Re: Modern AC Flyback Transformers
Dr. Slack, Mon Sept 01 2014, 11:57AM

Sounds a really neat bulk-buy component.

What's the rating for the AC output insulation, peak voltage?

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 01 2014, 12:12PM

Sure is, with a induction heater style ZVS ive put more than ~20A at 24VDC into this flyback and its handled it.

With a 10 turn primary, 22VDC loaded @ 17A it was putting out 13.2kVAC RMS @ 28mA and has capacity for more!

Re: Modern AC Flyback Transformers
Erlend^SE, Mon Sept 01 2014, 02:29PM

Very nice.

I have some negative output flybacks.

Who did you order the transformer from?

Re: Modern AC Flyback Transformers
Patrick, Mon Sept 01 2014, 06:07PM

I like AC flybacs too, as theres no guessing the ratings on diodes, diodes to fail, or bizarre resistors and pots hanging off the sides. But, how do you know it's 13.2kVAC and 0.028A ? This would equate to 370 watts.

If so, 13,200 v / 3,000T = 4.4 V per turn.
And 22 V / 10T = 2.2 V per Turn.

so your gaining twice as much output voltage as the turns would allow in a conventional topology. Generally i like Flybacks, as we gain winding advantage, but lose on power transfer. Though in a ZVS mode maybe there's not so much power lost.

With 3000 turns with a 1 inch diameter means Pi x D = C and 3.14 x 1 = 3.14 in x 3,000T = 9,420 in of 28 awg.
28 awg = .213 ohms per meter,
9,420 in to meters = 239 meters.
239m x 0.213 ohm = 51 ohms.

so, if .028A x 51ohms = 1.4 real volts dropped by current (non reactive) 1.4 VAC x 0.028A = 0.04 watts heating in that secondary, so thats good.

have you run it long enough to judge ferrite heat accumulation?

Re: Modern AC Flyback Transformers
Sigurthr, Mon Sept 01 2014, 11:04PM

The circuit he's using uses bipolar ZVS drive iirc so it would be +- 22V seen by the primary. Oh and he said he's inputting 374W. 40mW waste in the secondary sounds really good. As it's ZVS the primary would see only resistive losses too.

I'm definitely interested in at least one.

Re: Modern AC Flyback Transformers
Patrick, Mon Sept 01 2014, 11:25PM

So how much? Does it come with a datasheet?

Re: Modern AC Flyback Transformers
Alex M, Tue Sept 02 2014, 02:11AM

Hi Fiddy, I would be interested in these.

What sort of costs are we looking at?

Re: Modern AC Flyback Transformers
Fiddy, Tue Sept 02 2014, 02:14AM

I have run it for a while and it doesnt ge very hot at all

I do not have a datasheet for the sample but have requested one.

Not too sure on price as of yet, it maybe around $40USD it all depends on the bulk factor.

Re: Modern AC Flyback Transformers
Ash Small, Tue Sept 02 2014, 12:37PM


Then there is postage from Australia.

ZVS runs in push-pull mode, not flyback mode. You don't usually need an air gap for push-pull mode.

If run in flyback mode output voltage should be higher. Flyback mode doesn't depend on turns ratio. The only factor that depends on turns ratio in flyback mode is the reflected voltage seen by the primary (and the switch).

The energy stored in the airgap pushes the voltage up to whatever the load (and current) dictates. The higher the impedance of the load, the higher the voltage. A flyback (in flyback mode) is a coupled inductor, not a transformer.

Re: Modern AC Flyback Transformers
Patrick, Tue Sept 02 2014, 03:00PM

Fiddy, do these have an airgap? When the 13.2 kV was quoted, which mode was it in?

Re: Modern AC Flyback Transformers
..., Tue Sept 02 2014, 03:04PM

Those look pretty nice, very similar to the ones which are used in cheep co2 laser power supplies, which are good for a good kw continuous output power. If you have the option, I would personally rather see one with a little heavier gauge wire on the secondary, although 28awg should still be good for a few hundred mA before it melts down.

At $40 a piece I won't buy 10 but might be in for a few of them, sure beats winding my own

Re: Modern AC Flyback Transformers
Dago, Wed Sept 03 2014, 06:20AM

I'm also interested in maybe a couple of them.

Re: Modern AC Flyback Transformers
Rod-on, Wed Sept 03 2014, 07:35AM

I'd like two of them, I'd like to make a couple of plasma globes

Re: Modern AC Flyback Transformers
Fiddy, Wed Sept 03 2014, 09:43AM

Awesome ill make a list in the OP and then order at least that many soley depenedent on cost.

Meanwhile, here is the production sample running off a ZVS driver @ 24V

Re: Modern AC Flyback Transformers
Daedronus, Wed Sept 03 2014, 01:48PM

I would like to see it running off a full bridge at higher voltage, since I'm interested in higher output voltages.

Re: Modern AC Flyback Transformers
Dragon64, Wed Sept 03 2014, 05:10PM

I'd be interested one of these as well. Though I'm unsure if you're willing to ship to Canada (and also how much the shipping fee will be).

Re: Modern AC Flyback Transformers
hen918, Wed Sept 03 2014, 05:19PM

I defiantly want one (or two)!

Re: Modern AC Flyback Transformers
Erlend^SE, Wed Sept 03 2014, 06:43PM

Neat stuff.

I will probably get myself a projection-TV size transformer with positive and negative CW-triplers built in + AC output sometime.

Mind telling who you buy from? I have some special flybacks here but I haven't made a driver yet.

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 08 2014, 06:05AM

Im thinking of getting 20 made, im discussing price with the manufacture at the moment. Im getting them for $25USD for 20 units, then there is shipping for almost 25kg which raises the price substantially.

Re: Modern AC Flyback Transformers
Patrick, Tue Sept 09 2014, 07:46AM

can i ask what the current limit is on the 28 awg wire? from what the maker recommends. ive smashed flybacks with a hammer, and some have almost invisible wire. So 28 Awg may be infinitely better than usual.

Re: Modern AC Flyback Transformers
Fiddy, Tue Sept 09 2014, 08:01AM

around 1.4ADC is what its rated for.

Re: Modern AC Flyback Transformers
Patrick, Tue Sept 09 2014, 08:03AM

so thats for the pulses in to primary though, right?

Re: Modern AC Flyback Transformers
Fiddy, Tue Sept 09 2014, 08:08AM

no thats for the secondary.

You can wind your own primary using what ever gauge fits, the photo at the top shows 16 gauge wound on the primary.

Re: Modern AC Flyback Transformers
Ash Small, Tue Sept 09 2014, 12:35PM

I'll probably have one, depending on postage costs to UK.

I don't mind combining postage costs with others from the UK if it makes sense to do this.

Re: Modern AC Flyback Transformers
Fiddy, Tue Sept 23 2014, 09:44AM

Okeydokey. Im going to order 15x transformers on Thursday!

Re: Modern AC Flyback Transformers
Dragon64, Tue Sept 23 2014, 02:25PM


Hey Fiddy, I'm wondering if I could have one as well before you order.

Re: Modern AC Flyback Transformers
Fiddy, Wed Sept 24 2014, 01:51AM

Yeah man ill add you to the list.

Looks like ill have to increase the order size, could everyone with a + sign next to their quantity please specify their desired quantity before I confirm with the supplier how many transformers to make.

Re: Modern AC Flyback Transformers
Rod-on, Wed Sept 24 2014, 07:55AM

No + beside my name but I'm in for two mate.

Re: Modern AC Flyback Transformers
Dago, Wed Sept 24 2014, 05:21PM

I managed to get some kind of a group order going on so I'm up for 5 :) Maybe save some on shipping to Finland.

Re: Modern AC Flyback Transformers
hen918, Wed Sept 24 2014, 05:52PM

I have a plus next to my name, two please!

Re: Modern AC Flyback Transformers
Ash Small, Wed Sept 24 2014, 06:12PM

@ Alex and Hen, are you interested in combining postage to UK?

I don't mind who they are sent to, and it could save quite a bit. You are both regular posters here, so I don't have a problem trusting either of you

Re: Modern AC Flyback Transformers
hen918, Wed Sept 24 2014, 07:09PM

Ash, I wouldn't mind. Any ideas about how to do it? I have enough to buy everyone's in the UK and then I could ship them out to you? Or we could all pay Fiddy for them and then one of us could receive and redistribute them?

Re: Modern AC Flyback Transformers
Ash Small, Wed Sept 24 2014, 10:19PM


I suggest we get a price from Fiddy, and then go from there. I shouldn't have a problem raising my share, although I do occasionally have cash flow 'priorities', but I can't see that being an issue here.

Transferring funds via PayPal, for example, is pretty simple these days.

Let's wait for Alex to comment, though, and see what he says.

Re: Modern AC Flyback Transformers
Fiddy, Thu Sept 25 2014, 02:11AM

Well ill have to order more at this stage with these added quantities.

Ok guys ive ordered 25 transformers, stay tuned for production updates!

Re: Modern AC Flyback Transformers
Patrick, Fri Sept 26 2014, 06:27PM

If someone has a high voltage oscillocope probe, it would be fun to compare a DC flyback to this AC ones' output.
Do you know if it has the typical gap?

Re: Modern AC Flyback Transformers
Fiddy, Sat Sept 27 2014, 01:00AM

The gap in the iron core? There is no gap.

Re: Modern AC Flyback Transformers
Ash Small, Sat Sept 27 2014, 10:39AM


It's possible to add a gap, by dismantling it and adding some plastic film or paper between the cores. It only bolts together, it's not epoxied or anything, is it?

Re: Modern AC Flyback Transformers
Fiddy, Sat Sept 27 2014, 12:59PM

There are actually plastic films in between the core joins! They are quiet thin.

Re: Modern AC Flyback Transformers
Patrick, Sat Sept 27 2014, 03:24PM

yeah im not sure if having or getting rid of the gap helps your guys' ZVS type circuits. i mainly use traditional flyback circuits, so for me its essential.

As ashSmall said, we often dont get a choice as there epoxied.

Re: Modern AC Flyback Transformers
hen918, Sat Sept 27 2014, 05:37PM

I know they can use a special bonded ferrite powder that basically means that the "gap" is distributed across the whole core. It means that they can make the "gap" exactly the same size every time. It probably works out cheaper overall as well.

Re: Modern AC Flyback Transformers
Ash Small, Sat Sept 27 2014, 06:23PM


As I understand it, the Mazzilli ZVS circuit is a push-pull, conventional transformer circuit, and therefore doesn't want a gap (there may be exceptions, but I'm not familiar with any, other than possibly to prevent saturation), and traditional 'flyback' circuits are actually 'coupled inductors' (not transformers) and generally do require a gap, not just to prevent saturation, but also to store more energy.

Maybe someone else can shed some more light on this subject?

EDIT:


I also have some old flybacks with three gaps in the leg that contains the windings. Also, they don't always get the 'distributed gap' ones the same every time, due to various production factors, and they are actually measured after production to determine the specification.

Re: Modern AC Flyback Transformers
hen918, Sat Sept 27 2014, 07:13PM

Yeah, the definition of "flyback transformer" is a coupled inductor. Using it for conventional transformers leads to confusion. ZVS drivers rely on the (relatively low) inductance of the flyback transformer's primary windings to keep a reasonably high frequency. If there was no gap (real or distributed) the inductance would be too high and you would end up with ridiculously low frequencies, (usually resulting in the oscillations stalling and one of the MOSFETs blowing up)
If you don't use any sort of gap, you end up with a normal transformer which you can drive with a full/half bridge, but, without the flyback effect, the secondary voltage will not be as high.

Re: Modern AC Flyback Transformers
Ash Small, Sat Sept 27 2014, 07:41PM


I understood that most people remove the gap when using TV flybacks with the Mazzilli ZVS circuit. I've not yet built one myself, so can't be certain, but this is the impression I got from reading threads on the subject. I suppose there would still be some distributed gap, anyway.

Re: Modern AC Flyback Transformers
hen918, Sat Sept 27 2014, 08:01PM

Didn't know that. I never have.

Re: Modern AC Flyback Transformers
Sigurthr, Sun Sept 28 2014, 02:34AM

I do know that for flyback mode (coupled inductor) if the gap is excessive there is excessive reflected voltage on the switching transistor/fet. I was recently asked to test a driver circuit and spent hours scratching my head how I was getting over 600V reflected peaks across the DS of a 100V fet when only using 12Vds supply. I pulled the old flyback apart and found that there was a chip missing from the core right at the gap. I ground down the cores and restored the original ~1mm gap spacing and the reflected voltage went back to the expected 60V. Having those huge reflected spikes caused a tremendous amount of heating in the FET. Really surprised it didn't just blow it up, but I guess the avalanche current was low enough to prevent silicon destruction.

I.e. for a flyback mode you want a gap but don't want it to be excessive. Too small of a gap means too small of energy storage and you won't get the voltage step up you expect. IIRC it does drastically reduce current draw having next to no gap though.

For push/pull "normal transformer" mode you can certainly live without a gap, but it really depends on your drive method. If you have a drive topology that isn't going to get stalled like the famous Mazzilli ZVS then you should be just fine.

One really nice thing about these modern transformers Fiddy has is that we can easily take them apart and vary them to our needs.

I'll just caution the user to watch the output voltage; these are very high turns ratio and probably require oil submersion for EHT applications.

Re: Modern AC Flyback Transformers
Steve Conner, Sun Sept 28 2014, 08:56AM

According to theory at least, the ZVS needs a gap to define the inductance of the core and get a good Q in the resonant circuit. In practice it seems to work without one, it runs somewhere between a LC oscillator and a ferroresonant one where the frequency is controlled by core saturation.

Re: Modern AC Flyback Transformers
Dr. Dark Current, Sun Sept 28 2014, 11:03AM

Hi Fiddy,
have you ordered the transformers yet / is there a place for more orders?
If so, do you know what is the maximum design (peak) voltage output (insulation rating) of the xfmr?

Thanks, Jan

Re: Modern AC Flyback Transformers
Fiddy, Sun Sept 28 2014, 11:19AM



Yes the transformers have been ordered, i ordered 25 and 22 are taken leaving 3 unsold, are you interested?

Maximum design voltage or insulation rating is 83kVpk says the manufacturer.

Re: Modern AC Flyback Transformers
Alex M, Mon Sept 29 2014, 04:17AM


Apologies for the lateness Ash but I have been out of town for a while.

Do we have any more information on the headline costs of shipping to the UK yet?

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 29 2014, 04:55AM


I haven't weighed one of the transformers yet but am guessing 500g - 1kg mark.

I will be using Australia Post, you can put in your details for a quote here:

Re: Modern AC Flyback Transformers
Ash Small, Mon Sept 29 2014, 09:01AM

My initial calculations suggest it may not be any cheaper combining postage, but I'll re-calculate once we have the exact weight.

Re: Modern AC Flyback Transformers
Rod-on, Mon Sept 29 2014, 10:35AM

How long until they are in your hands Fiddy?

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 29 2014, 11:10AM

Mid to late October i will have them.

Re: Modern AC Flyback Transformers
Fiddy, Fri Oct 10 2014, 05:42AM

Hey guys

Transformers have been made and sent, i should have them within 2 weeks.






Fiddy.

Re: Modern AC Flyback Transformers
Artlav, Fri Oct 10 2014, 11:24AM

Wow, almost missed that.

I'll take two (three if no one takes the last one).

Re: Modern AC Flyback Transformers
Fiddy, Fri Oct 10 2014, 12:32PM


There's only 1 left Dr. Dark Current swooped in on 2 of the last 3, there will be one left if you want it?

Re: Modern AC Flyback Transformers
Artlav, Fri Oct 10 2014, 05:48PM

Ok, one is better than zero. :)

Re: Modern AC Flyback Transformers
Fiddy, Wed Oct 15 2014, 10:07AM

Ok guys i have all 25 of them

Now should i connected them all in series?

Re: Modern AC Flyback Transformers
Ash Small, Wed Oct 15 2014, 11:12AM

Ok, so how much do they weigh packed and ready to be sent?

Re: Modern AC Flyback Transformers
Fiddy, Thu Oct 16 2014, 03:02PM

i need to buy weigh scales lol Hopefully they are under 500g each as the postage is cheaper, im on night shift tonight and tomorrow night so wont get around to them until the weekend.

Hang tight.

Re: Modern AC Flyback Transformers
Polonium210, Fri Oct 17 2014, 02:46AM

Would there be any chance of a second run of these?

Re: Modern AC Flyback Transformers
Fiddy, Fri Oct 17 2014, 05:28AM


If there is enough interest i can run a second batch

Ok guys the packaged weight of 1x transformer is 750g which puts us in the 500g> <1kg postage range.

Ill be sending out PM's to everyone very soon in regards to payment.

Mitch.

Re: Modern AC Flyback Transformers
Fiddy, Sun Oct 26 2014, 02:56PM

OK guys find the datasheet attached to this post.


]fiddy_flybacks_datasheet1.pdf[/file]

Re: Modern AC Flyback Transformers
omegalabs, Sun Oct 26 2014, 09:39PM

Can I join? I'm interested in 1 transformer.

Re: Modern AC Flyback Transformers
Dr. Dark Current, Sun Oct 26 2014, 11:08PM

Hello Fiddy,

in the data sheet you say:
"If you exceed 3V per turn on the primary coil by putting too few turns on the primary coil, the secondary voltage may exceed the secondary insulation breakdown voltage and damage the transformer."

The secondary has 3000 turns, so if I put 3V/turn to the primary, I get 9kV on the secondary, assuming sine wave driving and no resonance.

With a square wave, the peak output will be higher because of the ringing, but still if you don't run it at resonance, it can be nowhere near 83kV.

And just a last question, the 83 kV insulation rating is the breakdown voltage or working voltage? Does it assume the RF AC voltage (corona problems, etc) or is it just calculated from insulation thickness for DC voltage?

Thanks,
Jan

Re: Modern AC Flyback Transformers
Fiddy, Mon Oct 27 2014, 12:08AM


I see what you mean, it was designed for ZVS operation or flyback mode, i should probably put that on the rating.

83kVpk insulation rating is the breakdown voltage calculated by the manufacturer based on insulation thickness.

Re: Modern AC Flyback Transformers
Rod-on, Wed Oct 29 2014, 02:22AM

Mine arrived today, thanks mate.

Re: Modern AC Flyback Transformers
Artlav, Wed Oct 29 2014, 05:56AM

Hm?
That raises the question of why i haven't even got a PM yet.

Re: Modern AC Flyback Transformers
Fiddy, Wed Oct 29 2014, 08:55AM


Im getting there. you havent been forgotten! Im a single bloke who works 12 hour shift work so sometimes its hard to find the time.
I sent Rod on and mbd their's first because they are already in Australia.

Expect your PM soon!

Re: Modern AC Flyback Transformers
Artlav, Wed Oct 29 2014, 12:01PM

Sorry, didn't meant to sound like hurrying you up!

I just wondered if i missed something back then - no comments from anyone for a week and a half after you promised to start sending, then packages started arriving at the closest locations.

Re: Modern AC Flyback Transformers
mbd, Wed Oct 29 2014, 12:57PM

Well, I would just like to say a public thank you to Mitch.

And I'm confident that all of you in more distant locations will have your transformers sent soon.

MBD

Re: Modern AC Flyback Transformers
Artlav, Sat Nov 01 2014, 09:16PM

Hm.
I've been running some simulations of a typical ZVS driver with data from this transformer.

24V input, no load (500MOhm), 3V/turn primary.
When the thing starts, the voltage goes up to 53kV peak, before stabilising at 27kV 10ms later.
From ratio alone, you'd expect 24*(3000/8)=9kV, but you get several times that in ZVS.
Next notch up, 4V/turn, you get 68kVpk start-up and 37kV stable. Which is close to the limit already.
So, the warning appears to be valid.

No idea how correct the simulation is, but it matches up in the stable voltage part with another ZVS-driven AC flyback i have.

Re: Modern AC Flyback Transformers
dexter, Sat Nov 01 2014, 09:27PM

a ZVS works at resonance, the output is a sine wave... the volt per turn is higher by PI due to resonant rise
so your calculated 9kV gets multiplied by PI and that why you get 27-28kV

Re: Modern AC Flyback Transformers
Patrick, Sun Nov 02 2014, 03:59AM


If its rated for absolute 83kV, I would'nt let it get to 53kV for even for a few mS. Id put 100 to 50 Mohms on it, or at least something. (at 53kV your at 64% of breakdown.) 35 to 40 kV is more survivable.

High frequency seems to reduce insulation life as much as heat, but Ive looked for years to find something more than the typical 60Hz and 1kHz de-rating.

Re: Modern AC Flyback Transformers
Fiddy, Sun Nov 02 2014, 06:29AM

I was running mine today trying to figure out a suitable capacitor to impedance match the secondary, with a 24VDC on my ZVS with 10 turns on the primary of the flyback i was getting a peak of 74V across it.

Re: Modern AC Flyback Transformers
Fiddy, Mon Nov 03 2014, 06:55AM

Alex1M
Dragon64

Check your PM's, you are among the last 4 that haven't been shipped yet.

Mitch.

Re: Modern AC Flyback Transformers
Dragon64, Mon Nov 03 2014, 03:22PM


I sent you a PM (Oct 29) asking you about the pricing but didn't receive a reply yet.

Re: Modern AC Flyback Transformers
Fiddy, Mon Nov 03 2014, 03:36PM

PM Sent

Re: Modern AC Flyback Transformers
Ash Small, Wed Nov 05 2014, 12:43PM

I've been trying to pay using PayPal, but keep getting messages that you don't accept this type of payment. Has anyone else had any problems like this?

Re: Modern AC Flyback Transformers
Artlav, Wed Nov 05 2014, 01:24PM

I paid him by Paypal, without problems.
Maybe a typo or something wrong on your end?

Re: Modern AC Flyback Transformers
Ash Small, Wed Nov 05 2014, 07:34PM

Sorted.

Re: Modern AC Flyback Transformers
Fiddy, Thu Nov 06 2014, 08:39AM

all but 2 transformers have been sent! Good to see they are going to good homes

Re: Modern AC Flyback Transformers
Justin, Sat Nov 08 2014, 11:52AM

If you've still got one, please PM me a price.

Thanks

Re: Modern AC Flyback Transformers
Patrick, Sun Nov 09 2014, 06:52AM

Fiddy, did your maker give you a maximum voltage they could wind? or is it an insulation issue they calculate as the limiting factor?

Re: Modern AC Flyback Transformers
Rod-on, Tue Nov 11 2014, 12:32PM

I purchased two flybacks from Fiddy, fantastic they are. I have tried two drivers for them, a ZVS driver and a SMPSU driver.





Now for the question .... I want to use these to power a plasma tube similar to this one:




and I ask you, the experts (sadly I don't consider myself anything but an amateur) which one they would recommend I use.

Re: Modern AC Flyback Transformers
Ash Small, Tue Nov 11 2014, 12:41PM


I seem to be having problems with those links. Normally I can get round it, but not this time.

EDIT: Seems to be sorted now

Re: Modern AC Flyback Transformers
Fiddy, Tue Nov 11 2014, 01:20PM

Looks good Rod!

Try to keep the HV leads away from the core or it will arc over.

Re: Modern AC Flyback Transformers
Sigurthr, Tue Nov 11 2014, 01:25PM

Very nice results Rod-on! Do you have a link for that SMPS driver? I've never seen one like that. I've used cheap electronic fluoro ballasts for flybacks before with good results though, but often the wattage is too low for optimal results and the frequency is fixed usually far from resonance.

I'd not use ZVS for a plasma display just for safety and prevention of envelope punch through.

Re: Modern AC Flyback Transformers
TwirlyWhirly555, Tue Nov 11 2014, 02:12PM

Anyone run these on a half or full bridge yet ?

Re: Modern AC Flyback Transformers
hen918, Tue Nov 11 2014, 07:53PM

It's a bit scary that the HT lead does not insulate the high voltage! You would have thought they would have used tick enough insulation.

Re: Modern AC Flyback Transformers
Ash Small, Tue Nov 11 2014, 08:47PM

This can happen with any flyback when it's abused. One of the reasons why 'chicken sticks' are MANDATORY. Even in a CRT the HT lead has a plastic 'spacer' thingie to keep the lead away from grounded parts.

It shouldn't be too difficult to add extra insulation, but I'd still keep my distance.

I'm more concerned about internal breakdown, what with a 'theoretical' DC breakdown voltage of 83kV.

At least none of these have failed yet, but I'll probably destroy mine eventually, and cut it open to see exactly what's inside.

If you have concerns, run it under oil, with heavier insulated leads from the oil container to the arc, or other load.

Re: Modern AC Flyback Transformers
Rod-on, Tue Nov 11 2014, 10:57PM

I don't have a link or data sheet for the smpsu, I found a box of them dumped on the side of the road with a heap of wire and downlights. The unit is an "Electronic transformer for Halogen lamps dimable (trailing edge) and the stats on the unit are Pri 220 - 240v 50hz 0.25a pf>0.99 Sec12vac 20-60va max . Ta:0-40 deg c Tc 80 deg c.



and the guts of it:



I was surprised at the arcing over in the flyback, not only from the bolt to the cable in the video but also from the secondary to the frame (not captured on film) when I streched the arc to its maxium.
I put 10 winds on the primary, should I alter that?

I like the arc this makes better than the zvs (for my plasma tube project) ... we'll see

Re: Modern AC Flyback Transformers
Ash Small, Tue Nov 11 2014, 11:22PM

These halogen PSU's normally run at ~20kHz. Maybe it could be measured if it's not in the specs.

Is this it?

Re: Modern AC Flyback Transformers
Fiddy, Tue Nov 11 2014, 11:32PM


The leads are quite thick as they are, look at the volts coming out of the transformer, its really hard to insulate against that voltage when its really close or touching the core.

Re: Modern AC Flyback Transformers
Rod-on, Tue Nov 11 2014, 11:38PM

Yes Ash that's it

Re: Modern AC Flyback Transformers
Fiddy, Fri Nov 14 2014, 03:20AM

Hey guys i have one flyback left, it has a tiny bit of damage, one of the core supports has broken off, this certainly doesn't have any detrimental effects on the performance of the flyback, it actually allows the flyback core to swing 90 degree's to one side to be more compact.

See photos:





Anyway ill left it go for $45USD + postage, first in best dressed.

PM me if interested.

Re: Modern AC Flyback Transformers
..., Fri Nov 14 2014, 06:34AM

One of mine had some superficial damage on the bobbin as well, for some reason I have found shipping to/from australia to be by far the worst in terms of the packages being damaged. I ran a group buy ages ago and a sizable fraction of the packages arrived empty--the package had been torn open and all that arrived was the label!

Re: Modern AC Flyback Transformers
Fiddy, Fri Nov 14 2014, 06:56AM

Dam, i packed the cores with styrofoam on both sides then double wrapped the transformer in bubble wrap, then put them in a bubble wrap postage bag.

I do have spare bobbins, i dont know why they put a segmented piece on one end of the bobbin.

Re: Modern AC Flyback Transformers
MrCRC, Sat Apr 04 2015, 05:19AM

I would buy 1-2 of these flybacks. Are any still available, or is another manufacturing run planned?

Thanks!

Re: Modern AC Flyback Transformers
Fiddy, Sat Apr 04 2015, 02:48PM

There are a couple left it you are interested!

Re: Modern AC Flyback Transformers
MrCRC, Sun Apr 05 2015, 03:34AM


Ok, I'll buy one for now. Where to send $$$ ???

Re: Modern AC Flyback Transformers
Fiddy, Sun Apr 05 2015, 01:11PM

PM sent!

Re: Modern AC Flyback Transformers
woodchuck, Mon Apr 06 2015, 05:29PM

Fiddy, does this mean there is still one left?

I'd be happy to buy it. :)

Re: Modern AC Flyback Transformers
Fiddy, Thu Apr 16 2015, 04:36AM


Please read your PM's i dont have your address and its now listed on paypal!

Re: Modern AC Flyback Transformers
Kizmo, Sun May 17 2015, 08:23PM

Some time ago i got a hold of two of these transformers and finally decided to do something with them.

Basicly what i have is just igbt half bridge and Vco. Has anyone measured the self resonant frequency of the secondary coil? Mine peaks at 48kHz and the voltage rise is absolutely crazy. With 3 turn primary, and 12V input voltage to the half bridge (6V to load) i got corona fuzz from both HT leads and arc ignited about 50mm away

For normal arcing 25kHz seem to work ok. And 25kHz keeps my igbt brick happy too :)

Re: Modern AC Flyback Transformers
hen918, Sun May 17 2015, 08:29PM


You're driving these things with IGBT Bricks?! wow, should be able to push 'em hard!

Re: Modern AC Flyback Transformers
Kizmo, Sun May 17 2015, 08:42PM

Yeah, 200Amp 1200V half bridge brick. More than enough to set that poor thing on fire

Re: Modern AC Flyback Transformers
Fiddy, Sun May 17 2015, 09:38PM


pics and videos or it didnt happen!

Re: Modern AC Flyback Transformers
Kizmo, Mon May 18 2015, 06:56AM

It is most certainly not healthy for the transformer. Can i ground one end of the HT coil? Do you happen to know the internal construction, which HT lead is closer to the core or is this multiply pancake style HT coil?

Re: Modern AC Flyback Transformers
Fiddy, Mon May 18 2015, 07:02AM

You should probably put it in oil if your going to do that.

I don't see why you cant ground the secondary.

Im not sure on how they are wound but I have a blown secondary on one of the prototypes that i could dissect.

Re: Modern AC Flyback Transformers
Kizmo, Mon May 18 2015, 07:28AM

I would love to know. Grounding the inner end of the HT coil as well as core does wonders :)

Re: Modern AC Flyback Transformers
Kizmo, Mon May 18 2015, 09:52AM



Grounding either end of the HT coil did not improve the corona leakage between core and secondary so im pretty much maxed out voltage vise.

But if safety gap is used, nothing is really limiting the amount of power i can drive in

110VDC to the half bridge, 14turn primary and about 1kW of power (judging from variac vibration)

Re: Modern AC Flyback Transformers
TwirlyWhirly555, Mon May 18 2015, 11:54AM

Nice : D , Now go full bridge .

I run my Fullbridge for flybacks at 25Khz but its 30V @ 15A - 20A in , 30A peak in bridge .

Re: Modern AC Flyback Transformers
Kizmo, Mon May 18 2015, 12:04PM

No need for full bridge. The half bridge brick I use is 200Amp 1200V ultra fast semikron. If needed I can run this thing at 650VDC...

Re: Modern AC Flyback Transformers
Kizmo, Sat May 23 2015, 06:55PM



Damn these are tough! Meters are reading DC input voltage and current between rectifier and half bridge.

Re: Modern AC Flyback Transformers
hen918, Sat May 23 2015, 06:58PM

wow. I've seen MOTs give smaller arcs than that!
I'll have to design a good driver for mine

Re: Modern AC Flyback Transformers
Patrick, Sun May 24 2015, 04:09AM

kizmo, would you care to estimate the voltage from your above videos?

Re: Modern AC Flyback Transformers
Kizmo, Sun May 24 2015, 06:05AM

Voltage is limited to less than 10kV AC by the safety gap i use. Without said gap open circuit voltage would raise to 60kV AC and the poor flyback would get destroyed instantly.

Re: Modern AC Flyback Transformers
Patrick, Sun May 24 2015, 12:21PM

are you using 10mm then?

Re: Modern AC Flyback Transformers
Fiddy, Sun May 24 2015, 12:25PM

#####ATTENTION######

If anyone is still interested in these transformers or simply want more please let me know, the supplier keeps asking me to buy more, i can get them but I need numbers to it feasible.

Also if you have anything you would like to see in the transformer all opinions are gladly considered.

-Fiddy.

Re: Modern AC Flyback Transformers
Kizmo, Sun May 24 2015, 01:12PM

Count me in for 2 pieces.

Patrick: yes, about 10mm

Re: Modern AC Flyback Transformers
Erlend^SE, Sun May 24 2015, 03:46PM

There is actually a transformer manufacturer on the forum too.

Fiddy: how are your supplier regarding one off low volume stuff?

Re: Modern AC Flyback Transformers
Fiddy, Sun May 24 2015, 03:53PM


Noted, putting the new orders on the OP




Didnt know that. They can do low quantities but the postage can raise the overall price a quite a bit if I dont order many.
Are you interested?

Re: Modern AC Flyback Transformers
Erlend^SE, Sun May 24 2015, 05:43PM


Maybe earlier; now I have generic AC transformers and modern DC transformers(feedback resistor and grounded shield output cable) with normal and reversed polarity.

[Moderator edit: fixed broken quote]

Re: Modern AC Flyback Transformers
TwirlyWhirly555, Sun May 24 2015, 08:39PM

I'll be in for one .

Re: Modern AC Flyback Transformers
Fiddy, Mon May 25 2015, 03:13AM


is that a yes or no?



Sweet added to the OP

Re: Modern AC Flyback Transformers
Erlend^SE, Mon May 25 2015, 09:03AM

That would be a no thanks, I have what I need.

I am actually planning to sell off some of the transformers I have eventually.

Re: Modern AC Flyback Transformers
Fiddy, Sat May 30 2015, 08:45AM

Need to get the total units up to at least 20 before it becomes viable to put an order in with my manufacturer. only 16 to go :P

Re: Modern AC Flyback Transformers
Avi, Sat May 30 2015, 01:58PM

any option for one with 12v in (10A max), with at least 10kv output?

Re: Modern AC Flyback Transformers
GrantX, Sun May 31 2015, 05:38AM


They seem to be capable of much more than 10kV, and winding a primary coil for a 12V driver isn't an issue. There seems to be a nice large winding window, so its easy to change primaries quickly.

Fiddy, I'm interested in getting two transformers (kizmo's video of the extreme power-arcs persuaded me). I guess postage will be rather cheap since I'm in Melbourne.

Re: Modern AC Flyback Transformers
Fiddy, Sun May 31 2015, 07:15AM


As GrantX said, they run on 12V no worries and develop more than 10kV.

Shal i put your name down for one? two? 27? :P





Sweet GrantX ill add you to the OP, yeah would be $10 express id say

Re: Modern AC Flyback Transformers
Yuri_Ivanov, Mon Jun 01 2015, 12:57PM

I am the person Erlend mentioned before,and we are the manufactures of AC,DC,HV transformers,if you are interesting in bulding,we can discuss together

Re: Modern AC Flyback Transformers
Ash Small, Mon Jun 01 2015, 01:12PM


The only criticism I have of Fiddy's flybacks is that there is not much room to fit a primary UNDER the secondary. There is some room there and I'll see if I can fit a foil primary in there.

I think there is a market for AC flybacks with sufficient room for the primary UNDER the secondary. I'd buy some myself if they were available.

This SHOULD improve the characteristics of these flybacks considerably.

(Maybe there is sufficient insulation in Fiddy's flybacks to open up the hole in the secondary? Maybe ream it out a bit, but I've not tried this yet. Has anyone sawn one of Fiddy's secondaries in half yet?)

Re: Modern AC Flyback Transformers
woodchuck, Mon Jun 01 2015, 10:33PM

Fiddy, put me down for two!

Re: Modern AC Flyback Transformers
Fiddy, Tue Jun 02 2015, 06:13AM



My flybacks were designed for winding a primary underneath the secondary. I have a blown one here that i will cut in half soon.



Too easy dude, added tot he OP.

Re: Modern AC Flyback Transformers
Avi, Wed Jun 03 2015, 03:05AM

what is the maximum rated output voltage?

but
(10/13.2)*17=12.88 amps required for 10kv

27?! no!
somewhere between 0 and 1, depending on answers and things.

Re: Modern AC Flyback Transformers
Fiddy, Wed Jun 03 2015, 06:58AM


Ill put you down for one, k thx

Re: Modern AC Flyback Transformers
GrantX, Wed Jun 03 2015, 07:12AM

Avi, I believe the manufacturer stated a breakdown voltage of approx 80kV. Should be able to squeeze 20-30kV safely.

In your example you showed that it takes 17A at 22V on a 10 turn primary to create an ouput of 13.2kV and 28mA (approx 370VA), so a 5 turn primary would be a good starting point. Input current will vary, depending on switching frequency and the topology of your driver. You wanted an input of 12V at 10A, or 120VA, so you would be getting a short circuit current of 12mA with an open circuit voltage of 10kV.

These transformers should easily handle 120W at 10kV for hours, and Kizmo stuffed several kilowatts into his. What circuit do you intend to use as a driver? Do you have any specific frequency range in mind?

Re: Modern AC Flyback Transformers
Patrick, Wed Jun 03 2015, 07:19AM

i worry about claims of 120 watts and above based on some few mA at the short circuit voltage. I really wonder if the "real" voltage sags more than 10kv. I suppose im the one in a position to confirm or reject my suspicions.

I have the high voltage probe. a similar flyback, and would just need a load resistor that could handle 100+ watts for a few seconds.

Re: Modern AC Flyback Transformers
GrantX, Wed Jun 03 2015, 07:36AM


Indeed, accidently used Watts instead of apparent power in the last sentence. I was looking at it from a perspective similar to an NST: a 15kV 60mA unit will draw ~900VA on the primary side with the secondary shorted, but the secondary certainly isn't dissipating 900W of real power. W vs VA vs VAR can get very annoying, especially if someone changes units mid-paragraph without reason, sorry :)

Re: Modern AC Flyback Transformers
Avi, Wed Jun 03 2015, 07:47AM

mostly single mosfet drive (20Khz) but i do have a zvs board too (but i dont like it, its pretty hopeless for high voltage output with 12v input, mostly only good for high current output)

Re: Modern AC Flyback Transformers
GrantX, Wed Jun 03 2015, 08:19AM


Well, the last batch of customers seemed pleased with their transformers (hence why I'm buying some) and I think I saw a couple of videos of them driven in flyback mode. It would be a challenge to overheat the secondary with a 20kHz single-switch driver, but you would have to make sure the voltage spikes don't exceed ~20kV or so. A fixed safety gap is the easiest solution. The insulation between the core and secondary, as well as the HV leads, appears to be the limiting factor. I'm wondering if oil immersion could be used to increase the safe maximum voltage up towards 35-40kV.

Re: Modern AC Flyback Transformers
Patrick, Thu Jun 04 2015, 02:34AM

This is a different flyback, but could be a useful setup for others.



This is the back, yellow and black are the primary. The two green wires are a thermistor at the hotspot.







The 150 Megaohm resistors ensure at least some load to prevent uncontrolled voltage rise.



I use the original primary. With the advice from Proud Mary and some experimentation we moved away from the external one.

Re: Modern AC Flyback Transformers
DxrGregory, Thu Jun 04 2015, 10:24AM

I've done somethink like that but I think using FBT coil is bad idea. From one hand you have a coil with no work :) but on the other hand the FBT coil is very pure... low current, half wave rectifier and you must use low voltage at primary or many many turns on primary.

I would like to supply any projects from 230V stright from wall :) so I've made somethink like that:

1. Put of a core from FBT

2. Wire 50 turns at 8 sections on some pipe

3. make a input and output pin from screws

4. Sink in epidian

This transformer is driving by full bridge or half bridge and have very good parameters. I use this with voltage multiplier to have 80kV 10mA with no problems like overheating or breakdown voltage.

Sorry to my english...

Re: Modern AC Flyback Transformers
Yuri_Ivanov, Thu Jun 04 2015, 04:38PM

How baout built an AC 5-6KV 300W HV transformer? This is some pictures of our company manufacturing details

Re: Modern AC Flyback Transformers
Patrick, Thu Jun 04 2015, 09:16PM

lets not get to far off fiddy's topic, as Ash said, a foil primary may be the way to go. Al or Cu with a ultrathin plastic might get closer to the gap, but that raises local heating concerns with flux lines terminating on the nearest current path, not the whole width of the foil conductor. that gap can cuase this and other problems.

Re: Modern AC Flyback Transformers
Thomas W, Thu Jun 04 2015, 10:05PM

What is the price for 2 + uk shipping?

Re: Modern AC Flyback Transformers
Sigurthr, Fri Jun 05 2015, 12:50AM

For those who were worried about >100W extended runs:

I used mine to power a soft-failure HeNe Brewster tube that I repurposed as a decorative lamp. I ran it in parallel-tank-ZVS with I think about 5 turns at 14V 20A input. Tank measured something like 34Vpk @ ~270Apk circulating current. It ran for more than ten days continuous before the frit seals on the HeNe failed and the tube ruptured. Flyback and driver were unharmed.

Re: Modern AC Flyback Transformers
Ash Small, Fri Jun 05 2015, 12:56AM


Last time price for one plus shipping to UK was 84 US Dollars. Hope this helps.

Re: Modern AC Flyback Transformers
hen918, Fri Jun 05 2015, 01:15PM


Two transformers plus Postage to UK = $126 USD via Sea Mail or $148 USD via Air Mail.
That was last time, so it might have changed. I got two as well.

Re: Modern AC Flyback Transformers
Fiddy, Fri Jun 05 2015, 03:20PM


It will as hen918 said, shall i put you down for 2?

Re: Modern AC Flyback Transformers
Thomas W, Sat Jun 06 2015, 03:11PM

Yeh, why not, throw me down for 2 of them by air mail, as long as it comes to under £100, I'm cool.

Re: Modern AC Flyback Transformers
Fiddy, Sat Jun 06 2015, 04:27PM



Too easy added the the OP, should be under £100 for 2!

Re: Modern AC Flyback Transformers
Avi, Mon Jun 08 2015, 11:26PM

so $100 AUD each?

Re: Modern AC Flyback Transformers
hen918, Tue Jun 09 2015, 08:08PM

No, $50

Re: Modern AC Flyback Transformers
Avi, Tue Jun 09 2015, 10:39PM

£50 in aud

Re: Modern AC Flyback Transformers
Fiddy, Wed Jun 10 2015, 05:55AM


No, that was for 2 shipped to the UK

They are $50USD each + postage.

Re: Modern AC Flyback Transformers
Avi, Wed Jun 10 2015, 11:23AM

and how much is the postage to australia?

Re: Modern AC Flyback Transformers
Fiddy, Wed Jun 10 2015, 12:49PM

Im in NSW so $10 express

Re: Modern AC Flyback Transformers
StevenRS, Wed Jun 10 2015, 07:47PM

Hey, I'm in the US and you can put me down for four of the transformers. Been looking for something like this for AGES.

I'm guess that puts me at 200.00USD + 54.40USD

Re: Modern AC Flyback Transformers
Fiddy, Wed Jun 10 2015, 08:16PM


Certainly!

The postage will be either $50USD or $57USD for 4 transformers to the US, I cant remember the shipping weight of a transformer, (im at work atm)

Re: Modern AC Flyback Transformers
Avi, Wed Jun 10 2015, 11:50PM

oh ok

Re: Modern AC Flyback Transformers
Fiddy, Mon Jul 20 2015, 10:36AM

Hey dudes, i dissected my first sample transformer to see how she was wound, here are the photos:





We need 10x more people to put their name down for me to put an order in for another batch too.

Re: Modern AC Flyback Transformers
Ash Small, Mon Jul 20 2015, 12:45PM

Very interesting. Thanks for posting.

Re: Modern AC Flyback Transformers
Adam, Sun Aug 02 2015, 01:27AM

I'd be down for 4 to NZ

Re: Modern AC Flyback Transformers
Fiddy, Mon Aug 03 2015, 03:40AM


Sweet ill add you to the list!

Re: Modern AC Flyback Transformers
TecWizard, Mon Aug 10 2015, 09:36PM

Hello Fiddy

I am working on a project that needs to generate a plasma curtain. I have a prototype working with a ZVS and a TV flyback Transformer.
Will this transformer work when conntected to a ZVS with 5 to 8 turn center tap primary?

When would the next order of flyabacks arrive and ship to New York?

Would you give me the name of the supplier so I can go direct and order large volunmes (1500 to 2000 per year).

Thanks

Re: Modern AC Flyback Transformers
Fiddy, Mon Aug 10 2015, 11:02PM


Yes it will work with a ZVS with that center tap.

I will order the flybacks when i have 25 or more orders, im at 19 at the moment.

Can i put you down for some?

Re: Modern AC Flyback Transformers
LouisHV, Tue Aug 18 2015, 05:38PM

Hi Fiddy, gang :)

May I be rude and ask what the postage would be to Johannesburg South Africa for 4 flybacks?

If the postage is not too rough, I would like to commit.

Thanks!
Louis.

Re: Modern AC Flyback Transformers
Fiddy, Fri Aug 21 2015, 01:59AM


Hi Louis,

Each transformer is about 750g packed. so thats 3kg for 4 of them.

4x Transformers = 4 x $50 = $200USD

Postage = $86USD air mail or $44USD sea mail.

*Be aware sea mail can take up to 3 months delivery.

Total = $286USD or $244USD

Let me know if you are keen, i think you will be the last one that will allow me to put a order in with the supplier

Re: Modern AC Flyback Transformers
LouisHV, Sat Aug 22 2015, 03:56PM

Fiddy,

I'm in for airmail :)

I'll send you a PM for exchange of required details.

Thanks!
Louis.

Re: Modern AC Flyback Transformers
Green Hornet, Thu Aug 27 2015, 01:41PM

Just discovered this site. I have been winding HV AC transformers for over a year and wish to purchase two of these when next batch becomes available. Let me know when you want payment. (these are going to US).
I am retired EE and if you can provide me with core demensions and material I can give you back max primary voltage vs turns before sat and some air gap data. Your pic of core leads me to belive I have run mumbers on it if it is ASM7070 material. The reason I did not choose to use it is that was marginal for the power I needed so I have been usinbg larger cores. I have never had the patience to get much above 1000 turns, ( 7 ours work), so 3000 turns looks enticing. I will just have air gap it to keep it out of sat.

Re: Modern AC Flyback Transformers
Fiddy, Fri Aug 28 2015, 07:00AM


Too easy, I put you on the list.



Put you down for 2.

I dont know the ferite material but the core dimensions are in the attached photo.

Re: Modern AC Flyback Transformers
The NEYi, Fri Aug 28 2015, 02:50PM

Experimented with DIY flybacks a few years ago, just bought a pair of П-type ferrites and made my own windings. Results are below.



It outputs only about 3 kV, but because of huge currents the output is almost MOT-like. Also, no need in oil insulation.
The circuit is simple ZVS, but powered with 75V.

Re: Modern AC Flyback Transformers
Green Hornet, Wed Sept 09 2015, 04:00PM

This is a industry standasrd core size and I strongly suspect the materisal is ASTMP7070 which is the normasl for potted flybacks which would be normal for your supplier.
The industry standard specs for this 7070 material can be found at So here is a sample calculation using this xfrmr with the standard Mazilli ZVS with a .68uf tank capacitor.
The AL of this core is 2.3uh per Turn square. Choosing a primary of 10 Turns results in a primary inductance of 230uh and in the resonant Mazila Tank of .68uf results in a operating frequency of 13khz. BUT this is at 25 deg C. As core losses cause core temp to rise your AL will drop as will your max B sat. THis is why you want to run at 50kHz or less.

So using your cores cross section area, 10 turns, freq of 13khz, and a 50% margined Bsat of .25 Tesla x the 4.44 constant, yields a max VRMS across the primary of 461 VRMS. So an air gap should not be necessary to keep the core out of saturation with a DC supply up to 60V DC (remember this is a tank with a choke so VRMS accross ther tank will be approx 3- 4x the supply). If the core starts to heat up so it is "very warm" (50 deg c) to the touch,core losses will cause inductance will fall, frequency will rise, and Bsat will have fallen, which is why I used 50% of the mx Bsat of 7070 material in the formula.

The nnumbers say this should be a fine Xfrmer for use with a ZVS. You will want to use more than a 50-60 volt supply becasue the IRF260N FETs are rated at 200V and that is PK-Pk which is 1.4 x RMS which 3-4X your supply. I have made measurements with a scope accross the Mazilli tank and with a 30v supply the Pk-Pk at 50Khz is 180V, which results in each FET seeing 90V, or 50% of its max rating. DO NOT CONFUSE Pk-PK VOLTAGES WITH RMS and be aware of your instruments limitaions in measuring AC voltages over 20Khz.

Fiddy,
Looks like you have 25 Xfrms for next buy. When would you like $$$ frtom me? I am happy to pay early to helkp fund supplier if theuy want upfront

Re: Modern AC Flyback Transformers
Fiddy, Thu Sept 10 2015, 02:38PM

Ill be sending out emails very soon to see whos still keen, Green Hornet, what country you in?

Re: Modern AC Flyback Transformers
Fiddy, Sun Sept 13 2015, 07:55AM

PM's Sent!

Kizmo
GrantX
Avi
StevenRS
Adam

Please PM me or respond here if you would like to go ahead.

Re: Modern AC Flyback Transformers
Fiddy, Tue Sept 15 2015, 09:00AM

Update!
Transformers have been purchased, 1 week manufacturing then a couple days for delivery, then i should have them.

Will post a photo of what this batch looks like when i get one!

Stay tuned.

Re: Modern AC Flyback Transformers
GrantX, Fri Sept 18 2015, 09:13AM

Yay! Hopefully I wasn't too late in responding, I got buried in an avalanche of hobby-killing work and failed to see the new PM.

Re: Modern AC Flyback Transformers
Fiddy, Fri Sept 18 2015, 09:27AM

All good man!

Kizmo
Avi
StevenRS
Adam

Where you guys at?

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 21 2015, 10:48AM

Update

Trannys have been made and are on their way!

Re: Modern AC Flyback Transformers
Ash Small, Mon Sept 21 2015, 02:59PM

These look a lot better than the last lot, the HV outputs are in a much better position.

It should be a lot easier to get a foil primary in there, if required.

Re: Modern AC Flyback Transformers
Fiddy, Tue Sept 22 2015, 01:27AM

Thanks Ash,

To all others, if Kizmo,Avi,StevenRS and Adam dont reply by the time the transformers get here I will be selling their transformers off, first in best dressed.

Re: Modern AC Flyback Transformers
Green Hornet, Tue Sept 22 2015, 07:43PM

Fiddy, I am in USA. How Much do I owe you? What is your paypall address for payment

Re: Modern AC Flyback Transformers
Fiddy, Wed Sept 23 2015, 04:18AM


Hey man, Ill collect money after the transformers have arrived but for 2 transformers it wil be $100USD + 29 sea mail or 41 air mail.

Re: Modern AC Flyback Transformers
StevenRS, Sun Sept 27 2015, 06:08PM

Hey! I'm here, sorry gone for a little bit. Pm me the details and Ill throw money at you.

SO FREAKING EXCITED LIGHTING BOLTS INCOMING

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 28 2015, 05:00AM


Awesome Dude! Will do!

Re: Modern AC Flyback Transformers
Fiddy, Mon Sept 28 2015, 05:04AM

UPDATE

They have arrived ahead of schedule!

There are 20 spare bobbins let me know if you would like spares in your order.





Sending PMs about payment now.

-Fiddy.

Re: Modern AC Flyback Transformers
TwirlyWhirly555, Tue Sept 29 2015, 04:03PM

Guess its time to make a full bridge and push em ....

Re: Modern AC Flyback Transformers
StevenRS, Sat Oct 10 2015, 10:58PM

Whooooo excited about these guys. Going to see how they perform in my ZVS and then probably work on a full bridge type setup. My 12 stage multiplier needs moar current than my tiny little salvaged flyback can put out.

Re: Modern AC Flyback Transformers
Fiddy, Wed Oct 14 2015, 05:53AM

All Transformers have been sent, except for Kizmo and GrantX.

Re: Modern AC Flyback Transformers
Fiddy, Sun Nov 01 2015, 10:29AM

Kizmo isnt responding to any PM's im going to put his 2x transformers out there, is anyone keen on them?

Also i have 2x transformers from the 1st round i did, let me know if you would like any of them!

Re: Modern AC Flyback Transformers
woodchuck, Mon Nov 02 2015, 02:56AM

Even though I have two transformers from the new round, I am still interested in one from the first round. Are these largely unused?

Re: Modern AC Flyback Transformers
Fiddy, Mon Nov 02 2015, 03:31AM


Yeah never been used, they have sat around in the box.

Re: Modern AC Flyback Transformers
woodchuck, Mon Nov 02 2015, 04:23PM

Would you post or PM me the cost of one first-batch transformer plus shipping to the USA?

Re: Modern AC Flyback Transformers
Fiddy, Mon Nov 02 2015, 11:16PM

PM sent

Re: Modern AC Flyback Transformers
Kizmo, Sun Jan 24 2016, 11:07AM

Sweet little things. Cant wait to do something crazy with them :)

How about 4-stack? :D