Joule Thief

[jeanna]

@jadaro,
The times I have seen a real looking sine wave, have been in very odd places.
Usually a led is involved and sometimes a cap plus led are involved together.
I have not been able to make any predictions about getting this sort of thing, though.

the last 2 times I saw a sine wave were
1- at the other side of a transformer on the multiple secondaries circuit, and
2- when I made the conical secondary and measured the output across the secondary with 3 leds in series already in place.

I wish you luck in your search!

jeanna

[jeanna]

ty that has really helped clear alot up for me i got to 5 winds and damn got to remeber not to look stirght on at the bloody led so do you thin tuning the collecter and base winds will drop the amps used

Yes, usually that gives the best output for the least cost.

I see you have learned how blinding the leds can be!
I was doing A LOT of this last year and I just stuck a resistor into the circuit (breadboard) at the pos of the battery to keep from blinding myself. Later I would remove it.
Lidmotor uses a rheostat at that spot and when he is finished, he has a variable light.
This is a cool thing, because that really saves the battery.
You can have the light half on then when you want to read or see better, you can turn it up.

jeanna

[dasimpson]

or i been doing the blinding thing with lights for years more so when you change battery and look to see if it has improved then always say to my self i wont do that again but a simpson moment doh

Yes, usually that gives the best output for the least cost.

I see you have learned how blinding the leds can be!
I was doing A LOT of this last year and I just stuck a resistor into the circuit (breadboard) at the pos of the battery to keep from blinding myself. Later I would remove it.
Lidmotor uses a rheostat at that spot and when he is finished, he has a variable light.
This is a cool thing, because that really saves the battery.
You can have the light half on then when you want to read or see better, you can A.

jeanna

[dasimpson]

now this i do love i hope they still do them and hope i can find one online

@ all
I drove into town today and bought a little device to try and get the best output out of my torrds.
What I got was a "Resistance Wheel", or Resistance Substitution Wheel". It cost me $19.95 Australian dollars, would be about $10 American.


This device has inside it all the resistors from 5 ohm to 1Meg ohm, I clip the red and black clips where the 1K resistor goes at the base of the transistor and after applying power, I turn the wheel until I get the best possible setting, against the best output of the torid.

Look at the scale, the pointers arrow will point to the resistor which is the one putting out the best voltage.

I believe there is a Capacitor wheel as well, I will get one of those as soon as I can.

jim

[Pirate88179]

dasimpson:

I have never heard of these devices until Jim posted about them.  I have never seen anything like them here in the states.  It sounds like a very handy device to decide what the resistance should be.

If anyone knows where these can be found here in the US please let us know.

Bill