Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Custom Search

Author Topic: AC from Joule Thief Secondary/pick-up  (Read 132589 times)

Pirate88179

  • elite_member
  • Hero Member
  • ******
  • Posts: 8366
Re: AC from Joule Thief Secondary/pick-up
« Reply #60 on: June 22, 2009, 06:07:03 AM »
Actually, from my small experience with my scope, as well as looking at other JT scope shots, my regular JT's (with no secondary) put out AC as well.  It may very well be pulsed DC but there is for sure an AC component to this, just like the earth battery.

Bill

nueview

  • Full Member
  • ***
  • Posts: 163
Re: AC from Joule Thief Secondary/pick-up
« Reply #61 on: June 22, 2009, 06:35:44 AM »

Hi all
i see Xee2 got it figured out i could not get my picture to post but i am not real computer savy.
but he is right about a good sign wave with this circuit i used darlington transistors as they switched power faster in more bulk but this would be hard to do at low voltage.
Martin

jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: AC from Joule Thief Secondary/pick-up
« Reply #62 on: June 22, 2009, 07:31:20 AM »
@xee,
@nueview,
I think I understand what you are suggesting??

Are you suggesting the second transistor will do what the second set of sparks produce in the drawing?

It might.
I was thinking along those lines when I put together the 2 tier, and found that the transistor was not being used.

The thing about adding another transistor is that it would be very easy for one to cancel out the other. Wouldn't there be a way to use the pulses as they are and they are fairly high in many jt circuits, and then just make more separate secondaries that work off the pulses?

just thinking,

jeanna

TheNOP

  • Hero Member
  • *****
  • Posts: 513
Re: AC from Joule Thief Secondary/pick-up
« Reply #63 on: June 22, 2009, 07:43:30 AM »
a dual transistor circuit is not really required to get AC at the pickup coil.
starting with 3 volt instead of 1.5 would surely help tho.

what is needed to get AC is rise and fall of the current over a time period.

on the pickup there are no reference to a "zero" voltage point.
you could make one with a center tapped coils.
the AC voltage could be biased relatively to an other circuit or earth point it does bot matter it still would have 2 polarities, high and low.
in AC form you can view them as + and -, but only to a reference point.

what a cap is storing is a potential difference.

xee2

  • Hero Member
  • *****
  • Posts: 1610
Re: AC from Joule Thief Secondary/pick-up
« Reply #64 on: June 22, 2009, 07:56:14 AM »
Have you ever tried to make a MK1 type pick up yourself?

No. I do not understand most of what Mk1 is saying. I also do not understand most of what ist is saying. I think maybe I just do not understand the Canadian language. They seem to have learned some kind of electronics that I do not know anything about.


xee2

  • Hero Member
  • *****
  • Posts: 1610
Re: AC from Joule Thief Secondary/pick-up
« Reply #65 on: June 22, 2009, 08:16:23 AM »
@ Pirate88179

Actually, from my small experience with my scope, as well as looking at other JT scope shots, my regular JT's (with no secondary) put out AC as well.  It may very well be pulsed DC but there is for sure an AC component to this, just like the earth battery.

Bill

For a while I was posting both the positive and negative outputs from the pickup coil. But I stopped because the negative output is so small. If you reverse the diode in one of my JT circuits you will get the negative peak voltage instead of the positive peak voltage. In all of my circuits using a pickup coil for the output, the negative peak is so small it is can not supply much power. The negative output is produced by the current generating the magnetic field and this has a slow rate of current change and therefore generates a small voltage in the pickup coil. When the transistor turns off there is a very rapid change in current and thus a large voltage is generated in the pickup coil. You should be able to see that on the scope in the DC mode with the center of the vertical axis set at ground. But, just because that is what I am getting does not mean everyone else will get the same thing.

NOTE: The polarity of the largest output can be reversed by reversing the leads from the pickup coil. I always call the largest output positive.

« Last Edit: June 22, 2009, 08:38:01 AM by xee2 »

xee2

  • Hero Member
  • *****
  • Posts: 1610
Re: AC from Joule Thief Secondary/pick-up
« Reply #66 on: June 22, 2009, 08:20:43 AM »
The thing about adding another transistor is that it would be very easy for one to cancel out the other. Wouldn't there be a way to use the pulses as they are and they are fairly high in many jt circuits, and then just make more separate secondaries that work off the pulses?

The circuit forces only one tansistor to be on at a time and forces both positive and negative pulses to be equal.


jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: AC from Joule Thief Secondary/pick-up
« Reply #67 on: June 22, 2009, 04:29:12 PM »
No. I do not understand most of what Mk1 is saying. I also do not understand most of what ist is saying. I think maybe I just do not understand the Canadian language. They seem to have learned some kind of electronics that I do not know anything about.
Ah yes.

It took me a long time and it took a lot of patience from both of us (some of it was in a raft of pm's) to get me to understand what MK1 was doing. I do think it is brilliant.
The Canadian they speak is french. That helped me a lot. to know that an "a" means "one" sometimes but can also mean "at" because that is what it means in french. Anyway, I will try to help if you want me to.

Here, for a conceptual starters, try this:
the coil is wrapped over the toroid then through the center in the same way throughout. It begins at one spot and progresses to the left a number of turns then turns "progression" direction and goes back to where it started. Then it crosses over (*) the primary or a blank spot and continues on the other side up the same number of turns and again returns to the beginning spot.

* when it crosses over, you can pull out a few inches of wire as in a center tap.

Try it with 10 turns in each way and see what you get.

The "tuning" of the primary to the toroid is important, too, but even though MK1 insists it must be done in the beginning, I believe that as long as you are in the ballpark with a certain toroid, you can fine tune it later.

He disagrees with me on that point, and he may well be correct.

In a way, you could think of it as a center tapped secondary if you connect it that way.
But connect it from beginning to end for the most volts. Then fine tune it for most volts output.

So, xee, give it a try and see what you get.

I like the way Hazens1 makes the primary. It is a wee bit less powerful than the true bifilar, but not much and a very good way to start tuning a toroid, because it is so easy to alter it.

jeanna

nueview

  • Full Member
  • ***
  • Posts: 163
Re: AC from Joule Thief Secondary/pick-up
« Reply #68 on: June 22, 2009, 06:18:37 PM »

I think i would tend to agree with MK1 about the tuning first allot of what tesla did was about power structuring or getting from a high cycle to a lower cycle power curve or as in using the harmonic to do work at another level or should i say from another level as the article you posted talked about only wanting odd harmonics and from a DC any frequency could be attained this would have been important in early radio without tubes.
the article also talks about producing a high stress upon the system so if you push and pull at appropriate times you would double the stress upon the circuit more stress more effect
Martin

jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: AC from Joule Thief Secondary/pick-up
« Reply #69 on: June 22, 2009, 11:32:56 PM »
Hi everybody,

Here is a drawing of the 2 tier circuit in a different way.
I will probably need to change this some more, but I think it shows some of the interesting parts better than any previous drawings.
All of these figures are with a 10 ohm resistor at the battery. The fully charged AAA battery made the basic voltage (=voltage of basic JTC secondary) over 100 volts and I started to blow leds, so, I added the resistor.

The other oddment is the resolution of the scope.
For most figures the probe had to be on the x10 level because the voltage was off the chart otherwise.
But the scope sees more when it is "far away" at x10 than it does when it is at basic 1:1 probe strength.
I do not know how to resolve this.
So, this is what I have now. I hope you will find it interesting too.

jeanna

EDIT, in asking Bill to look at this I came across the description of "nested parallel circuits" I made that up of course, but I think it might help in figuring out what is going on here.
« Last Edit: June 23, 2009, 07:02:04 AM by jeanna »

gadgetmall

  • elite_member
  • Hero Member
  • ******
  • Posts: 1733
    • Alternative Energy
Re: AC from Joule Thief Secondary/pick-up
« Reply #70 on: June 23, 2009, 02:25:30 PM »
Hi everybody,

Here is a drawing of the 2 tier circuit in a different way.
I will probably need to change this some more, but I think it shows some of the interesting parts better than any previous drawings.
All of these figures are with a 10 ohm resistor at the battery. The fully charged AAA battery made the basic voltage (=voltage of basic JTC secondary) over 100 volts and I started to blow leds, so, I added the resistor.

The other oddment is the resolution of the scope.
For most figures the probe had to be on the x10 level because the voltage was off the chart otherwise.
But the scope sees more when it is "far away" at x10 than it does when it is at basic 1:1 probe strength.
I do not know how to resolve this.
So, this is what I have now. I hope you will find it interesting too.

jeanna

EDIT, in asking Bill to look at this I came across the description of "nested parallel circuits" I made that up of course, but I think it might help in figuring out what is going on here.
Hi Jeanna . Nice Drawing with those little coils :) do you want this to produce more voltage ? then if Yes we need to add a tank circuit . if you dont mind can i take your schematic and add to it . the next thing is multiply the outs, which one  ? all of them need higher volts ? Ac and or Pulsed dc or rf  ? .Very Busy enev thought I'm retired :) I have a 7 years old and she has two summer camp and bible camp back to back this summer as you know i am single so . i'll pop in and out and check up the progress .
Gadget

stprue

  • Hero Member
  • *****
  • Posts: 1025
Re: AC from Joule Thief Secondary/pick-up
« Reply #71 on: June 23, 2009, 04:38:15 PM »


I will use the 2N3055 for the chokes and the biggg ones. Then I will use the magnet and see.

Maybe I will dig out a hazens style and try the magnet on them too.

thanks,

jeanna

Neo's do the same thing to the Hazen design, both change frequence and lower the voltage.  I would like to know what the wave form looks like with magnets put in various place on a JT coil ie base collector primary! Could you post this for me...pretty please?

I wish I had a scope!!!!!

stprue

  • Hero Member
  • *****
  • Posts: 1025
Re: AC from Joule Thief Secondary/pick-up
« Reply #72 on: June 23, 2009, 04:50:20 PM »
Ah yes.

It took me a long time and it took a lot of patience from both of us (some of it was in a raft of pm's) to get me to understand what MK1 was doing. I do think it is brilliant.
The Canadian they speak is french. That helped me a lot. to know that an "a" means "one" sometimes but can also mean "at" because that is what it means in french. Anyway, I will try to help if you want me to.

Here, for a conceptual starters, try this:
the coil is wrapped over the toroid then through the center in the same way throughout. It begins at one spot and progresses to the left a number of turns then turns "progression" direction and goes back to where it started. Then it crosses over (*) the primary or a blank spot and continues on the other side up the same number of turns and again returns to the beginning spot.

* when it crosses over, you can pull out a few inches of wire as in a center tap.

Try it with 10 turns in each way and see what you get.

The "tuning" of the primary to the toroid is important, too, but even though MK1 insists it must be done in the beginning, I believe that as long as you are in the ballpark with a certain toroid, you can fine tune it later.

He disagrees with me on that point, and he may well be correct.

In a way, you could think of it as a center tapped secondary if you connect it that way.
But connect it from beginning to end for the most volts. Then fine tune it for most volts output.

So, xee, give it a try and see what you get.

I like the way Hazens1 makes the primary. It is a wee bit less powerful than the true bifilar, but not much and a very good way to start tuning a toroid, because it is so easy to alter it.

jeanna

xee let me know if you figure out how to wind a mk style coil and please post some pics, I still don't think I'm doing it right!

jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: AC from Joule Thief Secondary/pick-up
« Reply #73 on: June 23, 2009, 06:33:28 PM »
Hi everyone,

I will attempt to make a short verbal description of the MK1.

Overview first:

All the winds go the same way...from over the top through the center and around and up again.
You will be wrapping the coil in 3 directions ultimately. (because it is a toroid, this means the mags move 4 times)
Start at the bottom and end at the bottom.
You will end up with 2 wires.

In this example the total winds will be 40.
OK here goes:

Starting at the bottom left side leave a nice long tail for later connections  and
wrap the wire up 10 times
wrap one more then return to the bottom.
(if you don't understand this, draw 10 hatch marks on a paper then count the spaces in between them)

At the bottom, after you have wound 20 turns  you are coming out the bottom, so go over the primary windings and continue through the center.
(you can pull out a few inches for a center tap before diving through the center again.)
Continue winding 10 more turns up the right side and
wind one more and
wind down the right side to the bottom.
The total turns is 40.

Leave a nice tail.
Cut
sand tails-connect, and - tune.

(of course, you can wind the opposite way from my description; but, the point is to stay wrapping the same way throughout.)
Keep the crossed wires in the center if possible and on the outside put the down wires in between the up wires.
======
Quote
Neo's do the same thing to the Hazen design, both change frequence and lower the voltage.  I would like to know what the wave form looks like with magnets put in various place on a JT coil ie base collector primary! Could you post this for me...pretty please?

I wish I had a scope!!!!!
hmm, I will do what I can. As you may remember my scope does not have a backlight and there is a lot of glare.

The wave stays the same shape but it gets narrower and shorter.
As the frequency goes up (waves are skinnier and closer together) the voltage goes down. (peaks of the waves are not as tall.
Kubikop has a nice shot of this one on a video of a jt. He is showing the wave of a jt on his scope, the he says, "now, I want to show you something..." and he snaps 2 neos onto the toroid. bam! the wave crunches together and gets shorter. Same happens to my all the time. (I had seen this consistent paired-change while tuning the primary with a scope. Every time the volts went one way the freq went the other.)

jeanna
« Last Edit: June 24, 2009, 03:21:03 AM by jeanna »

stprue

  • Hero Member
  • *****
  • Posts: 1025
Re: AC from Joule Thief Secondary/pick-up
« Reply #74 on: June 23, 2009, 07:02:33 PM »
Hi everyone,

I will attempt to make a short verbal description of the MK1.

Overview first:

All the winds go the same way...from over the top through the center and around and up again.
You will be wrapping the coil in 3 directions ultimately. (because it is a toroid, this means the mags move 4 times)
Start at the bottom and end at the bottom.
You will end up with 2 wires.

In this example the total winds will be 40.
OK here goes:

Starting at the bottom left side leave a nice long tail for later connections  and
wrap the wire up 10 times
wrap one more then return to the bottom.
(if you don't understand this, draw 10 hatch marks on a paper then count the spaces in between them)

At the bottom, after you have wound 20 turns  you are coming out the bottom, so go over the top and the primary windings and continue through the center.
(you can pull out a few inches for a center tap before diving through the center again.)
Continue winding 10 more turns up the right side and
wind one more and
wind down the right side to the bottom.
The total turns is 40.

Leave a nice tail.
Cut
sand tails-connect, and - tune.

(of course, you can wind the opposite way from my description; but, the point is to stay wrapping the same way throughout.)
Keep the crossed wires in the center if possible and on the outside put the down wires in between the up wires.
======hmm, I will do what I can. As you may remember my scope does not have a backlight and there is a lot of glare.

The wave stays the same shape but it gets narrower and shorter.
As the frequency goes up (waves are skinnier and closer together) the voltage goes down. (peaks of the waves are not as tall.
Kubikop has a nice shot of this one on a video of a jt. He is showing the wave of a jt on his scope, the he says, "now, I want to show you something..." and he snaps 2 neos onto the toroid. bam! the wave crunches together and gets shorter. Same happens to my all the time. (I had seen this consistent paired-change while tuning the primary with a scope. Every time the volts went one way the freq went the other.)

jeanna

Jeanna thank you for the description, I will make another attempt at making the MK.  You didn't make mention of the cross overs though!  So I don't actually cross over any windings either outside or inside the diameters of the coil, right?  Looking kinda of like an XXXX  I'm guessing!


It needs to look like this //////////up and then returning ////////////////////down?