winding a sort of 2503 type output tranny . . . .

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strangeandbouncy

Well-known member
Joined
Aug 8, 2004
Messages
2,112
Location
West Sussex. UK
Dear All, - and, if I'm not taking the mickey, - Dear CJ, . . .


About a month ago or so, our noble CJ mentioned in a thread about op-amps(which I now can't find!) that it might be possible to wind your own 2503's . . . . I am deeply interested in winding some, or anything similar. 75:75:75:75 or even 150:150:150:150. I am not so much interested in necessarily making a perfect copy, more interested in making something that WORKS - to whatever degree! Sounds like a whole lotta fun to me. No matter how un-original/innacurate, sounds like a great way to start any kind of in-depth understanding of what-a-go-on-wiv-da-windy-windy-fings . . .

Am I alone in this? - Come on!


AndyP
 
Cosmo Corp has the bobbins
Mag Metals and many others carry the 625 I lams in M6
I tried Nickel, but M6 sounds better (bass response)
I am now looking for the quad Litz.
A little mylar tape and were done.

You can easily wind it by hand in about ten minutes.
Lead hookup about an hour.
No varnish required, just some Kapton or Mylar tape or a few brass bolts to hold the lams together and your done.

Color coded breakout wires would be very helpful, so if you want to source some 8 strand colorcoded cable, that would speed things along.

You sorce the bobbins by looking at the Cosmo Corp online catalog and picking the 625 EI lam number in the catalog itself. We only neeed one chamber. There will be about 4 or 5 one chamber models to choose from. Just choose the one they have in stock.
They will send four in a box as samples.

http://www.cosmocorp.com/index.cfm

xfmr bobbins w/o terms:

http://www.cosmocorp.com/cpintro-TB.cfm

pULLDOWN MENUS WILL SHOW 625 ei, WHICH YOU CLICK ON.
"the LAMINATION is:"
(sorry KURT!)
Note how many lams are in the catalog. Neve OPT takes a 75-EI square stack, if your interested in killing two birds with one sample shipment.

The API takes what's know as a "square stack", meaning that the core is stacked as thick as it is wide, so we want a 0.640 by 0.640 bobbin. Or 0.650 by 0.650 - give me some clearance, Clarence.

Height is 0.920.
Wall is around thirty thousandths.

If you click on the flange styles, a pic will show up. We coug use some grooves to push the wires thru, so a C, I, M, N, will work. Not critical.

When you see something you like, click on it and look for something in the upper left corner that hopefully says "Quick Ship Part? Yes!"

So after clicking on a zillion styles, you find a few that fit the bill.
And they ship Next Day, pal.

7036-0

This guy has no lead slots, but guess what, you can make your own. Drill hiles or slice grooves. Next day, and probably cheaper than the slotted. After all, this is DIY, right?

1214-0
 
dear CJ,

now that's what I call service! Awesome! I shall be ordering some bits n' bob(bins) forthwith. Me Likey!

Thank you so much for this information. I am sure that I am not the only one with this sentiment.

very excited indeed!

ANdyP :green: :green: :green:
 
I'm also interested in giving this a try. Thanks for the bobbin and lam info, CJ. I guess I'll have to get my *ss in gear and order some API pcbs from Mr. Bauman, too.

:guinness:
A P
 
I can get a "string" (read massive amount of lams) of 625 EI Microsil if you guys want and then pop them in the mail. Still working on the wire.

String:

string_1.jpg
 
As will be no surprise, this looks like we need to check who is interested and where they are & then combine stuff for people in the same area's of the world...
Nice developments, thanks !
 
Yeah, and this is not a gapped design, so no fine tuning to worry about, or sound changing because of gap problems.

We might even experiment with a bi filar design, two strands of reg wire wound at the same time, since who needs 4 windings. You could then get more turns due to less wire which reads more inductance which reads more bass and less strain on the op-amp ac current.

.
 
Hey, CJ, no need for mail here. We work within a few miles of each other best I can tell. If you get the lams I'll pay in your choice of currency ($$, :guinness: , :sam: , etc.)--perhaps over a big pile of lunch chow somewhere local. I'll be in for at least enough stuff for a pair of these, maybe four.

:thumb: :thumb: :thumb: :grin:

A P
 
Cool.
Sad thing is, I used to work at a transformer place. I had job pans full of M6 lams that were donated to me by the company. (old stock takes up space).

Anyway, the buckets weighed about 20 pounds a piece, but I never used them so into the trash they went. :shock:

Dang!

I am looking for a place near LA called Ram Sales. Acording to a winder friend, they sell all kinds of transfomer supplies, but I have not been able to get through to them. If anybody down south has a clue, ....
 
[quote author="CJ"]
I am looking for a place near LA called Ram Sales. Acording to a winder friend, they sell all kinds of transfomer supplies, but I have not been able to get through to them. If anybody down south has a clue, ....[/quote]

Found these on Excite's Yaller Pages:

Ram Sales & Distributing
14823 Aetna Street
Van Nuys, CA 91411
818-997-8057
Email: [email protected]

Ram Sales Inc
22865 Lockness Avenue
Torrance, CA 90501
phone: (310) 325-2955
Products & Services:
Electrical Equipment

Hope that helps...

A P
 
Yo
CJ

You are letting me down.

I know you know about
http://www.mwswire.com
They have quad filer wire. (They may have invented it)
I warn you to sit down before you get the price.
I think you need to get it in 10pound spools mininium.

It will be a pain to buy a large spool and cut it up for the masses.
But that is what we must do.

So let's do it a massive when I say massive
a nearly 1000 piece order for our favorite Xformer.
Then everyone will have the pieces siting around at home.

Those 280 turns can be done on a rainy day!

CJ please double check the orginal wire was AWG#31
 
> They have quadfilar wire. (They may have invented it)

They may have invented the non-DIY version.

Back in the stone age, we just hung four reels of standard magnet wire, held them together with our fingers, and started winding.

An alternative for low impedances is to pull 4 strands down the hallway, chuck one end in a drill, and twist to a single cable you can wind on the core.

A minor disadvantage is you have to use a buzzer to tell which end is which.

At VERY high quality level, such as Jensen, hand-winding or normal machine winding will not get a maximum number of turns (best bass for your core) or perfectly uniform lay (best super-treble).

But even a sloppy hand-wound bifilar or quadfilar will give better bandwidth than audio needs.
 
OK, I finally got a return message from

Ram Sales & Distributing
14823 Aetna Street
Van Nuys, CA 91411
818-997-8057
Email: [email protected]

They have all kinds of DIY transformer supplies, lams, mounting hardware, maybe even a winding machine now and then, so I will see if they have quad litz. Thanks Adrian for the link. The more sources for magnet wire, the better.

Thanks Analag for the links!

Only about 276 turns if I remember right on the API OPT, so about a ten minute hand winding job. The quad wire is big enough so that the turns will lay right down next to each other while hand winding.

cj
 
[quote author="CJ"]OK, I finally got a return message from

Ram Sales & Distributing
14823 Aetna Street
Van Nuys, CA 91411
818-997-8057
Email: [email protected]

They have all kinds of DIY transformer supplies, lams, mounting hardware, maybe even a winding machine now and then, so I will see if they have quad litz. Thanks Adrian for the link. The more sources for magnet wire, the better.

Thanks Analag for the links!

Only about 276 turns if I remember right on the API OPT, so about a ten minute hand winding job. The quad wire is big enough so that the turns will lay right down next to each other while hand winding.

cj[/quote]

Excellent! I realize you've probably still got "river brain" or something from the weekend, but it was a certain Mr. "Analog Packrat" <clears throat> who came up with the Ram Sales link. I believe "Analag" said something about needing cores (check), winders (two hands, check), and shellac (we don't need no steenkeeng shellac)...

:?

Analog Packrat
 
Wow, Guys!

Things are hottin' up, I see! I am floored by all this. SO DAMNED EXCITING for an ordinary shmo' like me. I would so love to be able to roll my own.



All the best,

ANdyP
 
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