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Message Digest
Volume 28 : Issue 129 : "text" Format
Messages in this Issue:
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings)
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: CO backup power (was Re: FiOS in MDU Buildings
Re: Waveguide (was "size a major consideration...")
Re: Waveguide (was "size a major consideration...")
Re: Waveguide (was "size a major consideration...")
Re: Waveguide (was "size a major consideration...")
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Date: Sat, 09 May 2009 12:05:35 -0700
From: Sam Spade <sam@coldmail.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <3ukNl.73527$3k7.36552@newsfe17.iad>
Julian Thomas wrote:
> On Wed, 6 May 2009 10:37:51 EDT Wesrock@aol.com wrote:
>
>> The traditional Central Office had a diesel generator in addition to
>> its batteries, so a few days is not a problem.
>
> IIRC ESS1 (Morris Ill.) had minimal batteries, and a system that was supposed
> to start the diesels within 1/3 sec after a primary power failure.
>
> I have no idea as to how that worked out or was modified.
1/3 of a second to start the sequence perhaps. But, the generator
wouldn't be ready for awhile after that.
Didn't the batteries power the ESSes in Manhattan for about 4 hours
before it all died way back when?
------------------------------
Date: Sat, 9 May 2009 20:29:19 EDT
From: Wesrock@aol.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <c74.4ecffdbb.373779df@aol.com>
In a message dated 5/9/2009 8:54:13 AM Central Daylight Time, jt@jt-mj.net
writes:
> IIRC ESS1 (Morris Ill.) had minimal batteries, and a system that was
> supposed to start the diesels within 1/3 sec after a primary power
> failure.
Several seconds--maybe a minute or more--are required for sirens or
horns to notify persons near a generator that it is getting ready to
autostart. No way it could start in 1/3 sec.
Wes Leatherock
wesrock@aol.com
wleathus@yahoo.com
------------------------------
Date: Sat, 9 May 2009 15:15:23 -0500
From: "Who Me?" <hitchhiker@dont.panic>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <2slNl.6854$Lr6.3076@flpi143.ffdc.sbc.com>
Julian Thomas wrote:
> IIRC ESS1 (Morris Ill.) had minimal batteries, and a system that
> was supposed to start the diesels within 1/3 sec
> after a primary power failure.
I think your memory is failing you. All the #1 ESS offices in
Illinois that I visited/worked in ... which were a LOT, had battery
power for about 4 hours and were routinely tested on batteries for an
hour. Most had diesel generators that were manual start only.
That was pretty much state of the art when the original ESS machines
went in. I suspect that the recent vintage digital offices rely more
on generators and less on batteries but the total current drain is
MUCH less and I've only seen a few of them ... and didn't pay much
attention to the power plants.
Not really practical to start a diesel that quickly ... because it
(usually) needs to warm up a bit for the speed to stabilize before you
cut the load to it. Something like a backup system powered by natural
gas may not have that limitation but when you have any battery backup
at all, it isn't desirable to start the generator that quickly, to
prevent false starts on momentary "hits".
------------------------------
Date: Sun, 10 May 2009 08:54:52 -0600
From: Robert Neville <dont@bother.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings)
Message-ID: <kgqd05lbe8h18gbh19st3t31ankda4c22c@4ax.com>
Nikki Kelly"Who Me?" <hitchhiker@dont.panic> wrote:
> All the #1 ESS offices in Illinois that I visited/worked in
> ... which were a LOT, had battery power for about 4 hours and were
> routinely tested on batteries for an hour. Most had diesel
> generators that were manual start only.
I can recall touring an Illinois Bell ESS CO southwest of Chicago back
in the 70s. Memory fades over time, but I recall the basement filled
with the largest lead acid battery farm I'd ever seen. Wooden
floors/shelves everywhere.
I don't recall the expected life of that battery backup capacity, but
it seems to me it was on the order of days, not minutes.
------------------------------
Date: Sun, 10 May 2009 09:32:14 -0700
From: Sam Spade <sam@coldmail.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <ikDNl.13884$%_2.10757@newsfe04.iad>
Who Me? wrote:
> Julian Thomas wrote:
>
>> IIRC ESS1 (Morris Ill.) had minimal batteries, and a system that
>> was supposed to start the diesels within 1/3 sec
>> after a primary power failure.
>
>
> I think your memory is failing you. All the #1 ESS offices in
> Illinois that I visited/worked in ... which were a LOT, had battery
> power for about 4 hours and were routinely tested on batteries for an
> hour. Most had diesel generators that were manual start only.
If I recall correctly, too much testing could greatly shortened those
expensive battery's lives. They were (are) designed to "float" rather
than operating on a current-draining load.
------------------------------
Date: Sun, 10 May 2009 19:42:12 -0500
From: "Who Me?" <hitchhiker@dont.panic>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <asKNl.6899$Lr6.472@flpi143.ffdc.sbc.com>
Sam Spade wrote:
> If I recall correctly, too much testing could greatly shortened
> those expensive battery's lives. They were (are) designed to
> "float" rather than operating on a current-draining load.
Ahem. No battery is designed to float. They are designed to provide
power ... and float when not doing that. I worked in those offices for 25
years and I assure you that their capacity to provide that power WAS tested
regularly.
Except for a bomb or fire, there isn't really much that will damage a 2.1
volt CELL that stands 4 feet high and is about 16 inches square; they really
aren't fragile, mechanically OR electrically!
------------------------------
Date: Sun, 10 May 2009 12:16:50 -0500
From: Hudson Leighton <hudsonl@skypoint.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <hudsonl-ADB4C6.12165010052009@news.isp.giganews.com>
In article <2slNl.6854$Lr6.3076@flpi143.ffdc.sbc.com>,
"Who Me?" <hitchhiker@dont.panic> wrote:
>
> Not really practical to start a diesel that quickly ... because it
> (usually) needs to warm up a bit for the speed to stabilize before you
> cut the load to it. Something like a backup system powered by natural
> gas may not have that limitation but when you have any battery backup
> at all, it isn't desirable to start the generator that quickly, to
> prevent false starts on momentary "hits".
I have see some computer room backup diesels that start up that fast,
heated cooling system to keep the block at operating temperature, and
hydraulic starters that will spin fast enough that there is power
output even if the diesel doesn't start on the 1st rotation.
-Hudson
------------------------------
Date: Sun, 10 May 2009 23:05:53 +0000 (UTC)
From: David Lesher <wb8foz@panix.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <gu7mkh$a6u$1@reader1.panix.com>
"Who Me?" <hitchhiker@dont.panic> wrote:
>
> Not really practical to start a diesel that quickly ... because it
> (usually) needs to warm up a bit for the speed to stabilize before you
> cut the load to it.
The Diesels at a nuke plant are kept heated and have "start & provide
power" times in the low single-digit seconds; they are how you power an
emergency shutdown...
--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
------------------------------
Date: Sun, 10 May 2009 20:27:23 -0400 (EDT)
From: "Julian Thomas" <jt@jt-mj.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <100.407e0500eb70074a.005@jt-mj.net>
On Sat, 9 May 2009 15:15:23 -0500 Who Me? wrote:
>
>
>> IIRC ESS1 (Morris Ill.) had minimal batteries, and a system that
>> was supposed to start the diesels within 1/3 sec
>> after a primary power failure.
>
>I think your memory is failing you. All the #1 ESS offices in
>Illinois that I visited/worked in ... which were a LOT, had battery
>power for about 4 hours
Maybe, but my memory was from how it was 'supposed to work' a few years before
Morris went live.
--
Julian Thomas: jt@jt-mj.net http://jt-mj.net
In the beautiful Genesee Valley of Western New York State!
-- --
If God had intended man to smoke, He would have set him on fire.
------------------------------
Date: Sat, 9 May 2009 19:06:04 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: CO backup power (was Re: FiOS in MDU Buildings
Message-ID: <63b5c1ae-744c-4dfe-b187-2a6eade236c2@n4g2000vba.googlegroups.com>
On May 9, 9:53 am, "Julian Thomas" <j...@jt-mj.net> wrote:
> IIRC ESS1 (Morris Ill.) had minimal batteries, and a system that was
> supposed to start the diesels within 1/3 sec after a primary power
> failure.
That seems very doubtful. First, Morris, IL was not an "ESS1" but a
laboratory experiment. Second, since electronic switching must have
constant power or everything fails I would suspect the battery would
be much longer lasting
There was a post divesture case in NYC where a central office was, by
agreement, cut off from commercial power. But they forget to certain
tasks. The switch ran about four hours until the batteries ran out
but the staff was aware at a training class. Kind of a big scandal
for AT&T since it was a planned shutdown.
------------------------------
Date: Sat, 09 May 2009 20:42:03 GMT
From: "Tony Toews \[MVP\]" <ttoews@telusplanet.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Waveguide (was "size a major consideration...")
Message-ID: <kspb05pdvi50j9gqle4d5d50d6avmfd583@4ax.com>
David Lesher <wb8foz@panix.com> wrote:
> Noise - L carrier had to have a noise generator (yes, that's right)
> to _ADD_ noise to the calls, because subscribers were so used to the
> "long distance hiss" that they would hang up during lulls in a
> conversation, assuming that the call had been disconnected.
A friend switched [his company's] office phone system over to a VOIP
system, which runs on several dedicated ADSL connections to his office.
He mentioned that the VOIP system adds a small amount of hiss to the
signal just for the people on the phone.
BTW, he went to that system for a number of reasons compared to the
"oldish" Nortel system.
1) the phones were more expensive but used standard Ethernet (RJ45)
connectors. These phones can plug into any NATed system behind a
firewall and seamlessly work. As they are a construction company with
job sites scattered around western Canada all calls between job sites
and head office are now "free".
2) You can also use these phones at home if desired by plugging into
your home router/wireless access point/etc. My friend allocated
himself a phone at home just for after hours support calls and such.
3) It comes with software that integrates into Outlook, their corp
email and address book solution. He can select a contact and click on
a toolbar button. It rings his phone and once he picks up rings the
contacts phone.
4) Voicemail is sent to your email address as an MP3 file which you
can listen to if desired.
In the office [the phones are] run via Power Over Ethernet but [they]
use the standard wall warts/ power adapters elsewhere.
The VOIP provider is a phone company regulated by the CRTC here in
Canada. (Equivalent to the FCC with respect to telcos I think). They
have to have minumum capital and such. My friend then asked for the
appropriate documents proving they were regulated by the CRTC and
such. Which he got. But he was told he was the first person to
actually ask for the paperwork. Trust but verify is my motto.
Tony
--
Tony Toews, Microsoft Access MVP
Tony's Main MS Access pages - http://www.granite.ab.ca/accsmstr.htm
Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/
Granite Fleet Manager http://www.granitefleet.com/
------------------------------
Date: Sat, 09 May 2009 20:46:16 -0500
From: Neal McLain <nmclain@annsgarden.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Waveguide (was "size a major consideration...")
Message-ID: <4A0631E8.7050900@annsgarden.com>
Bill Horne wrote:
> What puzzles me is how microwave could be retired in favor of
> fiber, given the immense investment required to lay it: the
> cost of labor alone would dwarf all other considerations. How
> is fiber so much "better" than microwave?
> Did we just run out of radio channels?
Frequency congestion was certainly a factor, but I think path congestion
was a bigger factor. In order to avoid interference among microwave
paths, FCC rules require frequency coordination for any new microwave
path, or any new frequency use over an existing path. Under this
process, every license application must include a technical study
showing that the proposed antenna would not cause interference to, or
receive interference from, any existing terrestrial microwave antenna
using the same frequencies. As installed capacity grew, it became ever
more difficult to coordinate further capacity.
For common carriers using the 4-GHz band (3.7-4.2 GHz), this problem
became even more acute with the rise of C-band satellite antennas for
television signal distribution. Licensed C-band TVROs were usually
licensed for the entire 4-GHz band, effectively blocking construction of
any microwave link that would interfere with it.
Here is a link to my previous post about this subject:
http://tinyurl.com/6ot8ep
Bill continued:
> Capital Cost - I'm sure fiber is expensive to lay, but I
> suspect the rights of way are the big expense, and Microwave
> doesn't have that problem.
Right of way can indeed be expensive, but it depends on where you put
it. For construction in existing recorded easements and along state and
federal highways, ROW costs are usually limited to actual construction
costs plus pole rental if applicable.
Utility companies (including cable TV companies even though they're not
utilities under federal law) have the right to use any existing
"compatible" recorded easement, subject to any restrictions set forth in
the easement document. The definition of "compatible" has been the
subject of some litigation, but the law is on the side of the utility.
State governments usually don't impose rental charges for utility
facilities within state-owned ROW along state and federal highways.
(The same cannot be said for county and municipal ROWs, but that's a
subject for another day.)
The biggest drawback to construction on highways is the instability of
the property. Highway departments frequently do disruptive things like
widen traffic lanes, clean ditches, install culverts, install signs, and
plant landscaping. Adjacent landowners are forever mucking around
planting trees, building driveways, installing signs, and anything else
you can imagine.
For long intercity runs, the most stable ROWs are along railroads.
Unfortunately (for the utilities), railroad companies are keenly aware
of the value of their ROWs, and they charge accordingly. I've
encountered charges as high as $1.00 per foot per year for aerial
crossings. That might not sound like much, but it sure adds up fast!
(Factoid: many cable TV systems are designed as two separate networks
interconnected with ONE railroad crossing.)
As for common carriers like AT&T Long Lines, if they've already reached
capacity along existing microwave routes, building new microwave
capacity can be extremely expensive if not impossible. In urban areas,
it may not be possible to frequency-coordinate any new usable paths due
to potential interference to/from existing links and licensed TVROs.
And even if they build new capacity, it may not be enough for future
expansion. By contrast, as others have pointed out, fiber has
orders-of-magnitude greater capacity than microwave,
Bottom line: installing fiber may be the only option, even at railroad
companies' rental rates.
Neal McLain
------------------------------
Date: Sun, 10 May 2009 09:18:55 -0400
From: Curtis R Anderson <gleepy@gleepy.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Waveguide (was "size a major consideration...")
Message-ID: <4A06D43F.5030709@gleepy.net>
Scott Dorsey wrote:
> Scott Dorsey <kludge@panix.com> wrote:
>> Given the cost of Heliax, and the losses of generic coax at 70cm, is
>> it possible/advisable to homebrew waveguide? A previous post mentioned
>> circular waveguide, and I wonder if I could feed 70cm or 23cm antennas
>> with waveguide made from copper pipe.
>
> You could, but copper pipe is very expensive. It's cheaper to move the
> transceiver up closer to the antenna in most cases today.
>
> I'm not sure where the price breakeven point between hardline and waveguide
> is. You look at all those 2GHz Bell microwave towers with the cornucopia
> antennae, and you see waveguides coming down from all of them. These days
> that would all be done very differently.
Some good examples of the cornucopia horns with the attached
waveguides:
http://www.gleepy.net/gallery/images/p0001198.jpg
http://www.gleepy.net/gallery/images/p0001200.jpg
The pictures are from a Long Lines relay station just west of Warsaw,
NY taken in April 2001. The site is owned by American Tower these
days.
It was through this site that television network signals would have
passed from Los Angeles to Rochester, NY which I would have watched as
a child.
--
Curtis R. Anderson, Co-creator of "Gleepy the Hen", still
Email not munged, SpamAssassin [tm] in effect.
http://www.gleepy.net/ gleepy@intelligencia.com
gleepy@gleepy.net (and others) Yahoo!: gleepythehen
------------------------------
Date: Sun, 10 May 2009 14:35:08 -0700
From: AES <siegman@stanford.edu>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Waveguide (was "size a major consideration...")
Message-ID: <siegman-2F5AB6.14343810052009@news.stanford.edu>
In article <4A06D43F.5030709@gleepy.net>,
Curtis R Anderson <gleepy@gleepy.net> wrote:
> Some good examples of the cornucopia horns with the attached
> waveguides:
>
> http://www.gleepy.net/gallery/images/p0001198.jpg
> http://www.gleepy.net/gallery/images/p0001200.jpg
Nice pictures. I've previously heard these referred to as
"horn-reflector" or "sugarscoop" antennas.
They played a major role in the 1978 Nobel Prize in Physics.
<http://nobelprize.org/nobel_prizes/physics/laureates/1978/wilson-lecture
.pdf>
------------------------------
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