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: TP600 - TPU PULSER  (Read 24304 times)

dutchy1966

  • Sr. Member
  • ****
  • Posts: 344
Re: TP600 - TPU PULSER
« Reply #15 on: July 26, 2007, 04:39:04 PM »
PULSE WIDTH QUESTION

@All,

What range of pulse widths would folks here like to have?

Here are some examples:

1) 100ns ~ 500ns in 100ns increments
2) 50ns ~ 250ns in 50ns increments
3) 20ns ~ 100ns in 20ns increments
4) 2ns ~ 510ns in 2ns increments (deluxe $$ implementation)

Perhaps longer than 500ns?  ???

Thanks,
Darren

Hi Darren,

Personally I think option 3 is the best. I understand what you're saying about the rise time of the MOSFETS but, at some point, we might find others that are faster than than the 50 ns. It would be nice that we could just replace the mosfets and don't need to change the rest of the circuit.

I suppose you mean to want to leave an option in there to use 50% duty aswell? Like a switch that can select 50% duty or a variable (very) small duty cycle.

Hope this helps....

Robert 

wattsup

  • Hero Member
  • *****
  • Posts: 2606
    • Spin Conveyance Theory - For a New Perspective...
Re: TP600 - TPU PULSER
« Reply #16 on: July 26, 2007, 05:58:24 PM »
@z_p_e

Thanks for your explanation. This is really not what I had in mind at all. With all due respect, in my opinion pulsing negative only is a dead end. Frequencies or not.

If you apply a current to a wire and stop it before it reaches the end of the wire, you will get the Tesla effect. You cannot do this if you are pulsing the negative. There is no inrush and you are just blocking the BEMF. The BEMF is faster than the electricity flow so before the flow even stops, if the BEMF knows where the negative is, it will know where the positive is and recede back into the positive before the current actually stops. The field is faster than the current. Maybe 1000 times faster, we do not know.

This is what I am thinking is happening. When you get BEMF, the BEMF is blind and has two options. Either it can touch the negative (like a blind man using his cane to tap the ground) to then know where the positive is, into which it will recede, or, if it cannot touch the negative, it just stays put, does nothing and creates heat. This second option or action on a pair of wires is nothing, produces nothing and is analagous to the current ECD.

Now, please understand that this is my view, the view of an EE-Neophite (EEN) but because of my EENism, I see the circuits more as living circulations then as static components. This also stems from my 20 years experience in water treatment technologies working with complex systems and processes. And from what I can see even in Otto's ECD is a stuck negative, everything is trying to go through this open and closed door while you are pushing voltage forward continuously. There is no play. There has to be some play, a place for expansion and contraction for a device to live on its own. A place where energy can be conserved and not wasted.

z_p_e there are some great thinkers and doers on this board that do not all have the EE acumen but have their insights that are not masked over by such EE knowledge. Most of the time you guys are talking tech shop, we are simply lost if the shuffle so many of us EEN's will just sit back and wait it out. Because our rebuttals may seem too simplistic, so in many instances, it is better to say nothing. But, if you have to think out of the EE box, sometimes it's is an advantage to already be out of it.

So I feel what we are doing is working backwards. Most are trying to get the big flash, major output, when we have not even see one watt, grow to 2 watts, we are working trying to get 250 watts and more. If you can just get 1 extra watt and do this 250 times, there's your 250 watts. How can a whale scratch a living off of tiny krill.

In my view Otto already had a good start of an answer with his 50 turns around the finger and ONE wire going through. What if you had 50 of those in parrallel working off a simple little spark. Sparks are easy to make and very powerfull. Work out the small and you'll find the big.

This is why I asked my questions. To work out an OU unit, you will require the flexibilities given in my questions and more in order to have a fighting chance. Otherwise, with just negative pulsing, you will be wasting precious time. If you want to practise your hunting, it is best to have a good variety of traps. If you only have one trap and it is the wrong one to begin with, then you are wasting time. Same goes for fishing if you only have one lure, good luck.

I think what I may have to do to get my idea across is to make a block diagram showing the logic. I think alot of you guys are not on the right track with negative pulsing. You need the negative solid for BEMF, or you have to have a complimentary switching to send the BEMF to a capacitor when the negative is open, otherwise you're wasting juice and producing heat.

Now again, maybe I fail to see the logic of this and I would appreciate if you could explain the benefits of negative pulsing to me in laymans terms with an example of a block diagram or simplified circuit. I just don't see it. Also, I hope I did not put this in a bad way as I do respect your abilities tremendously and know your views are essential.

z_p_e

  • elite_member
  • Hero Member
  • ******
  • Posts: 651
Re: TP600 - TPU PULSER
« Reply #17 on: July 26, 2007, 06:30:34 PM »
Thanks for all the good feedback guys, I appreciate it.

I am still digesting it however, and have been brainstorming all morning to come up with a way to make everyone as happy as possible in terms of frequency range and pulse width capability. So far it looks good ;)

Regards,
Darren

z_p_e

  • elite_member
  • Hero Member
  • ******
  • Posts: 651
Re: TP600 - TPU PULSER
« Reply #18 on: July 26, 2007, 06:44:06 PM »
wattsup,

I must admit that I am better at understanding technical descriptions as opposed to figuring out what someone means using laymen's terms.

I'm not following what you mean by "pulsing the negative", and I'm also not sure why you want the bemf, or why you feel it is "faster" than electricity.

If you want the bemf, no problem...just eliminate the freewheel diode across the MOSFET. Just be sure that you DO SOMETHING with the bemf however, or it may take out the MOSFETs with HV spikes.

So if you could describe what you mean in a little more technical terms, perhaps I can see where you are coming from and hopefully explain the differences (if there are any) to what the circuit is already doing. A block diagram if you wish may be helpful.

No offence taken wattsup. I understand that you may have a different point of view in what's going on and what needs to happen, and that's ok. But I need to understand that point of view before I can comment.

What is "negative pulsing"? What is "positive pulsing"? What is the difference in your opinion?

Cheers,
Darren

turbo

  • Guest
Re: TP600 - TPU PULSER
« Reply #19 on: July 26, 2007, 07:55:47 PM »
in my opinion, the bemf is working against us, meaning it's a pulsed flow in the other direction as the one we want our magnetic field to go.
therefore we need to elimminate it resulting in a magnetic field which goes one way only so we can speed it up fast.

Darren, is there a way to add crystals to the circuit?

Marco.

BEP

  • TPU-Elite
  • Hero Member
  • *******
  • Posts: 1289
Re: TP600 - TPU PULSER
« Reply #20 on: July 27, 2007, 02:22:46 AM »
Just a suggestion:

Instead of using the freewheel diode to direct the BEMF past the MOSFET to ground or negative or whatever - connect it so it redirects the BEMF to a counter-wound coil so the energy - as little as there may be - is used to promote the process.

You protect your MOSFET, create a faster fall-time for the coil generating the BEMF and make use of the energy.

Am I on the wrong track ZPE?

MarkSnoswell

  • TPU-Elite
  • Full Member
  • *******
  • Posts: 197
Re: TP600 - TPU PULSER
« Reply #21 on: July 27, 2007, 02:55:06 AM »
Hi ZPE

Here are the features I would like in a generic lab pulse controller:

Controller
AD9959 Quad DDS
PIC (or ARM) controller - programm in place capability.
USB control option would be great for people wanting to drive it from their computers.
Stand alone unit like -- http://www.minikits.com.au/sweep.htm
Pulse width control down to 10ns  (the DDS's only output square and sine)

Output board
Opto isolated
Selectable Monostable mode for fastest pulse width for any given mosfet -- perhaps a triggered blocking oscillator design.

There are great benifits in keeping the controller and output stages separate...
I expect that the mosfet and diode selections will vary quite a bit depending on the project -- and will get blown up on occasion! I would be looking at a range of output stages including valve output stage.


The AD9959 is able to potput dar faster and more precisely timed signal then we require. But here are the specs I would anticipate using in the first instance:

30Khz - 1Mhz range
0.1Hz control
Slow sweep capability.
Fast frequency modulation on any output. - for sread band rather then off peak tuning.
Pulse width -- fastest possible by output device.


A note on mosfet rise times -- we arent driving current, we just want voltage spikes. At low current the rise time for the mosfet will be much higher than the full load figure -- so a 4V/ns device may in fact deliver 100+v/ns in the mode we are using it. This is why a triggered monostable output mode would be good -- to get the fastast pulse possible given output device and load.

cheers

mark.

z_p_e

  • elite_member
  • Hero Member
  • ******
  • Posts: 651
Re: TP600 - TPU PULSER
« Reply #22 on: July 27, 2007, 02:44:43 PM »
Just a suggestion:

Instead of using the freewheel diode to direct the BEMF past the MOSFET to ground or negative or whatever - connect it so it redirects the BEMF to a counter-wound coil so the energy - as little as there may be - is used to promote the process.

You protect your MOSFET, create a faster fall-time for the coil generating the BEMF and make use of the energy.

Am I on the wrong track ZPE?

BEP,

This is an excellent idea and certainly an option for anyone to try.

It's just a question whether it will promote the process or detract from it. Also, shunting the bemf through the original coil (as shown) may be promoting or detracting from the process as well. So one should perhaps try both ways.

At any rate, SOMETHING has to be done with the bemf. It could even be used to charge a capacitor (eventually...these spikes are likely VERY short indeed).

Regards,
Darren

z_p_e

  • elite_member
  • Hero Member
  • ******
  • Posts: 651
Re: TP600 - TPU PULSER
« Reply #23 on: July 27, 2007, 02:56:51 PM »
Hi Mark.

Thank you for the AD DDS chip info. I'm certainly interested in these, and have been since first seeing them a few months ago.

I would definately like to develop a generator based on one of these chips, but for now, the TP600/900 will do well for many folks, and for many applications.

Perhaps I will work with Peterae in developing one of these DDS generators soon.

Cheers,
Darren

z_p_e

  • elite_member
  • Hero Member
  • ******
  • Posts: 651
Re: TP600 - TPU PULSER
« Reply #24 on: July 27, 2007, 03:07:22 PM »
in my opinion, the bemf is working against us, meaning it's a pulsed flow in the other direction as the one we want our magnetic field to go.
therefore we need to elimminate it resulting in a magnetic field which goes one way only so we can speed it up fast.

Darren, is there a way to add crystals to the circuit?

Marco.


Marco,

A crystal could be used, but not sure why?

Using a crystal eliminates, or at least severely limits frequency adjustment unless dividers are use. With dividers comes resolution limits too.

Crystals provide stability, but are inherently difficult to "adjust". One solution could be to use a PLL with a crystal reference osc., but again the frequency range and adjustment is limited. Also, this is becoming quite a different animal than the original intent of the circuit. I would sooner go the DDS route than use crystals and PLL's.

So, in the end a DDS unit might be the best. However, don't give up hope for the TP900. It will have a good frequency range and PW adjustment.

Regards,
Darren

PS. I hope to post the TP900 circuit very soon.

turbo

  • Guest
Re: TP600 - TPU PULSER
« Reply #25 on: July 27, 2007, 03:11:46 PM »
the bemf can be extracted by using diodes and then fed/redirect into the same bifilar coil only the other winding, so it cancels itself out ,i have already tried that and you can also capture the bemf in capacitors etc..

Marco.

Peterae

  • Sr. Member
  • ****
  • Posts: 327
Re: TP600 - TPU PULSER
« Reply #26 on: July 27, 2007, 05:51:12 PM »
Hi Darren

I see you are doing a Stirling job over here. ;)
The DDS would be very nice but inherently the cost of building would climb and take some time to get the software up and running, until we have a clearer vision of the exact function of the control we require I think it would be best to keep design time and build costs down to a minimum.
The TP600 should be able to keep most experiments on track and using CMOS it's difficult to get much cheaper.
I am a bit of a module fan myself and tent to build modules that plug together to create the required circuit.
Your above circuit, I would build each oscillator as one small board that plugs into the sync board which plugs into the fet driver and fet output board, that way if the oscillator or the sync board needs to be modified and redesigned for other purposes we just need to rebuild a small board instead of the whole board.
Also using photo etching to make the PCB's would mean you only need to cad the oscillator once and build 3 times as a module.
This method has been very handy with my own board as I can unplug a pic processor and plug a 555 timer based oscillator directly in place, and now thanks to your great simple oscillator circuit I can plug one of those in for a complete set of frequency ranges when I get round to cad-ing it up to a PCB.

Peter

Earl

  • TPU-Elite
  • Sr. Member
  • *******
  • Posts: 435
TP600 - TPU PULSER
« Reply #27 on: July 27, 2007, 06:30:05 PM »
@Darren

good work, keep it up.
I believe when SM refered to a pure frequency, he meant low jitter.  That means a quartz crystal reference somewhere.  Whether PLL, dividers, DDS doesn't probably matter so much as long as jitter is low.

This rules out R/C oscillators of any kind, should jitter be of extreme importance.

Low jitter also means short leads, lots of low-inductance by-pass capacitors, etc.
GHz layout, not wires all over the table.

@All,

take a look at my latest ideas at:

Fastet, narrowest pulser possible
http://www.overunity.com/index.php/topic,2582.msg41929.html#msg41929

Rat Race version 2
http://www.overunity.com/index.php/topic,2582.msg41932.html#msg41932

Rat Race version 1
http://www.overunity.com/index.php/topic,2582.msg38506.html#msg38506

Regards, Earl

turbo

  • Guest
Re: TP600 - TPU PULSER
« Reply #28 on: July 27, 2007, 06:47:30 PM »
the transistor setup will generate the unwanted harmonics all over the place, that is why the tubes work much better and crystals do not generate these unwanted harmonics they are stable the only thing which alters their frequency is, temperature.
when using transistors we may also need to use pre amp like tools to reach proper feedback like Steven said ,tubes are much diffrent.
M.



BEP

  • TPU-Elite
  • Hero Member
  • *******
  • Posts: 1289
Re: TP600 - TPU PULSER
« Reply #29 on: July 27, 2007, 07:05:25 PM »
To answer a PM request I offer the following: