Joule Lamp

[Djoko]

Hi all,

I just beginer in this forum. I made this lamp also last week. I am using 1" x 9" pvc pipe. 0.2 mm x 600 turn on sec, 1.5 mm x 43 turn on primary, tip 3005 and running on 12 V batt. The 45 watt cfl get very bright at 1.65 amp. The output voltage extremly high ( almost 1500 v). The problem is the transistor getting very hot. 
Here is my short vid.
https://www.youtube.com/watch?v=S9DggKjswh8

[NickZ]

  Hello Lynxsteam and all:
   I'm still working on my 3.0 Ringer replication, using the smaller 3 inch ferrite rod.
   My transistors are still getting too hot on 12 volts though.
  It's very late at night here, I'll post some more tomorrow.
   The voltage on the circuit is about 10 volts, which is about what it can handle at the moment using the smaller transistors. I haven't had luck with the MJE 3055 (TIP 31), yet.
  I've got a 3inch coil from a crt monitor yoke. that I'm going to wind for this purpose, as I can't get the big expensive ferrite rod like LS uses.
   
           NickZ

[TinselKoala]

Very nice, showing lighting the low voltage LED and the much higher voltage NE-2 with the same output, and your fingers acting as part of the circuit. The ferrite helps by allowing you to make your coils physically smaller, but the basic idea is vrswr: voltage rise through standing wave resonance. Air core coils need to be larger to operate at the same frequencies but have the potential to give higher voltages and currents because there is no core to saturate.
These results are very impressive due to the low voltage input. Keep up the good work!

[Lynxsteam]

Here's a schematic of the circuit I use for more power.  3055 Transistors can take a lot of power but if you want to push CFLs or fluorescents you will probably push plastic cased transistors beyond their 1 amp limit.  2N2222 transistors work fine for LED bulbs but are pushed hard by CFLs.
Connect two transistors in mirror image, but use a 1 Ohm resistor across the bases to even out any slight difference.  You can gang up several transistors this way.
This kind of defeats the purpose of simplicity, but if you really want to light more wattage this will help.
I still have my most reliable success using LEDs.  They take half the power of CFL's and incandescents are just silly off this DC converter.
Connecting bulb from HV coil and collector help keep the transistor in its power range.

I'll post some photos of my big LJL using the two transistors.

[rxpc]

Hi Lynxsteam,

  what kind of LED bulbs are you using? I think I can get as many as 40 primary winds on my little toilet roll setup, right now I have 2 layers of 250 winds of 30 awg wire secondary and 16 primary turns of 14 awg wire. I can light a 14 watt modded CFL light now close to 70% brightness and using 458ma. After adding a switching diode across the base/emitter, the CFL is brighter and....so far...seems to have eliminated my kick start issues.

I tried placing a ferrite rod inside the roll, but the CFL gets dimmer, I was using the rod to help kick start the circuit. The 2N3055 transistor still gets pretty hot, even with the diode and heatsink.

Thanks!