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 #5193
Joined: Wed Jun 06 2012, 08:35PM
Location:
Posts: 1
A while back I built a pretty good (but small) tesla coil and recently have discovered the plasma speakers/singing arc. I decided to build a small prototype for experimenting. I modified Grenadier's plasma speaker circuit (ie adding DC blocking caps, totem pole stage to clean up the square wave and some other small mods) but the concept is the same. Without going into details, I am using 2 MOSFETs in a half bridge configuration to drive a flyback transformer. I am using a SG3525 IC for PWM from an audio source. I had it up and running last week and the music sounds great however I had a couple issues. When testing it i used a 12V power supply, the arc was good but quite small. The circuit is built to take a 24V DC input by the way. Anyways, I have a sneaking suspicion that the arc may be throwing off high levels of EMF. I am running it at about 30-50kHz. After about 5 minutes of listening to the arc within pretty close proximity I seem to get pretty bad headaches (Although it is just me, my friend who helped on this project says I am probably just sensitive to EMF or high pitched sounds or something ie. I can hear dog whistles pretty well). It doesn't last for more than an hour, but I thought it was pretty strange. Since then I haven't really used it too much. I am thinking about putting a faraday cage around it (made of some 2mm metal mesh) as I did with my tesla coil, but I'm not really sure if this would help at all.
Another problem was that when I hooked up my larger 24V power supply (regulated and multiple fuses - one at 6A and the other at 3A) the arc was much larger and louder. The power supply is modified from an industrial cooling unit (like an air conditioner but much more powerful). The power supply is rated for 24V @ 14A and I was drawing about 0.5-2A with the arc. But something very strange happened after I had it running for about a minute. All of a sudden my house power went out for about 5 seconds, no fuses in the house or in the power supply were tripped and I didn't see any massive voltage spikes. I have no idea why this would happen, but regardless the project has been put on hold until I figure out what is going on and how to remedy it. If anyone has any suggestions or could offer any advice that would be very much appreciated!
Registered Member #2919
Joined: Fri Jun 11 2010, 06:30PM
Location: Cambridge, MA
Posts: 652
Its exceedingly unlikely that the EMI is getting into your head and giving you headaches. You might be hearing the PWM frequency or other high-frequency components of the sound.
Registered Member #15
Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068
Make sure to use proper ventilation when running CW type coils. They produce a lot of ozone and other nitrogen based compounds which can be pretty nasty.
Also, if you are hearing audible noise, check your DC supply. Best check it with AC coupling on the scope and see if there is any ripple. If you have lots of ripple, you are likely to be hearing that as hissing or audible hum depending on the magnitude / frequency.
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.
Plasma Speaker Problems
