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 #2318
Joined: Fri Aug 28 2009, 01:22AM
Location:
Posts: 33
Just wondering if this would be a good idea to try out if there is some reason this wouldn't work. I'm thinking of a 2" diameter secondary coil, with a 5 inch primary coil at its base, and instead of placing the feedback coil above or below the primary, actually putting it on a larger 6" form directly outside the primary. Has anyone here tried this before?
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
You raise an interesting point, Mr Duroo, because Nikolai Tesla designed a number of resonant RF HV transformers with quite different topologies, though today people usually only think of the vertical secondary with the primary wound around the bottom as being 'a Tesla coil.'
As for your specific question about the feedback winding, the coupling coefficient must be sufficient to deliver sufficient in-phase voltage to the grid to maintain oscillation.
Too little, and oscillation will die out; too much and the valve may 'squegg' - cyclically switch itself on and off at some quite low frequency, or it may enter some chaotic oscillatory mode whose nature we hardly dare guess at.
Registered Member #230
Joined: Tue Feb 21 2006, 08:01PM
Location: Gracefield lower Hutt
Posts: 284
This depends if you want to control with the primary parameters or the secondary parameters. magnetics tend to invoke the inverse cube law instead of the light and RF inverse square law
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
Proud Mary wrote ...
You raise an interesting point, Mr Duroo, because Nikolai Tesla designed a number of resonant RF HV transformers with quite different topologies, though today people usually only think of the vertical secondary with the primary wound around the bottom as being 'a Tesla coil.'
Briefly, a part of my career (?) included taking patents owned by my employer, and thinking up ways to break the patent so that my employer could patent those too, which makes me suspect that some of the patents (e.g. bi-filar primary) are more to exclude imitators than beneficial innovations, of little real value. (how many US patents for an improved or novel mousetrap ?)
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Oh yes, Tesla was very quick to patent, and I'm sure would have put up these anticipatory prophylactic blocks - I can't think what to call them! - as you suggest.
My knowledge of TC variants is really only what I can recall from enjoyable browsing of Victorian scientific illustrations and engineering drawings.
I recall one horizontal push-pull device where the centrally positioned primary was located inside the tube around which the secondary was wound.
When looking at antique apparatus and vintage experiments I always find myself hoping that perhaps the science had moved too fast, that the pressure to move on with new research was so great that potential avenues of discovery were overlooked and have remained undiscovered to this day - which I am sure must happen. Mostly I am envious of the simplicity of the equipment with which revolutionary discoveries were made in the early years of the last century, equipment so simple that even someone with only very modest abilities like myself could construct it with simple tools - the triode valve, Cockcroft & Walton's particle accelerator, X-ray crystallography, Wilson's cloud chamber, the radio telescope, the junction diode - and so on. But of course these illustrious thinkers had to think of these things first! :)
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.
Can the feedback and primary and secondary coils be nested in concentric circles in a vttc?
