For the beginners ? here a bit of electronics theory

Agree about volts per turn but the HV winding has worse load regulation than the tight windings

piglet

Except that it does. Mostly not a lot, because you don't change the coupling all that much, but it is the changing flux going through the coil that generates the voltage, and the leakage inductance is the flux that doesn't go through that coil.

On a sunny day (Mon, 10 Oct 2022 09:30:09 -0700) it happened John Larkin snipped-for-privacy@highlandSNIPMEtechnology.com wrote in snipped-for-privacy@4ax.com:

Indeed!!! I got email from my US website hosting company 'godaddy' that as of tomorrow they no longer support pop email, and move every email related thing to Microsoft, as 'everybody has a smartphone anyways'. I phoned them, after 3 attempts I got a real person on the line he told me it was for 'security reasons'... Well Linux has done better at that .., and no pop email makes life difficult as everything is automatically scripted and organized here. Told the guy tell your boss I do not like it. Just found a local web hosting company and will be moving everything there, Godaddy sucks now. There will probably be a 'panteltje.net' for test and if that works OK I will move panteltje,com there too. So, an other US company shoots itself in the foot, loses me as customer after 25 years!!! by going Microsoft.

Sometimes I prefer to show parasitics, like series resistances or leakage inductances, as components in plain sight. Sometimes a value in uH is more meaningful than a K, like in your case of a complex transformer.

Sloman doesn't approve because he always follows rules, and doesn't design real electronics.

We don't know what Jan's posted image represents. It's not LT Spice.

D1-C1 in Jan's schematic is interesting, as opposed to just using the autotransformer and saving parts and diode drops.

But leakage inductance does.

I'd guess that the old TV flyback transformers had a bunch of leakage L. They sure skimped on ferrite.

Mouser could sell leakage inductors, back-ordered to September 2023.

You need leakage inductance in a flyback. Most of the energy is stored in the air gap.

Cheers

Phil Hobbs

There's the right way, the wrong way, and the Microsoft way. Microsoft bets on a perpetual population of lazy-bones users.

The name "GoDaddy" said it all to me back in the day after it popped up out of nowhere. The name of my own provider, "QTH," says it all to me too, but it says different things. You might want to take a look at my provider, qth.com. It's very Linux friendly as its name suggests. Needless to say, the guy behind it is a ham.

Danke,

Sure, the energy is mostly in the air gap, but it's not in the leakage inductance! You could have near-complete flux coupling *with* an air gap. The energy is still mostly in that gap.

Jeroen Belleman

I like the DRQ series of dual-winding inductors. They are bifalar wound with air gaps, K typically 0.992.

I measured winding-winding breakdown at 2250 volts.

Phil Hobbs snipped-for-privacy@electrooptical.net wrote in news: snipped-for-privacy@electrooptical.net:

In "the core" as a result of "the air gap".

On a sunny day (Wed, 12 Oct 2022 15:12:01 -0000 (UTC)) it happened "Don" snipped-for-privacy@crcomp.net wrote in snipped-for-privacy@crcomp.net:

Thank you very much, simple and logical list of options on qth.com! I will check it out, probably ask them a few things.

The two aren't identical, but they're sure related.

Cheers

Phil Hobbs

Nope, in the air gap itself.

Cheers

Phil Hobbs

Not forgetting that in ferrite cores the air gap is distributed inside the core as part of the ferrite mix.

piglet

Depends. A TV flyback runs at the horizontal scan frequency (15750 Hz or thereabouts), so core losses are less of an issue.

Cheers

Phil Hobbs

Fastmail is an excellent email provider.

A bizarre misrepresentation , though it is probably merely an incompetent insult. You don't get your name on patents by following the rules, and if you want to get your circuits published in the peer-reviewed literature they'd better be real and unexpected. John Larkin wouldn't know about that - he has got his name on one patent because the people he was working with needed to flatter him, and he doesn't publish in the peer-reviewed literature.

It's scrawled circuit diagram. You'd need to redraw it to make any sense of it, and what's been left out probably means that you wouldn't duplicate what Jan put together. The components mostly aren't numbered.

That's not really the right way to think about it.

You can store more energy in a gapped inductor, because the inductance drops and the saturation current rises in proportion to the gap, but the energy stored is proportional to the square of the current.

You can't make the gap too big or the turns don't have enough mutual inductance to couple to a useful extent.