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Making a Joule Thief Circuit with Steven Chiverton – Part 2

Continued from the Previous Article

Dude i used to
get bad head aches and stuff playing with air core coils so be careful putting
higher volts in them..i once put so much in to my coil it cut my radio off 10
feet away and i almost blacked out.. so i killed the power and i was in a state
of confusion for like 2 hours after that.. it took a long nap to fix me.
so be careful!!
Above is the
latest radiant energy battery charger joule thief  circuit I built from youtube video, the coil
I wound 114 turns bifilar wound onto the core I got from xxxx electronics for
around $9 
and on one of my
tests I adjusted the circuits 1k pot till the neon lite up and no heating was
felt in the power transistor since ive put it on a heatsink, a thick heatsink
but when I used my 12 volts sla battery with just over 10 volts left in it I
got over 131 volts out from it,  14 times
more output than I did get from the input 
ill conduct more tests  and put
them down here , to see what outputs I can get from various inputs .
the 12 volts 7.2
amp hour rechargeable sla battery with just over 10 volts left in it I got over
131 dc volts output from the latest joule thief circiut.
Here are the
results for various batteries and voltage inputs
1aa battery 1.5
volts type 1.04 volts left in it I got 7.55 volts output from the joule thief
a23 energizer
battery 12 volts type had 9.62 volts left in it and I got an unusual reading of
4.23 volts out a voltage loss
yellow click rechargeable 1.5 volts battery, 1.09 volts left in it I got 1.20 volts out from
the radiant energy battery charger joule thief.
Ag13 button cell
battery 0.397 volts left in it I got 01.3 millivolts out of it
L1154 button cell
1.304 volts left in it  I got 4.50 volts
out of it through the joule thief circiut.
Ag10 button cell
battery it had 1.16 volts left in it  I
got 4.3 volts out of it through the joule thief circiut.
357a button cell
battery  with 1.359 volts left in it  I got 5.55 volts out of it from the joule
thief circuit.
Latest joule
thief circiut test . with the potentiometer turned up I adjusted it  till the neon come on and then I adjusted it
to the max and the voltage reading was over 145 volts and the neon stayed lite
and when I turned it down it still stayed lite like it was getting extra
voltage all of a sudden . and the circiut unlike the other dident even make
that high to low pitch sound , when I adjusted it fully up and down so I don’t
know why . so after I got the neon lite it stayed on when I turned the pot full
down and back up again . and no heat was felt in the transistor after the quick
With the 1k pot
set to highest resistance the voltage output was 132.6 volts  and the neon is not lit  till I turned the pot resistance down to  a level where the voltage has increased to
around 137.0 volts,  and voltage rises
around here again to 145.7 with the neon still lit.
Turning the pot
resistance down the neon dims at around 91.0 volts and when turn the pot down
more to decrease the resistance of the pot more , the neon gets bright again
like its getting more voltage and the circuit then squeals like a camera
photflash circuit charging up its high voltage 
photo flash capacitor.
The voltage was
then 96.8 volts and climbing.  And by reducing the resistance more circuit appears to squeal more,  and the neon is still lit bright even when
the voltage is at 93.6 volts.
 And when I turn the pot up to increase
resistance neon got brighter at 73.9 volts, 
and the voltage rose to 99.8 volts 
turning pot up more to increase resistance  neon got brighter at 152.8 volts  to 153.5 volts and when pot was back at full
resistance the voltage was then  159.4
volts then it dropped to 135.5 volts.
Note that when
the pot resistance was turned down to the point that the neon comes on  neon stayed lite  all the time despite getting dim here and
there then going bright again during the adjustments  and the neon never went out again despite
adjusting the pot fully to the end either way  during the tests  the only way to
make the neon go out is to  disconnect the
battery  lead , the test can be started
again by turning the pot up full, then  connect the battery lead then slowly reduce the pots resistance till the
neon lights again .
Ive recharged my
sla battery up to 12.48 volts and then I fired up both joule thiefs and found
that even with my latest radiant battery charger joule thief im getting less
voltage output for more voltage input and before it was more voltage output
from less voltage input and since the latest tests the battery has gone from
12.48 to 12.1 volts  I used .47 volts so
far , this is getting strange  and
dureing the testing the voltage output did go over 100 volts but dident make it
to the higher voltage I got before I topped up the 12 volts slr battery. As for
the fluro bulb it only lit up a little bit more but not fully so I need more
current or voltage to light it fully
First joule theif
battery charging tests . results
Button cell
battery  ag13 battery brand name sun king
this battery had only 00.6 volts left in it , I used my first joule thief
battery charger to tests it and after a count of 20 it gained enough power to
power one of my small joule thief circuits it now has 1.48 volts in it for charging for 20 seconds .
I tried to charge
2 other button cell batteries but they are to far gone and lose charge fast I
decided to try and recharge this tiny watch battery out of one of my watches
and its been flat for ages so after 3 seconds of charging , it got hot so I
let it cool down and I tested it on a small joule thief circuit and it got  enough power in it to light the led so it
worked 3 seconds was the fastest charging time for such a small battery now my
watch is going again. And I didnt get the details of this battery and measure
its charge left and after I charged it for 3 seconds .
The 2 button
cells that couldn’t be charged I charged them for a count of twenty like the
other one  but when I turned the
potentiometer up towards the full to try get more voltage into it, it reverse
charged so I ended up with a negative charge when I measured its voltage but
still it kept going down so id say they are to dead or no good  at all . it was a good thing I halted the
charge time for my tiny watch battery after 3 seconds when it started to get
hot otherwise it may of exploded but now its perfect ill note the day I charged
it up today monday may 24th 2010 
just before 7 o clock in the evening I think lets see how long its lasts
for till it runs flat .
Ive seen and
saved a youtube video on the a23 12 volts energizer and the man dismantled one
and it had no carbon and carbon rods in it but it had 8 unmarked button cell
batteries in it.   my  a23 energizer I tried to charge it up more as
it was just over the ten volts in it but I managed to get just over 11 volts
into it and the voltage was dropping so something was wrong inside it , so I
dismantled it and indeed found 8 button cells inside it  one had green corrosion  around it and its voltage wasnt steady it
appeared to climb slowly and the rest all had over one volts in them and  I measure everyone of them and also I was
able to power my small joule thief with them and get the 3.3 volts led to light
up to  they will come in handy to .
Below is a
picture of one of my smaller joule thief circuits  built from a schematic from the net I
designed the printed circuit board for it and 
notice the modified plastic cloths line peg, I use that to hold button
cells for testing and the strip of blue tac at the top is my button cell holder.
 Most of the batteries on the strip of blue tac
was from inside the small 12 volts a23 energizer battery.

One of my a23
energizer button cells was getting a bit low it had a measured charge of only
1.179 volts left in it.  this made the joule
thief led dim so I used my larger radiant joule thief battery charger and
charged  it up till it got hot , then I
re measured that battery s voltage and it worked , I successfully charged it up
to 1.346 volts and it now works better and the joule thief  white 3.3 volts led is brighter now.
 Below is my 2
radiant battery charger joule thief circiuts the one on the left without a
heatsink is the one I used to seccessfully charge my a23 energizer button cell
up with. Which was one of 8 button cells found inside the 12 volts a23
energizer battery.

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