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 #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Microwatt wrote ...
I have a project where I need 1-3mhz at 10kv volts only a few ma is needed. anybody got any ideas on how to make?
The interval 300kHz - 3Mhz is known as Medium Frequency (MF), and not 'very high frequency' (VHF) which designates 30MHz - 300MHz.
A very simple MF transmitter circuit will meet your needs:
Variable Frequency Oscillator (VFO) Buffer Amplifier Power Amplifier Pi-network output matching circuit
The high voltage can be produced from the output by means of an RF transformer.
You can make it as simple or as a complex as you like - a bare bones VFO with a variable capacitor and a front panel dial, or full digital frequency synthesis with an LCD read out and auto PA tune and match.
Registered Member #2919
Joined: Fri Jun 11 2010, 06:30PM
Location: Cambridge, MA
Posts: 652
1 MHz is within the range of standard switchmode fets, especially at such low powers. In fact, 3 MHz is probably still fine, though obtaining your gate drive signal will be tricky.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
bwang wrote ...
1 MHz is within the range of standard switchmode fets, especially at such low powers. In fact, 3 MHz is probably still fine, though obtaining your gate drive signal will be tricky.
A much better idea than my single active device power oscillator suggestion.
Registered Member #3429
Joined: Sun Nov 21 2010, 02:04AM
Location: Minnesota, USA
Posts: 288
HighVoltageChick wrote ...
I am not sure if this is possible but modify a plasma globe to get that?
A Jacob's Ladder that runs off of a NST produces a much hotter and longer arc than you would be able to get from a "modified plasma globe". If you want a "real" Jacob's Ladder, then I would suggest buying an NST. If you want a small (wimpy) Jacob's Ladder, then you can make one with a couple of 2N3055 power transistors and a modified flyback transformer. There are schematic diagrams for that circuit on 4hv and also all over the web (it's very simple and popular).
I truly believe that you would be wasting your time attempting to modify a plasma globe to work as a Jacob's Ladder. If you can afford it, buy the right parts and build something that you will be proud to show off! If you cannot afford new parts (and many people can't) you should be able to find used parts from guys here on 4hv or from Grenadier's "Junk Box" here:
Registered Member #3900
Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
If you want a "real" Jacob's Ladder, then I would suggest buying an NST.
who says he wants a "real Jacobs" ladder? or even a Jacobs ladder at all? all he said is that he needed a 1-3Mhz 10kV supply for his experiments. a Jacobs ladder isn't really an experiment, its just a display of your arc. you are right, a 60hz mains driven iron core transformer gives a nice hot arc, but that isn't necessarily what he wants.
and Microwatt, for us to help you any further than we have, it would help to know what you are trying to do.
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.
High voltage very high frequency
