Joule Thief

[WilbyInebriated]

Wilby said to remove the cap and the resistor under the cap.  I am not sure why we should do this.  If it puts out 1,500 volts to the screen the way it is, then why should we change it?

Bill

just so it doesn't bite, as you found out. the large output cap stores a burst to fry the bugs, you really don't need it to light a fluoro. it will still put out 1500V without the cap.

@xee
the empty connections on the board marked K1, K2 are for a switch. i have 2 versions, one has a switch and the led is on the topside of board vs. the bottom and one is identical to yours.

[crowclaw]

XEE2:

That is the boards I have from the 2 I purchased.  They exactly match.  I was going to do a photo but, now I don't have to. 

Wilby said to remove the cap and the resistor under the cap.  I am not sure why we should do this.  If it puts out 1,500 volts to the screen the way it is, then why should we change it?

Unless, like the legendary Fuji circuit, a few changes actually make it run like a JT?

I have not had the time to experiment with this board so, let me know what you discover.  As I said, I have 2 of them.  What a deal for like $6.00.

Bill

Hi Bill,

Before anyone removes parts!! I noticed what appears to be a 10M resistor on the extreme left side of the board either near to or underside of the brown cap. This resistor is most likely connected to one of the swatter outputs; if this is the case it's there to further restrict the output current should the device be exposed to human touch!!! SO BE VERY CAREFUL. Those things can pack quite a punch. The design is virtually the same as a JT using a coil with feedback, and most probably has addition caps and diodes to double the output.

[oscar]

.... AV plug , ....

Diodes to used ?

Mk1,
yes, sirmikey1 posted a great photo of an Avramenko plug.
But I want to urgently suggest that you use diode type 1N4148
http://en.wikipedia.org/wiki/1n4148
I think you will find that these diodes lead to very good results at the frequencies and power levels which 'we' work with, due to their capability of fast switching.
You may also want to try to put three diodes in series on each branch, as Dr. Stiffler does for certain applications.

[xee2]

@ WilbyInebriated

My test was with the unmodified board. But when I tried to light a fluorescent tube with the unmodified board the tube would blink because it would discharge the cap each time it lit and then the cap would have to recharge. It should light the tube fine with the cap and resistor removed as you suggested.

EDIT: by any chance, did you happen to measure the capacitance of the capacitor. I do not want to remove mine because I plan on using it in a circuit that needs the cap.

[WilbyInebriated]

Hi Bill,

Before anyone removes parts!! I noticed what appears to be a 10M resistor on the extreme left side of the board either near to or underside of the brown cap. This resistor is most likely connected to one of the swatter outputs; if this is the case it's there to further restrict the output current should the device be exposed to human touch!!! SO BE VERY CAREFUL. Those things can pack quite a punch. The design is virtually the same as a JT using a coil with feedback, and most probably has addition caps and diodes to double the output.

yup, if you remove the 10M but not that cap, and then charge the cap and touch it, it will bite you harder. i tested this some time back when goat? first mentioned these boards.

it's not as bad as licking a plasma globe though...

@xee,
iirc, it was a 0.33uF 600 some volts. i have it somewhere, if you want me to make sure, i can find it.