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 #205
Joined: Sat Feb 18 2006, 11:59AM
Location: Skørping, Denmark
Posts: 741
All,
For a plasma globe project, I would like to use a Mazilli oscillator as driver of a B&W television flyback transformer.
Expertise tells me, that I must use around 5-20kHz into it for best results, but the Mazilli's that I have built resonate in the 60-90kHz range.
What determines the resonant frequency of a Mazilli?
I have found that by opening the core up a bit, thus lowering the inductance of the primary, the frequency goes up, so this seems to indicate that it is the primary inductance which determines the resonant frequency. Together with the capacitor across the primary. Is this right?
Also, can a flyback be driven below or under it's own resonant frequency?
Registered Member #152
Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384
I would not use the "zvs" driver for a plasma globe for two reasons: 1) the output current available is huge, you'll get big burns when you touch the globe. 2) this circuit inherently needs large amounts of reactive power circulating between the cap and core EVEN when the output is not loaded. This leads to high losses in the core and primary, which WILL get hot after some minutes.
Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
To echo what Harry said, the resonant frequiency is determined by the primary inductance and the resonant capacitor (the dc block inductor should not change the resonant freequiency). However, you must keep in mind that the primary is coupeled to the secondary, and the secondary's self capacitance--which is why the circuit likes to kind of lock onto a certain frequiency. With a commercial flyback you can't really change that, so your best bet is to use a large primary capacitor (I have heard as high as 10ufd being needed!) And living with the large circulating currents in the primary that will result.
One final note-do make sure that you have some way to limit the output current, the output of a circuit like this is quite lethal.
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.
Mazilli
