Crackling Bifilar Demo Board for Evaluation

[Peterae]

I am working on a demonstration board for the purpose of posting out to some of you to evaluate the crackling noises i have been getting in a bifilar coil.

I have done away with the need for expensive phase delay chips to drive the bifilar by using 2 separate pic white-noise generators these generate 2 streams of random Mark/Space pulses which then get fed to ZVN4306A Fets to drive each half of the bifilar coil.

I am only in design mode at the moment and have not yet tested or debugged the prototype.

Here's the circuit NOTE i am trying to keep it as simple as possible to show the effect.

ZVN4306A Data sheet
http://www.diodes.com/datasheets/ZVN4306A.pdf

[BEP]

Let me know what you want for it.
My laser printer has been down for quite awhile.
I have the chips, programmer, etc.

Cover your costs & time!

[Peterae]

Hi Wave
All i will ask is the cost of postage, i have the parts to build about 5 of these but may order some more bits if needed, It's a simple circuit and doesn't cost much anyway.

I need to build the prototype yet to make sure it works, i have never used this fet and have never driven straight from the port pin before either, i also dont know if having the bifilar on board will stop the crackling or not, so a couple weeks away at the moment.

[Peterae]

New proposed circuit diagram for prototype production of PCB.

Still need to cad PCB, just learning Eagle.

If it works board will drive this coil  
Dual bifilar wound axially over a 1 turn loop of copper coated wire, previously shown 80 Watt anomalous Pulses when 1 turn loop was loaded with a 20Ohm non inductive resistance.

[ion]

Count me in Peter.

"Here's the circuit NOTE i am trying to keep it as simple as possible to show the effect."

Just one suggestion unless it would unduly complicate matters: add a Fet driver chip and two switches to allow each channel to be operated from a SG or the random noise generator. This will make it more flexible.

I guess it is possible to later program the chips to make a SG.

If these ideas will complicate things, disregard.

BTW, none of the PM enhancements such as: bold, underline, strike,italics, quote or emoticons are working when I go to PM someone. Is this just my computer?

[Peterae]

Well how about unplugging the pic and having a post on the PCB to connect a clip to inject a signal for each chan, i would prefer to not add switches if possible.

Not sure i will check the extra functions out on PM

[giantkiller]

The crackling noise comes from the ecliptic percussion of the very highest of switching speeds attaining synchronization. Basically, you have a virtual stun gun. Crank the power up above 48vdc and you should EMP your bench equipment.

[Peterae]

Hi gk

2 Channel whitenoise injection.

OK I've switched to a single channel board, this way we can make as many channels as we require, makes the PCB smaller and does not necessarily tie it to this project, I've also added a BNC for signal injection.

Now i still have some real estate on the PCB for something else if anyone has suggestions.

How about a variable EMP detector 

[Chet K]

Peter
Quote
How about a variable EMP detector
--------------------------------------------------

Actually that would be quite nice.............

Thx
Chet

[ion]

Nice job Peter

My suggestion would be to add two small ten turn trimmers to the unused analog inputs (if it has them) and a switch to transfer from white noise to SG mode. Trimmers would be duty cycle and frequency.

[Peterae]

Hi ION
Oh i see what you mean now, actually it would be pretty hard to turn that pic into a reliable variable mark/space & frequency generator, but i wonder if we could place one of those MC34063 chips on board and switch between the 2, might make the board a little larger but hey that would not matter and make it a whole lot more usefull for general switching, as i am not familiar with that chip i will start reading the datasheet and see what's involved.  

Maybe a 3 way switch Pic/BNC/SG

Thanks
Peter
EDIT OK i cannot see the MC34063 being capable ofthat either, 555 timer maybe, I'm not saying i cannot make the pic micro do the above but it wont be pretty and probably very poor frequency range, difficult to know unless i think on it some more.

[ion]

The TL494 would be a better choice as it can do 0 to 95% duty cycle (pot adjust)  and frequency from 10 kHz (or much lower depending on initial capacitor value) to 500kHz. with a potentiometer. It is a very versatile chip with push pull or parallel drive, comparators, reference etc.

[Peterae]

Yeah lets forget the code idea, only 10 bit A/D's anyway, good for duty, not good for frequency resolution.

Yes TL494 is a great candidate, so we don't need the BNC right  

I don't think it would be good to go over 50% duty.

by the way i have not found anything about your smileys and BBC code being able to be disabled, stumped at the moment.

[Peterae]

OK how about this

2KHz to 100KHz duty 2.5% to 100%, i need a resistor in the leg of the Duty pot to limit the Duty to 50% but could not work out if it was high side or low side, hopefully you will know and i will draw that in, also offcourse we can change resistor or capacitor values to suit.

I used a jumper in the end for selection between the pic and TL hope that was ok, it saves a bit of space and cost.

Here's my circuit

[ion]

Hi Peter

Maybe for maximum flexibility of the TL494, bring pins 1,2,3 ,13,14,15,16 out to pads so that they can be wired with solder jumpers per your schematic or other modes as needed without having to cut traces.

Don't fret about my problems with messaging, I think the problem is on my end. I will test on another computer.

[Peterae]

Hi ION
OK here's first draft, i will sleep on your pad request and have a think to work out how to implement it 

Cheers
Peter

[Peterae]

OK how is this, i could do the pins you suggested, Managed to do 1 of the drive transistors, I've done it so link wires can be used for my config and any changes needed can use pins or wire etc.

Diagrams a bit of a mess now LOL

Anything else ? 

[From Other Planet]

Dual bifilar wound axially over a 1 turn loop of copper coated wire, previously shown 80 Watt anomalous Pulses when 1 turn loop was loaded with a 20Ohm non inductive resistance.

Hello Peter, just did some digging to find this thread again 
I wanted to  ask if you maybe know/want to share the parameters of the 3 coils/conductors involved (especially lengths and weights)
I'm asking because I'm very interested in the ratios of these in different devices, and believe its critical for operation. This topic currently is also being discussed on Dally thread over on OU.com

kind regards
Manu

[Peterae]

Hi OtherPlanet
Actually with this setup the whole point was not to rely on set frequencies, i was driving each of the coils with a broad spectrum whitenoise signal, so that the magic frequency/ Harmonics where there but only once in a while, up to this point i knew there must be a magic combination to release the energy but could not find it, so light bulb moment switched to whitenoise, which did the trick.

i cannot tell you how much wire is on the dual yellow windings as the coil is glued down to the whiteboard but i can go measure the diameter if you need it, but honestly my system would work with any diameter because of the whitenoise.

Peter

[From Other Planet]

Hi Peter,
I understand. Very clever way of surrounding the anomalies 
I not need the data for a specific build or wanted to do replication of ur setup the next days, i trust your measurement skills on this. Just wanted it for my personal collection of information,
especially concerning these parameters, so no urgency here.
If u somewhen get back to that setup and note diameters here, would be cool. Maybe plus inner and outer diameter of toroid, then could calculate.

kind regards

[Peterae]

Sure, i will have a look later tonight, for the central core i used Cheap TV coax but stripped the braided screen off and kept the air holed plastic insulation and central core, it turned out it was cheap TV Coax because a magnet sticks to the central core and therefore i deduced it's actually copper plated iron wire.

[Peterae]

OK OP

17cm OD
15.5cm ID

Yellow wire Dia measures at 1.34mm dia with insulation
totall width of coax with bifilar is 7.5mm

coax copper coated iron wire measures 1.1mm dia
Coax plastic insulation measures about 4.84mm dia

there are just short of about 400 turns of yellow and because it's a bifilar we are probably just short of 200 turns per coil, they are wound very tight down the length of coax insulation.

Cannot tell for sure if the yellow wire is multicore or single stranded, i bought both around the time of construction and cannot remember which i used.

With a 20Ohm non inductive resistor across the single core i was getting about 80Watt pulses randomly occurring when driven with 2 wideband whitenoise driven fet stages, the whitenoise was produced using a pic that was outputting random pulses widths, the algorithm & design can be found on one of the threads in my bench.

[From Other Planet]

Thank you very much for sharing your time and data with me!