Joule Thief

[gadgetmall]

Hi Gadget,
There is another difference that I can see.

In the one you sent out I see a 12 or maybe 11 turn inductor wire which appears to be coming out of the toroid.

Did you "clean this up?"
I do not see it on the new one.
I believe this would add significantly to the output of your circuit even if it is not on the secondary, wherever it is if it is getting pulses, it is converting them to higher volts.

I am referring to the tight spiral on the upper right of pic 1 and I see no such thing on the pic2 same but different one.

jeanna

Well they both have the same wire and same turns 11 on the primary and a spread out 22 turn secondary . Oh i see what you are saying ,No that is an extra part(smally copper coil) laying beside it (messy workarea It's not part of that JT  The placment of the toroids made the wires pull different directions . . As far as the meters  they are correct and both read the same swapped . There will always be a SHUNT in an ampmeter . A Shunt is a load resistor in parallel with the leads . Regardless if the meter is analog or digital . It is obvious as the meter is a near dead short on the JT . On the first jt the light is just lit a bit  with the ampmeter across the Ec but the second one Goes Completly OUT !

Any who Alex will test it . I already did my part and i have an independent Owner who can test it to his hearts content : -)

Thans jeanna for seein one primary is  a bit spread out and the other is not .
Merry Christmas Jeanna and everyone Have peace.

Gadget

[gadgetmall]

Like I said, there's something wrong with gadgetmalls meter readings. That kind of Fluke meter (e.g., Fluke model 27) has ~ 5.6 ohms input resistance in mA current mode, not 100 ohms.

If you get bad measurements then put it on the scope. All I see is something definitely wrong with the measurements. The scope will always save the day.

You are Correct about the resistance It is exactly 5.6 OHMS across the shunt . Near Dead Short in the 300ma scale . But it is accurate to 300 milliams . How can you say it it is wrong if Fluke Build the meter to measure 300 ma in that spot . All meters don't have 100 ohm resistors you know .

[PaulLowrance]

You are Correct about the resistance It is exactly 5.6 OHMS across the shunt . Near Dead Short in the 300ma scale . But it is accurate to 300 milliams . How can you say it it is wrong if Fluke Build the meter to measure 300 ma in that spot .

But your measurements show the Fluke having ~ 100 ohms, when we know it really has 5.6 ohms, so somethings wrong. It's very possible the Fluke is expecting only DC without any AC. Try connecting your fluke (while in DC milliamp mode) to an AC generator (no DC) to see if you fool it into thinking there's DC.

[sparks]

The resistor inside the meter is creating a voltage drop assuming you are feeding it at least filtered dc.  You are not.  You are pumping it with dc ripple. Load that thing down with an incandescent light bulb and measure the brightness and temperature of the bulb. Compared to a bulb in the feed from the battery.  Lets moveon.

[gadgetmall]

I see what your saying now. Is there any other way other than a scope to measure the true current from the rectified  transistor? For instance  use a bridge instead of one diode ?