Joule Thief

[Mk1]

@jeanna

Ok i did not know you had one, that is good. Ok connect the + and - go to the multimeter. you connect pickup coil under test one ac connector , and the other to diode.Usually the side on witch you get more voltage is the + side.

But you can also , just use the bridge 4 leg thigny  , and connect coil to ac ends and read voltage at the + and -.

[WilbyInebriated]

@ Wilby:

Thanks.  How did you know this?  Were these marked or did you have some way to measure it?  I don't think the ones I ordered had any specs on this, which would have been nice.  Do we know what the leds are putting out?  I have a lot of stuff to learn and do in a short time it seems.  I am kind of hoping you will tell me there is a simple way to measure this.  Thanks again.

Bill

to be truthful i have no fancy lab equipment. i took leds of known wavelengths placed them in a lightproof box (as light proof as i could make it) which was then placed over the solar cell. the output/response of the solar cell is what brought me to this conclusion. as i said, far from lab conditions, but it seems to be a reasonable conclusion. 880nm is infrared, so you might want to augment your visible light ones with those. careful with your eyes.

[jeanna]

I just tried my 20 turn pick up that I used for the 30 LED array in the bridge rectifier.

This shows 16Volts DC WOW

It also shows 24Volts AC  ??

MK, is this an anomaly? or is this being wasted? and the reason to add a diode to the pickup coil?

thank you,

jeanna

[Mk1]

@jeanna

Yes it can happen , but if you have only one coil on the configuration ,its really not a problem . If you have more than one try to check all possible connection.

The single diode is for test only.

Edit: Diodes drops the voltage a bit.

[Pirate88179]

@jeanna

Yes it can happen , but if you have only one coil on the configuration ,its really not a problem . If you have more than one try to check all possible connection.

The single diode is for test only.

Edit: Diodes drops the voltage a bit.

Drops the voltage????  We can't have that now.... ha ha.   Do they also drop the power or does that remain the same?  I am planning on using the diodes off of that cfl I took apart as per your suggestion.  I have a lot of catching up to do.

Bill