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 #61654
Joined: Fri Jun 16 2017, 01:13PM
Location:
Posts: 2
I recently finished my very first 270 VA NST SGTC, which has (thanks to the resources of this forum and the wider internet) been working a treat and delivering impressive 30cm sparks given its relatively feeble 9kV@30mA power supply. However, I believe I've messed up my RF isolation and grounding.
After my coil's first run on Sunday, everything in my house seemed to be fine - the TV and set top box worked as expected. However, less than 24 hours after first light, the STB cut to black unexpectedly in the middle of a program and the fan could be heard whirring at max power (i.e. unusually fast). After trying all the tricks to make it work, the STB would not recover and had to be replaced.
The bizzare thing is that the exact same thing happened to the replacement box, which has never been exposed to the coil. It was plugged in and worked normally for around 10 hours, before cutting to black and whirring like the last one. The box has no external PSU.
The Set-top boxes were given identical 4 connections:
Mains plug
Ethernet cable, connected to a powerline NP-511 ethernet-through-mains adapter
Street coaxial cable
HDMI to TV
The coil was only run once, which I'm assuming overloaded some protection feature that caused a delayed failure. My best guess is that it's EMI damage from the coil to the ethernet brick, but I wanted to ask a more knowledgeable forum for alternate theories.
My questions:
Has anyone here experienced similar issues? (Most coilers seem to work in their house/shed, close to mains wiring - what kind of filtering/protection do you use?)
How likely is it that replacing the ethernet adapter module will protect the third STB?
Will adding an auxiliary EMI filter before the variac fix (or at least reduce the severity of) the problem?
Please find a schematic attached below. A big part of the problem may have been my stupidly connecting the EMI filter too far from the mains socket, allowing RF to build up in the line.
Registered Member #30656
Joined: Tue Jul 30 2013, 02:40AM
Location: UK
Posts: 208
While I have killed an ethernet port when running a coil (actually half-killed, it now only works with certain devices, very weird), there is no way that anything should be at risk when the coil is off. Ethernet is isolated to at least 1500V, so even a faulty ethernet device at the other end of a cable should at most just not work - there is no reason or way for it to kill the rest of the device!
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.
SGTC (probably) broke my ethernet-over-mains unit. Help!
