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Main, Kerry
*nix forums Guru
Joined: 22 Jul 2005
Posts: 399
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 Posted: Tue Jul 18, 2006 10:50 am Post subject:
RE: http://h71000.www7.hp.com/?
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| Quote: | -----Original Message-----
From: JF Mezei [mailto:jfmezei.spamnot@teksavvy.com]
Sent: July 17, 2006 9:46 PM
To: Info-VAX@Mvb.Saic.Com
Subject: Re: http://h71000.www7.hp.com/?
Dave Froble wrote:
Like you, I use ping to determine connectivity. I totally
understand
why it's disabled, but it sure is a pain in the ass.
If HP's network were not "blocked", we would have been able
to see that
traffic stopped before the VMS node and perhaps send an email to some
netowrk administrator that should be there 7/24. As it stands, we all
tended to blame the VMS node itself.
|
That is the job of those being paid to manage stuff like this. Some
monitoring processes in place did not work as expected and from what I
have heard, steps are being taken to address this.
If HP or any other business had to rely on a Cust notifying them of an
IT failure, then that would be a very poor IT infrastructure.
| Quote: | What it does show however is that no matter how disaster tolerant VMS
might be, if it is connected to the net by a single switch, then it
becomes quite vulnerable to downtime.
|
Mmm .. Kind of why we stress DT solutions - not just DT systems.
Same applies for single server or single site as well.
Regards
Kerry Main
Senior Consultant
HP Services Canada
Voice: 613-592-4660
Fax: 613-591-4477
kerryDOTmainAThpDOTcom
(remove the DOT's and AT)
OpenVMS - the secure, multi-site OS that just works. |
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etmsreec@yahoo.co.uk
*nix forums addict
Joined: 27 Jan 2006
Posts: 95
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| Posted: Tue Jul 18, 2006 12:38 pm Post subject:
Re: http://h71000.www7.hp.com/?
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And if the HP network were not "blocked", they would have every windows
weenie between here and the other side of the world exploring their
network and figuring out every little hole that they could.
Companies like HP keep their servers hidden for a good reason. Just
like you and me, they don't like downtime.
Steve
JF Mezei wrote:
| Quote: | Dave Froble wrote:
Like you, I use ping to determine connectivity. I totally understand
why it's disabled, but it sure is a pain in the ass.
If HP's network were not "blocked", we would have been able to see that
traffic stopped before the VMS node and perhaps send an email to some
netowrk administrator that should be there 7/24. As it stands, we all
tended to blame the VMS node itself.
What it does show however is that no matter how disaster tolerant VMS
might be, if it is connected to the net by a single switch, then it
becomes quite vulnerable to downtime. |
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Bob Koehler
*nix forums Guru
Joined: 25 Jul 2005
Posts: 1078
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| Posted: Tue Jul 18, 2006 12:39 pm Post subject:
Re: http://h71000.www7.hp.com/?
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In article <51Sug.624$Ir3.562@news.cpqcorp.net>, Hoff Hoffman <hoff-remove-this@hp.com> writes:
| Quote: | Bob Koehler wrote:
While I'm not at all sure that HP still runs that site under VMS,
The OpenVMS external web site runs on OpenVMS Alpha.
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That's good to know. |
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JF Mezei
*nix forums Guru
Joined: 21 Jul 2005
Posts: 2556
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| Posted: Tue Jul 18, 2006 7:15 pm Post subject:
Re: http://h71000.www7.hp.com/?
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w_tom wrote:
| Quote: | EMP is so trivial that even an NE-2 neon glow lamp (a bulb rated in
milliamps) will make such transients irrelevant. If a transient
overwhelmed protection already inside appliances, this it was not EMP.
It was a direct strike.
|
This is not as simple. In the 1980s, much of quebec was thrown into
darkness because of aurora borealis a few thousand km north of montreal.
Those induced currents into the power lines from james bay and
protective circuits automatically shut then down and Hydro Québec's
software was ill conceived to automatically start load shedding and as a
result crashed everything. (our software was fixed since then, but in
ontario and north east USA they obviously had not fixed that load
shedding software a couple years ago during a hot summer's day).
The aurora borealis did not induce destructive currents, but the systems
detected an anomaly in currents and shut the line down.
Now, imagine the line between the home and the barn. Imagine that with
time, the ground at the barn becomes corroded and contact is no longer
really good and your switch there is no longer properly grounded and
some fuse blows to protect the circuits.
| Quote: | directly into electronics. With only one AC electric wire grounded
means AC electric is not sufficiently earthed.
|
Well, if you ground all three of the 2 phase wires that come into north
american homes, the electric utility will either love you because you
your huge electric consumption/bills, or will hate you because you're
shorting their grid  |
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JF Mezei
*nix forums Guru
Joined: 21 Jul 2005
Posts: 2556
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| Posted: Tue Jul 18, 2006 7:18 pm Post subject:
Re: http://h71000.www7.hp.com/?
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"Main, Kerry" wrote:
| Quote: | That is the job of those being paid to manage stuff like this. Some
monitoring processes in place did not work as expected and from what I
have heard, steps are being taken to address this.
If HP or any other business had to rely on a Cust notifying them of an
IT failure, then that would be a very poor IT infrastructure.
|
RELY ? No. But there should be an easy way to notify a business of a
problem being seen by customers and not necessarily detected in-house.
In the end, having the lwoer downtime is more important than some
artificial pride of being able to detect problem on your own.
I have seen many examples where those "alarm systems" did not detect or
alert the people of a failure.
| Quote: | Mmm .. Kind of why we stress DT solutions - not just DT systems.
|
And very bad publicity for this type of service when your own DT people
coudn't detect the failure of a crucial node (switch) that fed a whole
web site. |
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Dave Froble
*nix forums Guru
Joined: 21 Jul 2005
Posts: 1172
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| Posted: Tue Jul 18, 2006 8:32 pm Post subject:
Re: http://h71000.www7.hp.com/?
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JF Mezei wrote:
| Quote: | w_tom wrote:
EMP is so trivial that even an NE-2 neon glow lamp (a bulb rated in
milliamps) will make such transients irrelevant. If a transient
overwhelmed protection already inside appliances, this it was not EMP.
It was a direct strike.
This is not as simple. In the 1980s, much of quebec was thrown into
darkness because of aurora borealis a few thousand km north of montreal.
Those induced currents into the power lines from james bay and
protective circuits automatically shut then down and Hydro Québec's
software was ill conceived to automatically start load shedding and as a
result crashed everything. (our software was fixed since then, but in
ontario and north east USA they obviously had not fixed that load
shedding software a couple years ago during a hot summer's day).
The aurora borealis did not induce destructive currents, but the systems
detected an anomaly in currents and shut the line down.
Now, imagine the line between the home and the barn. Imagine that with
time, the ground at the barn becomes corroded and contact is no longer
really good and your switch there is no longer properly grounded and
some fuse blows to protect the circuits.
directly into electronics. With only one AC electric wire grounded
means AC electric is not sufficiently earthed.
Well, if you ground all three of the 2 phase wires that come into north
american homes, the electric utility will either love you because you
your huge electric consumption/bills, or will hate you because you're
shorting their grid
|
It's my understanding, (note, I'm not an expert), that lightening
doesn't travel inside a wire, it rides on the outside.
If I'm correct, then a simple grounded collar on the wire should strip
the lightening off the wire, if the collar provides a better path to ground.
You don't physically ground all wires.
Dave, just a victim, not an expert.
--
David Froble Tel: 724-529-0450
Dave Froble Enterprises, Inc. E-Mail: davef@tsoft-inc.com
DFE Ultralights, Inc.
170 Grimplin Road
Vanderbilt, PA 15486 |
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Bud--
*nix forums beginner
Joined: 18 Jul 2006
Posts: 2
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| Posted: Tue Jul 18, 2006 8:53 pm Post subject:
Re: http://h71000.www7.hp.com/?
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w_tom wrote:
| Quote: |
Electronics already contain internal protection. Protection that can
be overwhelmed if a destructive surge is not earthed before entering
the building. My apathy for adjacent protectors is because anything at
the electronics that will protect those electronics is already inside
electronics. Experience has demonstrated how adjacent (and not
earthed) protectors even contributed to damage of adjacent (and powered
off) electronics.
|
I expect that is antipathy, not apathy.
The IEEE and the NIST both say plug-in point-of-use surge protectors are
effective.
The best paper I have seen on surge protection is at
http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf
- this a paper w_tom originally provided a link to
- the title is "How to protect your house and its contents from
lightning: IEEE guide for surge protection of equipment connected to AC
power and communication circuits"
- it was published by the IEEE in 2005
A second reference is
http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf
- this is the "NIST recommended practice guide: Surges Happen!: how to
protect the appliances in your home"
- it is published by the National Institute of Standards and Technology,
the US government agency formerly called the National Bureau of Standards
- it was published in 2001
Both guides were intended for wide distribution to the general public to
explain surges and how to protect against them. The IEEE guide was
targeted at people who have some (not much) technical background. Read
one (or both) to understand surges and protection.
Both say plug-in surge suppressors are effective.
Note that if a device, like a computer, has connections other than
power, like LAN, it has to be connected through the surge suppressor
also. This type of suppressor is called a surge reference equalizer
(SRE) by the IEEE (also described by the NIST). The idea is that all
wires connected to the device (power, phone, CATV, LAN, ...) are clamped
to the common ground at the SRE. The voltage on all wires passing
through the SRE to the protected device are held to a voltage safe to
the device.
| Quote: |
Dave Froble wrote:
I seem to remember your apathy for the battery backup and surge
protection units. :-)
Still, one does what one can. I have the units supplying power to most
electronics. I use the RJ45 ports in the units for network lines.
The problem is that I'm connecting 4 buildings via underground conduit.
Not very far underground. I think one is about 6 inches deep, another
maybe 12 inches.
Electrical entrances are all properly grounded. The phone lines have
the protection you mentioned. Unless there is a direct contact, I
should be protected. I'm thinking that the several hundred feet in each
conduit just might be picking up an EMP. I never would have thought
this would happen, but I can not find anywhere in the system that isn't
protected.
|
In addition to direct pickup in the network wires, the grounds at
different buildings can be at significantly different potentials. This
can be caused by earth current resulting from a lightning strike, or
other cause. That ground potential difference would appear at a computer
between the power and LAN connection. Incoming LAN wires should have a
protector block with short ground conductor run to electric service
grounding electrode conductor, like phone wires. And/or SRE at computer.
Using fiber optic would be another fix, or wireless.
bud-- |
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Main, Kerry
*nix forums Guru
Joined: 22 Jul 2005
Posts: 399
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| Posted: Tue Jul 18, 2006 9:20 pm Post subject:
RE: http://h71000.www7.hp.com/?
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| Quote: | -----Original Message-----
From: JF Mezei [mailto:jfmezei.spamnot@teksavvy.com]
Sent: July 18, 2006 3:18 PM
To: Info-VAX@Mvb.Saic.Com
Subject: Re: http://h71000.www7.hp.com/?
"Main, Kerry" wrote:
That is the job of those being paid to manage stuff like this. Some
monitoring processes in place did not work as expected and
from what I
have heard, steps are being taken to address this.
If HP or any other business had to rely on a Cust notifying
them of an
IT failure, then that would be a very poor IT infrastructure.
RELY ? No. But there should be an easy way to notify a business of a
problem being seen by customers and not necessarily detected in-house.
In the end, having the lwoer downtime is more important than some
artificial pride of being able to detect problem on your own.
I have seen many examples where those "alarm systems" did not
detect or
alert the people of a failure.
|
Well, there is also the contact Webmaster link on the main HP web site
under contacts.
| Quote: |
Mmm .. Kind of why we stress DT solutions - not just DT systems.
And very bad publicity for this type of service when your own
DT people
coudn't detect the failure of a crucial node (switch) that fed a whole
web site.
|
No excuses, but as I mentioned, there were management processes and
tools in place that failed to work as expected. As I understand it, this
is being addressed.
Regards
Kerry Main
Senior Consultant
HP Services Canada
Voice: 613-592-4660
Fax: 613-591-4477
kerryDOTmainAThpDOTcom
(remove the DOT's and AT)
OpenVMS - the secure, multi-site OS that just works. |
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John Santos
*nix forums Guru Wannabe
Joined: 25 May 2005
Posts: 189
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| Posted: Tue Jul 18, 2006 10:04 pm Post subject:
Re: http://h71000.www7.hp.com/?
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Dave Froble wrote:
| Quote: | JF Mezei wrote:
w_tom wrote:
EMP is so trivial that even an NE-2 neon glow lamp (a bulb rated in
milliamps) will make such transients irrelevant. If a transient
overwhelmed protection already inside appliances, this it was not EMP.
It was a direct strike.
This is not as simple. In the 1980s, much of quebec was thrown into
darkness because of aurora borealis a few thousand km north of montreal.
Those induced currents into the power lines from james bay and
protective circuits automatically shut then down and Hydro Québec's
software was ill conceived to automatically start load shedding and as a
result crashed everything. (our software was fixed since then, but in
ontario and north east USA they obviously had not fixed that load
shedding software a couple years ago during a hot summer's day).
The aurora borealis did not induce destructive currents, but the systems
detected an anomaly in currents and shut the line down.
Now, imagine the line between the home and the barn. Imagine that with
time, the ground at the barn becomes corroded and contact is no longer
really good and your switch there is no longer properly grounded and
some fuse blows to protect the circuits.
directly into electronics. With only one AC electric wire grounded
means AC electric is not sufficiently earthed.
Well, if you ground all three of the 2 phase wires that come into north
american homes, the electric utility will either love you because you
your huge electric consumption/bills, or will hate you because you're
shorting their grid :-)
It's my understanding, (note, I'm not an expert), that lightening
doesn't travel inside a wire, it rides on the outside.
|
Skin effect? That's still on the conductor, just at the surface
of the wire and not in its core.
| Quote: |
If I'm correct, then a simple grounded collar on the wire should strip
the lightening off the wire, if the collar provides a better path to
ground.
|
Doesn't the (presumably) grounded service panel locate right at
the entrance to the house do this? (I'm 99.99% sure code requires
the service panel be grounded.) All the wires run through knockouts
in the metal wall of the panel, which creates a grounded collar.
| Quote: | You don't physically ground all wires.
|
Or does each individual leg require a separate collar? Even
so, if it is that easy, you would think it would be required
anywhere there's been a lightning storm in the last 100 years.
(I.E. the entire planet except maybe parts of Anarctica!)
If you actually need to ground each conductor, the way to do
it would be through a low-pass filter with the cutoff well
below 60Hz connect to the ground, or a high-pass filter with
the cutoff just below 60Hz in series with the AC circuit, or
both. Lightning is basically DC, so I think it would
induce a large DC pulse. Electric power is AC, and would
see the low-pass filter as high-resistance. (High enough
impedance at 60 Hz and no appreciable power would be lost.)
AC would pass right through the high-pass filter but DC
would see it as an open circuit.
Whole house surge protectors seem to cost enough ($150-$200
at Home Depot) that they probably consist of filters and not
just a grounded collar.
It's been 31 years since I studied electronics, so IANAEE!
| Quote: | Dave, just a victim, not an expert.
|
--
John Santos
Evans Griffiths & Hart, Inc.
781-861-0670 ext 539 |
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Beach Runner
*nix forums addict
Joined: 04 Feb 2005
Posts: 80
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| Posted: Wed Jul 19, 2006 12:41 am Post subject:
Re: http://h71000.www7.hp.com/?
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Mark Daniel wrote:
| Quote: | For an environment touting it's availability it's always a bit
disconcerting/disappointing/discouraging when the primary portal doesn't
respond. Second time in almost as many weeks I've gone to check What's
New and received no response.
KLAATU$ ping h71000.www7.hp.com
PING openvms.compaq.com (161.114.65.60): 56 data bytes
----openvms.compaq.com PING Statistics----
4 packets transmitted, 0 packets received, 100% packet loss
%SYSTEM-F-TIMEOUT, device timeout
|
Couldn't ping it, but I could open it no problem.
| Quote: | Not just my particular system or part of the Net either. I've tried it
from four hosts across three continents. |
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w_tom
*nix forums beginner
Joined: 19 Mar 2005
Posts: 28
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| Posted: Wed Jul 19, 2006 1:37 am Post subject:
Re: http://h71000.www7.hp.com/?
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JF Mezei wrote:
| Quote: | This is not as simple. In the 1980s, much of quebec was thrown into
darkness because of aurora borealis a few thousand km north of montreal.
Those induced currents into the power lines from james bay and
protective circuits automatically shut then down and Hydro Québec's
software was ill conceived to automatically start load shedding and as a
result crashed everything. (our software was fixed since then, but in
ontario and north east USA they obviously had not fixed that load
shedding software a couple years ago during a hot summer's day). ...
|
You are literally mixing apples and oranges. Two completely different
effects are discusses as if they were same. They have different
frequency domains. One is on feet of wire; other on hundred miles of
wire. Using your reasoning, I can also suggest that static electric
discharge can also upset the grid - the classic butterfly in Argentian
creating a tornado in Oklahoma. What happened in Quebec on a grid is
irrelevant to lightning inside a building.
Protection already inside electronics makes that nearby strike
irrelevant. Thousands of volts induced on an isolated wire becomes
only trivial volts when those few milliamps are conducted by an NE-2
glow lamp. We install properly earthed protection to make direct
strike irrelevant. That means the induced transient is even moreso
irrelevant.
Meanwhile worry more about a different type of induced transient. If
the wire earthing a direct lightning strike is bundled with other wires
(inches apart), then those other wires have a transient induced on
them. Did you confuse that induced transient with fields that also
might create an aurora borealis?
Worry first about how or if each wire entering a building is properly
earthed either by hardwire or via a 'whole house' protector. Ignore
other irrelevant rumors. Concentrate on what really does shunt
transients to earth without damage.. |
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w_tom
*nix forums beginner
Joined: 19 Mar 2005
Posts: 28
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| Posted: Wed Jul 19, 2006 2:09 am Post subject:
Re: http://h71000.www7.hp.com/?
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Dave Froble wrote:
| Quote: | It's my understanding, (note, I'm not an expert), that lightening
doesn't travel inside a wire, it rides on the outside.
If I'm correct, then a simple grounded collar on the wire should strip
the lightening off the wire, if the collar provides a better path to ground.
You don't physically ground all wires.
|
To enhance a protection system, industry professionals
(www.polyphaser.com) sell bulkheads for wires to pass through; further
increase wire impedance; further encourage a transient to find earth
before entering a building. But still, that transient must be provided
a better path to earth. Otherwise that bulkhead would accomplish
little.
Yes, you physically ground every wire either with a direct connection
(hardwire), or via a protector. Appreciate what an effective protector
does:
http://www.telebyteusa.com/primer/ch6.htm
| Quote: | Conceptually, lightning protection devices are switches to
ground. Once a threatening surge is detected, a lightning
protection device grounds the incoming signal connection
point of the equipment being protected. Thus, redirecting
the threatening surge on a path-of-least resistance
(impedance) to ground where it is absorbed.
Any lightning protection device must be composed of two
"subsystems," a switch which is essentially some type of
switching circuitry and a good ground connection-to allow
dissipation of the surge energy.
|
Coax cable is literally connected direct to earth ground - needs no
protector. Telephone line cannot make a hardwire connection.
Therefore the telco installs a 'whole house' protector (for free) to
ground each wire of their cable to your earthing electrode. Earthing
as defined by telebyteusa.com. Earthing as in the most critical
component in every protection system as defined by an industry
benchmark, repeatedly, in application notes:
http://www.polyphaser.com/ppc_ptd_home.aspx
Those representing ineffective protectors (made obvious by no
dedicated earthing connection) hope you never learn what a responsible
protector manufacturers connects to - single point earth ground. Every
wire entering the building must either dump that transient into earth
before the wire enters a building - or that transient will find
destructive paths via interior electronics.
Electricity travels outside the wire and in the skin of the wire.
Irrelevant to what you need know. Protection means earthing a
transient long before that transient can overwhelm internal electronics
protection. A non-destructive transient is made so by a wired
connection to earth. Literally, transient electricity is dumped into
earth at the service entrance or finds earth via your electronics. A
principle demonstrated byBen Franklin in 1752. |
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JF Mezei
*nix forums Guru
Joined: 21 Jul 2005
Posts: 2556
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| Posted: Wed Jul 19, 2006 6:26 am Post subject:
Re: http://h71000.www7.hp.com/?
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w_tom wrote:
| Quote: | You are literally mixing apples and oranges. Two completely different
effects are discusses as if they were same.
|
The point I was making is that some protection scheme can be thrown off
by unforeseen events. And some may not actually protect from an event
that happens under just slightly different circumstances. |
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Bud--
*nix forums beginner
Joined: 18 Jul 2006
Posts: 2
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| Posted: Wed Jul 19, 2006 8:13 am Post subject:
Re: http://h71000.www7.hp.com/?
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John Santos wrote:
| Quote: | Dave Froble wrote:
JF Mezei wrote:
w_tom wrote:
EMP is so trivial that even an NE-2 neon glow lamp (a bulb rated in
milliamps) will make such transients irrelevant. If a transient
overwhelmed protection already inside appliances, this it was not EMP.
It was a direct strike.
|
Can also induce surge on non-protected ports like speaker lines causing
equipment failure.
| Quote: |
It's my understanding, (note, I'm not an expert), that lightening
doesn't travel inside a wire, it rides on the outside.
|
Can also be carried on the center conductor of coax.
| Quote: |
Skin effect? That's still on the conductor, just at the surface
of the wire and not in its core.
If I'm correct, then a simple grounded collar on the wire should strip
the lightening off the wire, if the collar provides a better path to
ground.
|
A 'collar' would not likely increase the wire inductance significantly
and the increased inductance wouldn't block a lightning induced surge. A
collar wouldn't provide a path to ground unless there was a conductor to
grounded collar arc.
| Quote: |
Doesn't the (presumably) grounded service panel locate right at
the entrance to the house do this? (I'm 99.99% sure code requires
the service panel be grounded.) All the wires run through knockouts
in the metal wall of the panel, which creates a grounded collar.
You don't physically ground all wires.
Or does each individual leg require a separate collar? Even
so, if it is that easy, you would think it would be required
anywhere there's been a lightning storm in the last 100 years.
(I.E. the entire planet except maybe parts of Anarctica!)
If you actually need to ground each conductor, the way to do
it would be through a low-pass filter with the cutoff well
below 60Hz connect to the ground, or a high-pass filter with
the cutoff just below 60Hz in series with the AC circuit, or
both. Lightning is basically DC, so I think it would
induce a large DC pulse. Electric power is AC, and would
see the low-pass filter as high-resistance. (High enough
impedance at 60 Hz and no appreciable power would be lost.)
AC would pass right through the high-pass filter but DC
would see it as an open circuit.
Whole house surge protectors seem to cost enough ($150-$200
at Home Depot) that they probably consist of filters and not
just a grounded collar.
|
Surge protectors generally use MOVs - metal oxide varistors. A MOV is
essentially an open circuit until the voltage goes past a knee in the
characteristic curve, then the current rises very rapidly with
increasing voltage. They clamp the voltage across the MOV. They are like
a bidirectional Zenier diode.
In a service panel surge protector MOVs are connected L1-L2, L1-N, L2-N.
The neutral is earthed. When a surge hits, the voltage to neutral-earth
is clamped which causes a very large current to earth (maybe 100,000
amps). Ground potential to 'absolute earth potential' can rise thousands
of volts, but phone, CATV and other signal wires are clamped to the
grounded neutral through phone NID and CATV entrance block and all the
wires ride up with the power conductors.
Plug-in surge suppressors clamp the voltage H-N, H-G, N-G (and signal
wires should go through the protector and be clamped to surge protector
ground). The voltage between wires is clamped to a value that is safe
for connected equipment.
High current and a clamp voltage mean a MOV will absorb and dissipate
energy. If the energy is over the MOV rating the device will fail. They
also progressively degrade when hit with large surges.
Lightning produced surges are short pulses, maybe 10 microseconds rise
time and 100 microseconds decay. They have major high frequency
components. A low pass filter can provide minor attenuation but MOVs
provide the real protection.
bud-- |
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Bill Gunshannon
*nix forums Guru
Joined: 21 Jul 2005
Posts: 1019
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| Posted: Wed Jul 19, 2006 11:31 am Post subject:
Re: http://h71000.www7.hp.com/?
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|
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In article <9d598$44bde880$4213eb81$25617@dialupusa.net>,
Bud-- <remove.BudNews@isp.com> writes:
| Quote: |
Can also induce surge on non-protected ports like speaker lines causing
equipment failure.
|
As long as we're speaking of induced currents, I have an anecdote I just
have to share.
Being a ham operator myself, I was helping another ham (Jim Shea, KB5FB,
RIP) pack up his gear over in Germany as he prepared for his return home.
We had everything disconnected and most of the gear packed but his dipole
was still up and the unterminated coax lay on the floor. Electrical
storms were predicted. All of a sudden, the entire room became charged
with static electricity. If you reached for anything there was an
uncomfortable feeling accompanied by a 6-10 inch spark. A minute or two
later we saw the flash of lightening outside and heard the boom of thunder.
We quickly threw the coax out the window and waited for the storm to pass
before trying to take down the antenna. It's amazing how much static
electricity you can collect with a 160 Meter Dipole 80-100 feet high.
bill
--
Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
bill@cs.scranton.edu | and a sheep voting on what's for dinner.
University of Scranton |
Scranton, Pennsylvania | #include <std.disclaimer.h> |
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