Transformer parts

Hi

Can anyone reccomend an Australian supplier of transformer parts (laminations, bobbins, frames, end bells etc) suitable for valve output stages ?

Many thanks in advance

Steve Andrew

Reply to
Steve Andrew
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"Steve Andrew"

** Here is one in SA.

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....... Phil

Reply to
Phil Allison

Just a cautionary note. Creating good quality transformers yourself is no mean feat. The construction has to be very precise, in terms of gaps and compactness of windings, selection of wire gauges and in the case of audio, core design and material (many suppliers cater only for the mains market at

50 Hz). And you don't find out how well you've done until the job's finished, if there are problems it's a matter of more or less starting again.

The other aspect you might want to consider with valve audio is safety. With the primary running at several hundred volts DC with a fair size capacitor behind it, any failure in the interwinding insulation could result in a serious hazard. At very least, it would be worth finding out what you can about insulation techniques and standards.

Good luck and you'll certainly learn a lot, but getting a premade item is likely to save you a lot of time and trouble, even if it costs somewhat more.

Reply to
bruce varley

"bruce varley"

** Like these nice Canadian made "Hammond" ones from EVATCO:

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....... Phil

Reply to
Phil Allison

AEM cores in Sth Aust don't make E&I lams or Ccores anymore. The do have unicores but they are not suitable for tube amps either in the power or output transformers. I have tried them. The cores are excellent in power trannies where no rectification occurs. Losses are the same as toriodal cores of spiral GOSS strip. Unicores are difficult to restrain and hold in place.

Sankey of Newcastle NSW do make excellent quality GOSS E&I cores but you have to buy a minimum order of 50Kg paid in advance at about $13.20 per Kg including gst. This material is imported and Sankey stamp out the E&I in various shapes and size to order and then aneal it and the maximum permeability when fully intermeshed is

17,000. Its the best material for PP or SE OPTs, although I have not tried GOSS with 50% nickel laminations. I have no clue where nickel cores could be bought; there is no demand in a tiny country like Oz.

Bell ends yokes and plastic bobbins are maybe still available fron Engineering Enterprizes in Melbourne. Not all sizes are available and the bell end finish is lousy since they are stamped on machines no maybe 60 years old.

Grade 2 polyester-imide dual coated enamel hi-temp wire and varnish and mylar insulation materials can be obtained from Blackburn Wires in Sydney.

I often make my own bobbins with fibreglass sheet and electrical grade board.

There is also a supplier in Oz for Eilor C-cores from Isreal; maybe you wait for the parts to arrive though.

Patrick Turner

Reply to
Patrick Turner

"Patrick Turner"

** Proves nothing.

Turner is a demented, criminal imbecile.

........ Phil

Reply to
Phil Allison

I've tried them also, you s***ma scraping, toroidal obsessing, dickwad. They don't sell them any more and didn't want to sell mu-metal either.

Reply to
Mark Harriss

Nobody will believe you Phil.

The full text you should have quoted but didn't was :-

Phil Allis> "Steve Andrew"

Now Phil, let me make the point again, and more firmly, and that it is that you directed someone interested in tube amp parts to AEM, but they would be unable to be of much help.

They were of help until about 5 years ago when one could order C-cores made to order, but not any more. They have not made E&I lams for many years. Although AEM's Unicores are a great idea there are problems using them to gain a product that looks as good as the E&I lams with bell ends. Then there is the problem of mechanical clamping of them; they rely more vanishing, and are more difficult to clamp than C-cores or E&I, so waxing them like many DIYers do with OPT would not be good practice.

The Unicores are however available in various forms with regard to gaps which can be stepped or partially formed and a clever designer would perhaps be able to use them to advantage, but I have never seen any Unicored OPT yet. When fully and maximally intermeshed the unicores have virtually the same permeability as a toroidal wound with GOSS and are thus prone to dc saturation at low levels due to net dc imbalance in PP output stages. One advantage is that the unlike wasteless pattern E&I lams, the window size can be made larger in respect to the Afe, ie, the area of the build up and strip width going through the coil, so the Acu can be a lot higher to make the OPT have very low copper losses, a useful thing in an OPT. Of course the same rules apply with the Afe and saturation and you still have to design the unicored OPT able to have B= 1.6T at 14 Hz. Good OPTs with wide bandwidth are always going to be heavy with respect to the VA rating.

I am a not a demented criminal imbecile for offering the public the wealth of my technical experience.

But we all know who the demented imbecile really is, and he's never wound an OPT afaik.

Patrick Turner.

Reply to
Patrick Turner

: > Turner is a demented, criminal imbecile. : >

: > ........ Phil : : Nobody will believe you Phil. : : : Patrick Turner. : : Sorry to correct you Pat but apparently something called an Andre Jute does and he believes everything Philthy posts. From AJ's posts today I gather Philthy and he are betrothed ;-)

Cheers TT

Reply to
TT

Terry, where are Jute's posts? Apart from the one quoted by Patrick (which doesn't read like Jute anyway) I can't find them. I smell a rat here.

Reply to
paul packer

You would need excellent bullshit filters for sure.

Patrick Turner.

Reply to
Patrick Turner

by Patrick

smell a rat

The thread "Scum that make me ashamed to be an Australian" by Andre Jute. He attacks several of the good guys ;-) It is so Monty Pythonesque it is funny actually and I have been accused of a *Taunting*. A passing acquaintance of Python's Holy Grail is must here :-)

Cheers TT

--------------------------------------------------- Andre Jute wrote to Philip Allison:

"> Congratulations on proving once again that you are a more useful member

audiophile) than

necessary after

possibility that

sort of

I used to be tough on the cultural cringers and others who apologized for being Australian. But now I understand how they feel, after I saw TT ( snipped-for-privacy@westnet.com.au) and Alan Rutlidge (don't_spam_me snipped-for-privacy@iinet.net.au) and the rest of that aus.hi-fi trailer park trash (1) in action, taunting Phil, then complaining that he abuses them. They should be abused, indeed stepped on hard enough to wipe them. They're bullying scum.

Andre Jute Zero tolerance for farmyard bullies

(1) And in more moral times, that British loudmouth Mark Harriss ( snipped-for-privacy@blartco.co.uk) would have been deported to father more criminal progeny like TT and Rutlidge, on sheep of course.

----------------------------------------------------

Reply to
TT

Years ago (decades actually :( ), I had a very nice set of nomographs, published as I recall by the then Wireless World. A great number of the nomographs covered various aspects of transformer design which I used with good results. I made the error of lending them to somebody who managed to lose them. I guess it's a case of getting the older books out, along with my trusy old guessing stick (slide rule) and starting from scratch.

Point taken. I made many HT transformers in the early 70's and learned the hard way, with a home-made choke just what happens when poor quality insulation breaks down.

If I could get something like Hammond transformers in Oz, at a similar price to those charged in the USA and Canada I would not hesitate to do so. I may well go that route. I'm curious at this stage to see just how much cheaper a good quiality audio transformer can be 'hand rolled', as opposed to paying the grossly inflated prices for an imported item. I have time on my hands so I'm not worried about the time taken to wind them.

Thanks again for your input.

Reply to
Steve Andrew

Nice maybe, but I object to paying nearly twice the US$ price :(

Type 1645 in USA (according to Hammond catalogue) retails for around US$65, the part here retails for around AU$161, the US price is around AU$89. I'm sure there is *some* justification for this byt nearly *twice* the price ?

Anyway Phil, thanks for the link. If all else fails (it usually does :) ) I'll have to grit my teeth and shell out the extra.

Reply to
Steve Andrew

"Steve Andrew"

** Then you are a foolish tight wad.
** A fantastically cheap price to begin with.

You have no idea.

** The reasons are simple:

Freight, insurance, import & handling costs, storage, low sales volume, dead stock....

The $ price ratio is only 1.8 times - lower than for most *US made* products sold in Australia.

** EVATCO has some cheaper valve output transformers ( made in Asia I expect) so why not call Arthur and see what the situation is.

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....... Phil

Reply to
Phil Allison

"Steve Andrew" wrote in news:8rW4g.19356$vy1.5957 @news-server.bigpond.net.au:

In Melbourne (dandenong) you can probably get most of this stuff from Southern Electronic Services. They do manufacture O/P trannies. They will probably supply parts if you ask Scott nicely. Their designs are conservative and will last a lifetime.

Reply to
Geoff C

We were hoping you'd be just the person to help with that process.

Sorry you couldn't see your way around the HTML at

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Patrick. You'd still be very, very welcome there.

Reply to
Ayn Marx

process.

I'll second that :-)

Cheers TT

Reply to
TT

You'll have to add a "tube/valve audio" section first, before Patrick will bother to look ;-)

BTW is this board exclusively for Aussies, or is participation from other parts of the world welcome as well?

--
- Never argue with idiots, they drag you down their level and beat you with
experience. -
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Reply to
Sander deWaal

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