for its ballast. All the others came with an electronic ballast that have a tiny little high frequency transformer. The high voltage electrolytic capacitor usually fails first.