[K3PZN-List] Joule Thief, That dead battery Voltage Booster project

[Curt Milton]

Phil

your posting of this eclectic perhaps technology certainly has livened up the list.  yes grab those joules before the stuff makes it into a landfill or wherever it goes when its deposited elsewhere.  I miss your presence at meetings (when I actually attend - it takes a teaser of something interesting to hop back into the car after a long day with commutes).  definitely consider bringing something interest to one of our meetings.  

I wish I would have learned more about power supply technology way back when as I got too infatuated with this RF stuff.  of course, still opportunity to learn in ham radio else we become mere appliance operators (ok I confess I have been recently using a rig I did not solder together).  


CUL Curt




On Friday, January 24, 2014 4:59 AM, Philip Karras <ke3fl at yahoo.com> wrote:
 
"Making A Simple Joule Thief (made easy), by ASCAS" : http://www.instructables.com/id/Making-A-Simple-Joule-Thief-made-easy/

I want to thank everyone who tried to help for all the suggestions. I have my circuit working thanks to Mark, AB3KS who invited me over to his place in Frederick. We looked at what I had done and he pointed out that I had attached the wrong wires of the wound toroid together making mine into a non-inductance winding. See wiki: Bifilar coil https://en.wikipedia.org/wiki/Bifilar_coil This shows the Non-inductive bifilar winding connections which is how I connected my toroid. I totally missed the importance of the two dots on the windings in the schematic.

Someone may know so I'll ask, of what use is the non-inductive version?

Anyway, once correctly connected my circuit was working just fine. I discovered that a Tor-62 core, wound with 25 loops has an extremely low inductance of about 45 uH measuring between the two ends so that 50 loops are being measured. With only 25 loops measured my meter registers 000. This inductor then causes an oscillation I measured of around 500KHz with a 1 Volt battery where as a single 20 loop inductor measured at about 120 uH causes the circuit to oscillate at about 5KHz.

Here are some other links I came across after Mark helped me, some of which clearly showed what I was doing wrong and others show much more clearly how to do it correctly.

Joule thief
http://en.wikipedia.org/wiki/Joule_thief

Good schematic and O-scope trace shows what my scope showed.
http://www.bigclive.com/joule.htm - Clearly shows how to connect the windings of the ferrite cord inductors.

"Joule Thief" Circuits, crude to modern... by Dave Kruschke
http://www.instructables.com/id/Joule-Thief-Circuits-crude-to-modern/step5/null/

"Joule Thief" - no IC and no Transformer, by Dave Kruschke
http://www.instructables.com/id/Joule-Thief-no-IC-and-no-Transformer/

73 de KE3FL,
Phil
AEC Carroll County
OES, ORS, & VE
http://cs.yrex.com/ke3fl
Karras' Corner: http://blog.solidsignal.com/content.php/1005-karras-corner
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73 de K3PZN Westminster, MD
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