If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
When I want a nice straight piece of copper wire I clamp one end and pull on the other untill I feel it stretch a little, then it's VERY straight. I've tried it with insulated galvanised iron wire (gardening dept.) for a small induction coil and vlf antenna. it works with iron too. Getting all the strands tightly packed needs a little effort, especially the cut ends are a nuisance. Cut the wires longer than required, starting at the middle of the bundle wrap with nylon fishing thread to one end, then from the centre to the other end. Then stuff the bundle into a tube unwiding the fishing line as you go. A little glue or varnish to solidify the assembly, then saw off the ends for a neat finish.
I have a couple of about 1" dia x 15" long bundles in pvc or Tufnol tubes that I tried. Not worth the effort compared to ferrite.
Registered Member #3414
Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
Sulaiman wrote ...
When I want a nice straight piece of copper wire I clamp one end and pull on the other untill I feel it stretch a little, then it's VERY straight. I've tried it with insulated galvanised iron wire (gardening dept.) for a small induction coil and vlf antenna. it works with iron too. Getting all the strands tightly packed needs a little effort, especially the cut ends are a nuisance. Cut the wires longer than required, starting at the middle of the bundle wrap with nylon fishing thread to one end, then from the centre to the other end. Then stuff the bundle into a tube unwiding the fishing line as you go. A little glue or varnish to solidify the assembly, then saw off the ends for a neat finish.
I have a couple of about 1" dia x 15" long bundles in pvc or Tufnol tubes that I tried. Not worth the effort compared to ferrite.
If you 'stretch' the wire, won't it require re-annealing before use?
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Sulaiman wrote ...
When I want a nice straight piece of copper wire I clamp one end and pull on the other untill I feel it stretch a little, then it's VERY straight. I've tried it with insulated galvanised iron wire (gardening dept.) for a small induction coil and vlf antenna. it works with iron too. Getting all the strands tightly packed needs a little effort, especially the cut ends are a nuisance. Cut the wires longer than required, starting at the middle of the bundle wrap with nylon fishing thread to one end, then from the centre to the other end. Then stuff the bundle into a tube unwiding the fishing line as you go. A little glue or varnish to solidify the assembly, then saw off the ends for a neat finish.
I have a couple of about 1" dia x 15" long bundles in pvc or Tufnol tubes that I tried. Not worth the effort compared to ferrite.
Thanks for that, and I note your caveat at the end. Ash also asks an interesting question on annealing.
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
If you look at Fig.3 of this document ,d.bGQ you will see why very large permeabilities are not required.
As for annealing ... I never even considered it !
P.S. I've tried a bundle of 7x ferrite rods, multiple rods in series, turns spacing, Litz wire etc. They all improve 'Q' etc. but the gain compared to a single layer of 'magnet wire' for all of the options is not proportionate to increased cost/complexity.
As for the original question; " if you have a transformer with copper primary and iron secondary's, at high hertz, what would the effect of the wave form be as iron has some retention " I would expect the waveform to be the same as if made with copper wire BUT higher frequencies/harmonics will be attenuated much more than with copper due to 'skin' and 'eddy' effects.
Registered Member #3414
Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
The example in the link above was for 'hedgehog' (or 'hegehog') interstage transformers for audio wavelengths, Sulaiman, with the wires wrapped around the outside of the windings. I believe, in this case, that permeability is an issue, in order to avoid saturation, especially at low frequencies.
What you say may be relevamnt for antennas, but I don't think it applies in this case. Maybe I've missed something, though?
Registered Member #4266
Joined: Fri Dec 16 2011, 03:15AM
Location:
Posts: 874
If you 'stretch' the wire, won't it require re-annealing before use?
, The resistance will be lower if its not annealed, and I think the permeability is increased if brittle.
If you have a voltage across a inductor(it just magically appears), what formula would you use for current. T = L/R A = V*L/Sec or (A=V/L/Sec) X = 2pie*f*L A = V/R
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
I = (V/X) + (V/Z)
I = current in winding V = voltage across winding X = 2.PI.F.L = inductive impedance of winding F = frequency L = inductance of winding Z = impedance of any connected load
Registered Member #3414
Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
I'm certain that silicon steel and other soft magnetic alloys require annealing, as, as far as I'm aware, if it is work hardened, the structure turns from ferritic to martensitic, which is a hard magnet, however, I'm eager to learn, if you have any relevant links.
Registered Member #4266
Joined: Fri Dec 16 2011, 03:15AM
Location:
Posts: 874
The book was called electricity for the trades volume 6, it just said that resistance is less for hard copper than soft etc, about the magnetic material, will have to double check it might be retention not permeability.
Thanks Sulaiman, I'm getting really low values for amps, if a resistor is in place after the coil or the coil had high resistance, would that effect the X in the formula or be part of Z.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Ash, you'll love this book - which specifies very soft annealed iron wire for cores: Induction Coils: A Practical Manual for Amateur Coil-Makers, by G.E. Bonney, London and New York, 1904.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
Copper wire primary and Iron wire secondary,what type of wave form will the transfomer have
