Step 4: Troubleshooting
Then I decided to get a bigger CFL and I build it exactly like the first circuit. It didn't work. I was disappointed. I thought that the CFL electronics were shot.
But when I reconnected the fluorescent tube to the four wires, the CFL worked again. I realized that this type of CFL circuit needed to "sense" the filaments in order to operate. Remember, I was only using the outer wires and leaving the two inner wires alone.
So I put a resistor across the outer wire and the inner wire. The circuit worked! But within seconds the resistor was in flames.
So I decided to use a capacitor in place of resistor. The capacitor allows AC currents but blocks DC while a resistor allow both AC and DC currents to flow through it. Also a capacitor does not heat up because it provides a low resistance path for AC currents.
The capacitor worked great! The arcs produced were very big and thick.
So in summary there two things that can go wrong:
1. You wired it wrong, either on the CFL side or the flyback side.
2. The CFL electronics needs to sense the filament and you can use a capacitor as a substitute.
Use a high voltage rated capacitor. Mine was 400V and I got it from another CFL circuit.
While troubleshooting, be very careful, you are dealing with very high voltages and high currents.
When soldering, disconnect the circuit from the power outlet.