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.
Introducing my first DRSSTC! My Flickr page has more photographs:
It's been a while since I posted anything here, but I just wanted to share my latest project over here. I've built a couple of SGTCs in the past, as well as a SSTC based on a half bridge of 60n60c2d1 minibrick IGBTs, and thought it would be a good idea to make my first DRSSTC. Here's a photo of it in action!
I'm in the process of doing a writeup right here:
As a learning experience, I wanted to go for something simple and nothing too fancy. I've had the fortune of being in the good company of other brilliant coilers (like Dr. Isotop here), and managed to get an older version of the oneTesla driver PCB, which runs this coil! I faced a couple of problems over the past few weeks but I've modified some parts and managed to get the coil working very well!
Important specifications including calcs from JavaTC:
- Max spark length - I don't know yet, does >20" sparks to free air and ground with ~100us on-time. More testing to come soon. - 222kHz resonant frequency (within 1%) - 2.4" Diameter PVC Secondary, ~2000 turns of AWG36 for a 10.25" length - 3.5" Diameter Acrylic Primary, 6 turns of AWG 14 for about 0.8" length - Single 0.101uF 2kVDC 942C CDE Primary Capacitor - 340VDC (120VAC rectified and doubled) - Roughly 100us on-time (in the photos here) - 2.2" x 8" AmazingOne spun toroid - Half Bridge of 60N65 IGBTs (seems to be similar to the 60N60 TO247 IGBTs) - Coupling = 0.22 - Energy Transfer time = 9.87us
Performance has been pretty good. I'm currently using an interrupter made by Dr. Isotop and Kramnik; the coil is controlled by the normal fiber-optics most other coilers use.
Originally, the coil used a 0.068uF 940C capacitor but that made my primary frequency about 19% too high and I lost a 60N60 half bridge. Increasing the primary to 8 turns of 14AWG (k=0.26) turned out to be a bad idea and I had a lot of racing sparks. After a few more coats of Polyurethane on the secondary, a return to 6 turns of AWG14 and a larger tank cap, the coil is in tune with a performance I'm very happy with.
This coil currently has a tiny built-in 19VDC laptop power supply for the electronics which uses the famed UCCs from TI as gate drivers to a GDT driving the gates of the IGBTs. More photos of the coil in action:
Would like to thank Dr. Isotop, Kramnik, and everyone else on the board for the valuable information and advice when building this coil. Right now I'm currently working on a newer coil using brick IGBTs (similar to CM150s).
Physics Junkie - That was definitely my SSTC then; the photos I've posted here were just taken within the past few days. I've had a bunch of problems with tuning and flashovers and finally got the right configuration!
RateReducer wrote ...
Very nice Coil and awesome photos! What settings are you you using on your camera? Exposure time, aperture...
The photos were taken using a 50mm lens set mostly at f2.8 IIRC. The exposure times etc don't really matter because it really depends on what frequency you're running the coil at. The coil (in these photos) were set up to play music via a MIDI Keyboard, so I just opened the shutter, played a few notes, and closed the shutter. ISO was between 800 and 1250, but it really depends on your coil and the surrounding brightness.
The photos here were taken with the coil running around 100us on-times. I tried to use a 'kill-a-watt' watt meter to measure power drawn but the meter goes crazy. I'd estimate that the coil draws about 500W, but again it depends greatly on on-time and bps.
I did a quick test to see how far the arcs would strick with a roughly 90us on-time and it seems to be able to comfortably do 21 inches as you can see in the photo below. The sparks are hitting a metal pipe, though it's sitting on a pushcart with rubber wheels so probably not a very good ground-strike test!
However, most of the sparks are simply hitting the concrete floor instead of going out, so I might need to do a different ground-strike test to find it's maximum spark length. For now, the 60N65 IGBTs seem to be holding up well!
Those really are great quality photos - good looking coil too. Have any video on youtube?
Thanks for your comments Bushman! Yes in fact I do have a short video. Note that the Tesla Coil was run at varying pulse widths (from about 110 to 60us), and was controlled via a midi keyboard + midi interrupter.
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.
A First DRSSTC - Just completed Table Top Coil!
