The AM Forum
March 28, 2024, 03:56:17 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: Practical Transformer Winding  (Read 6541 times)
0 Members and 1 Guest are viewing this topic.
k4kyv
Contributing Member
Don
Member

Offline Offline

Posts: 10057



« on: October 18, 2011, 10:20:54 AM »

Even if you don't plan to wind or re-wind a transformer, here is some good information on how transformers are constructed, with plenty of photos. It doesn't cover the subject 100%, but is informative, especially for those who have never taken a transformer apart.

http://ludens.cl/Electron/trafos/trafos.html

He also has a link to another article on coils and transformers, but I don't think he is 100% correct on everything, particularly the section on DC chokes. He doesn't mention anything about gapping the core, and I question his statement that "... DC is simply a very, very low frequency... :-)" (like infinitely low, maybe?)

http://ludens.cl/Electron/Magnet.html





Logged

Don, K4KYV                                       AMI#5
Licensed since 1959 and not happy to be back on AM...    Never got off AM in the first place.

- - -
This message was typed using the DVORAK keyboard layout.
http://www.mwbrooks.com/dvorak
K5UJ
Contributing
Member
*
Offline Offline

Posts: 2845



WWW
« Reply #1 on: October 18, 2011, 01:35:35 PM »

Thanks don I did not know about that page.

Also if you scroll down here:

http://en.wikipedia.org/wiki/Transformer

There are diagrams on the right that show the way the coils are wound for the primary and secondary on an open EI core shell transformer.  Back last spring I realized that for me, transformers were another one of those black box type things i.e. I didn't really understand exactly how the coils were wound.  I found the wikipedia diagram under Windings helpful for a beginning understanding.

Rob
Logged

"Not taking crap or giving it is a pretty good lifestyle."--Frank
KM1H
Contributing
Member
*
Offline Offline

Posts: 3519



« Reply #2 on: October 18, 2011, 07:57:22 PM »

I wish I had all that info when I started rewinding in the late 50's! Too much trial and error and I got away from it.

Id like to do a big mod transformer but that would likely be a couple of stacked toroids. Too much black magic in the old methods.
Logged
Opcom
Patrick J. / KD5OEI
Contributing
Member
*
Offline Offline

Posts: 8308



WWW
« Reply #3 on: October 18, 2011, 08:12:27 PM »

It is the need for tooling, pretty much specially made up for the bobbin at hand, and the neatly layered wire when more than a few layers are needed, that has prevented me from trying transformers with more than a couple hundred turns.

It is very satisfying to wind one's own transformers, even if just small filament units. I never tried toroids due to having to figure out how to pass the entire spool of wire through, all were small EI cores where I saved the bobbins. Only three fil. units and one 140V unit for RTTY magnet power so far, I guess I am lazy and that is not a very good score for 40 years of experiments!

I'd like to see a home made toroidal mod transformer, that would be very cool! Do it!
Logged

Radio Candelstein - Flagship Station of the NRK Radio Network.
The Slab Bacon
Member

Offline Offline

Posts: 3934



« Reply #4 on: October 19, 2011, 09:26:30 AM »

Transformer winding may be a P.I.T.A., but the most miserable thing I EVER did was to rewind a magneto coil! ! ! ! ! ! ! ! ! (myself and a friend did 3 of them). They were for an American Bosch magneto for a 1 1/2 Hp early 1920s model Z Fairbanks-Morse gas engine. This was before they started making their own magnetos.

(apparently all of them failed from moisture)

Myself and a friend (who was deeply religious and didn't cuss) must have invented at least a dozen NEW cusswords winding those things. That hair fine wire is miserable to work with! But that was 35 years ago and mine is still working fine.
Logged

"No is not an answer and failure is not an option!"
WZ1M
Member

Offline Offline

Posts: 393


« Reply #5 on: October 19, 2011, 09:46:57 AM »

Talk about "MISERABLE", try winding 30,000 turns of #38 on a bobbin. Those interstage transformers are a real PITA. After you have the winding completed, now you have to attach leads to the tiny wire. Many a time it has broken off. and you have to start all over.
Regards,
Gary  Angry
Logged
The Slab Bacon
Member

Offline Offline

Posts: 3934



« Reply #6 on: October 19, 2011, 11:00:38 AM »

Talk about "MISERABLE", try winding 30,000 turns of #38 on a bobbin. Those interstage transformers are a real PITA. After you have the winding completed, now you have to attach leads to the tiny wire. Many a time it has broken off. and you have to start all over.
Regards,
Gary  Angry

Gary,
       at this point in my life, I dont think I would have the patience for that fine wire anymore. I would probably give it "flying lessons". (or send it to you) 30,000 turns sounds to me like chucking the bobbin in a lathe with the lathe backgeared.
Logged

"No is not an answer and failure is not an option!"
K9PNP
Member

Offline Offline

Posts: 476



« Reply #7 on: October 19, 2011, 01:04:35 PM »

He doesn't mention anything about gapping the core, and I question his statement that "... DC is simply a very, very low frequency... :-)" (like infinitely low, maybe?)

I guess he's one of those guys that looks at it as "approaching zero tangently".

Good post, Don.  Didn't realize how much I had forgotten or didn't know about the subject.  Thanks.
Logged

73,  Mitch

Since 1958. There still is nothing like tubes to keep your coffee warm in the shack.

Vulcan Theory of Troubleshooting:  Once you have eliminated the impossible, whatever remains, however improbable, must be the truth.
WZ1M
Member

Offline Offline

Posts: 393


« Reply #8 on: October 19, 2011, 02:31:44 PM »

Hey slab:
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.069 seconds with 19 queries.