The Telecom Digest for November 16, 2010
Volume 29 : Issue 309 : "text" Format
Messages in this Issue:
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Date: Sun, 14 Nov 2010 19:10:57 -0600
From: "Michael G. Koerner" <mgk920@dataex.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: 274 NPA delayed for two years
Message-ID: <95ydncLHYr08FX3RnZ2dnUVZ_jCdnZ2d@ntd.net>
On 2010.11.13 09:14:51, Adam H. Kerman wrote:
> Michael G. Koerner<mgk920@dataex.com> wrote:
>
>> It's planned to overlay my home 920, delayed from 2012 to at least 2014.
>
>> http://www.postcrescent.com/article/20101112/APC03/311120177
>
> What number conservation measures does Wisconsin mandate?
I'm not really sure, but I would assume them to be the fairly standard ones,
such as carrier-to-carrier number portability, 1000 number block assignments, etc.
NXX assignments in 920 have been fairly slow over the past couple of years
anyways (conservation measures, wireless market saturation plus the blah
economy all to credit/blame?). Ditto in Wisconsin's 715, now 'officially'
overlaid by 534, but still without a 534 NXX in revenue service after about
four months of mandatory 10D local dialing and a significant number of
remaining 715 NXXs still unassigned.
--
___________________________________________ ____ _______________
Regards, | |\ ____
| | | | |\
Michael G. Koerner May they | | | | | | rise again!
Appleton, Wisconsin USA | | | | | |
___________________________________________ | | | | | | _______________
Date: Mon, 15 Nov 2010 09:29:38 -0500
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Once you hit send, you can forget privacy
Message-ID: <p06240849c906f3fb553e@[10.0.1.3]>
Once you hit send, privacy is gone
By Joseph P. Kahn
Globe Staff / November 15, 2010
The e-mail was clearly misguided in its interpretation of
intellectual-property rights and the Internet. It was also
dismissive, unapologetic, and, if made public, potentially far more
embarrassing to sender than recipient.
If? Try when.
A recent testy e-mail from Cooks Source managing editor Judith Griggs
to freelance writer and blogger Monica Gaudio read, in part, "you
should be happy we didn't just 'lift' your whole article and put
someone else's name on it!'' Gaudio posted the e-mail online, and it
went viral. When it did, one question about Griggs's judgment
eclipsed all others: How could anyone assume a communication like
that would remain private?
With minor variations, the same could be asked of others making news
recently with their private-made-public communications, ones that
quickly spread to social-media websites like Facebook and Twitter, to
gossip sites like Gawker and Deadspin, and to mainstream media sites
like Poynter Online - to the chagrin of those who composed them.
Tucker Carlson, who edits The Daily Caller, a political-journalism
website, posed as suspended MSNBC host Keith Olbermann in e-mails to
a Philadelphia columnist last week, then claimed he did not expect
that his prank e-mails would be published.
Campaign staffers for gubernatorial candidate Tim Cahill, the state
treasurer, e-mailed state Lottery officials last summer urging them
to launch a taxpayer-funded ad campaign likely to benefit him.
Harvard Law School student Stephanie Grace's e-mail to friends about
affirmative action and race touched off a furor on the Harvard campus
this year.
The NFL is investigating accusations that pro football star Brett
Favre sent explicit photos and messages to several women, most
notably a New York Jets sideline reporter who worked for the team
when he played there. Dozens of golfer Tiger Woods's text messages to
one of his mistresses, Joslyn James, were posted on her website in
March, tarnishing Woods's image and contributing to his divorce.
What part of "Forward With Attachments'' do these people not seem to
understand?
...
http://www.boston.com/ae/media/articles/2010/11/15/once_you_hit_send_you_can_forget_privacy/
Date: Mon, 15 Nov 2010 13:58:27 +1100
From: David Clayton <dcstar@myrealbox.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re:End to the mobile phone bores: New 'quiet' train carriages to block mobile phone signals
Message-ID: <pan.2010.11.15.02.58.25.4325@myrealbox.com>
On Sun, 14 Nov 2010 20:44:12 +0000, Stephen wrote:
> On Sun, 14 Nov 2010 09:54:11 +1100, David Clayton <dcstar@myrealbox.com>
> wrote:
>
>>http://www.dailymail.co.uk/sciencetech/article-1080866/End-mobile-phone-bores-New-quiet-train-carriages-block-mobile-phone-signals.html
>>
>>End to the mobile phone bores: New 'quiet' train carriages to block
>>mobile phone signals
>>
>>By Andrew Levy
>>Last updated at 3:03 AM on 28th October 2008
>
> seems a pretty old source?
Sorry, I saw it linked on a more recent article related to the general
subject. I thought it may be of interest if it hadn't already been posted
here.
>>
>>Mobile phones on the train could be a thing of the past as carriages are
>>to be layered with a film that blocks all transmissions
>>
> done on virgin trains in the UK (on all carriages).
>
> Now mainly removed due to complaints......
Do you know if it was it actually effective in totally blocking service or
just attenuating the signals enough just to make it unreliable?
--
Regards, David.
David Clayton
Melbourne, Victoria, Australia.
Knowledge is a measure of how many answers you have, intelligence is a
measure of how many questions you have.
Date: Mon, 15 Nov 2010 23:28:55 +0000
From: Stephen <stephen_hope@xyzworld.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re:End to the mobile phone bores: New 'quiet' train carriages to block mobile phone signals
Message-ID: <08g3e6t5lv4i95gl6ea30ge8hk89t08r40@4ax.com>
On Mon, 15 Nov 2010 13:58:27 +1100, David Clayton
<dcstar@myrealbox.com> wrote:
>On Sun, 14 Nov 2010 20:44:12 +0000, Stephen wrote:
>
>> On Sun, 14 Nov 2010 09:54:11 +1100, David Clayton <dcstar@myrealbox.com>
>> wrote:
>>
>>>http://www.dailymail.co.uk/sciencetech/article-1080866/End-mobile-phone-bores-New-quiet-train-carriages-block-mobile-phone-signals.html
>>>
>>>End to the mobile phone bores: New 'quiet' train carriages to block
>>>mobile phone signals
>>>
>>>By Andrew Levy
>>>Last updated at 3:03 AM on 28th October 2008
>>
>> seems a pretty old source?
>
>Sorry, I saw it linked on a more recent article related to the general
>subject. I thought it may be of interest if it hadn't already been posted
>here.
>>>
>>>Mobile phones on the train could be a thing of the past as carriages are
>>>to be layered with a film that blocks all transmissions
>>>
>> done on virgin trains in the UK (on all carriages).
>>
>> Now mainly removed due to complaints......
>
>Do you know if it was it actually effective in totally blocking service or
>just attenuating the signals enough just to make it unreliable?
it attenuates the signal a lot, but not enough to wipe out the signal
all the time.
it was most effective in the carriage - you could get a better signal
at the ends of the carriages (maybe the coach to coach connections are
not shielded?).
A Mobile would still just about work when you could have got 3 or 4
bars on a different train at the same spot.
the biggest impact is on 3G data which keeps "bouncing" in and out and
falling back to GPRS then cutting out completely.
Data was almost unuseable apart from close to a station or town centre
(didnt work as well actually in the stations - maybe all that metal
from the roofs?)
--
Regards
stephen_hope@xyzworld.com - replace xyz with ntl
Date: Mon, 15 Nov 2010 20:35:09 -0500
From: "Ala" <alackrity@comcast.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Users as Toast: The Blocking of Google TV
Message-ID: <FISdnR-bw7ZvQnzRnZ2dnUVZ_tadnZ2d@earthlink.com>
"Neal McLain" <nmclain@annsgarden.com> wrote in message
news:4CDF4869.8030501@annsgarden.com...
>
> Weinstein doesn't seem to understand any of this.
that would be a lot funnier if it were written during the bush days about
bush
Date: Mon, 15 Nov 2010 16:57:30 -0800
From: Thad Floryan <thad@thadlabs.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: More state-sponsored cyber attacks and mobile data breaches for 2011
Message-ID: <4CE1D6FA.403@thadlabs.com>
And the beat goes on ...
http://www.securityweek.com/researchers-predict-more-state-sponsored-cyber-attacks-and-mobile-data-breaches-2011
Researchers Predict More State-Sponsored Cyber Attacks and
Mobile Data Breaches in 2011
SecurityWeek News on Nov 15, 2010
A report released today by Imperva, a provider of data security
solutions, shares predictions on what we could expect to see in
2011 and is designed to inform and help IT security professionals
defend their organization against the next onslaught of cyber
security threats.
Imperva's research team predicts IT security professionals will
see the following in 2011:
* State-sponsored attacks, like the Stuxnet worm, will build on
concepts and techniques from the commercial hacker industry to
create more powerful Advanced Persistent Threats (APT).
* Greater transparency around insider security breaches and increased
incident reporting as a result of new regulations covering the act
of notification and disclosure.
* Increase in Man-in-the-Browser (MitB) Attacks will create growing
concern for online service providers who must be able to serve and
protect customers infected with some form of malware.
* Social network security measures will increase among prominent
social networks and tools, placing greater emphasis on security over
privacy as threat intelligence improves.
* Emphasis on file security in anticipation of data breaches where
compromised data is in the form of files rather than database
records.
* Compromised mobile devices resulting in data theft or loss as a
result of lagging security measures such as identification and
authentication and the spread of mobile malware.
* Cloud-based application and data security technologies will appear
as a late reaction to the move of many applications and data stores
to cloud technologies.
* Information security becomes a business process as CISOs and
security professionals seek to better protect data as it flows
through enterprise systems.
* Hacking industry will consolidate as amateurs are shut down and
mergers among larger, organized groups takes place.
* Convergence of data security and privacy regulation worldwide and
the emergence of a common framework as global businesses struggle to
meet multiple, complex mandates.
The report, compiled by Imperva's Application Defense Center (ADC) is
based on analysis of incident and vulnerability data from the past
year as well as findings from the company's Hacker Intelligence
Initiative and field work with enterprise customers.
"The threat landscape will evolve in many directions, making data
security more challenging than ever," said Imperva CTO Amichai
Schulman. "The biggest potential impact will be caused by the
proliferation of sophisticated mobile devices interacting with
corporate networks. I believe that next year will bring the first
major data breaches as a result of compromised devices. Additionally,
the evolution of Advanced Persistent Threat techniques will become an
even greater threat to organizations as states leverage these tools
for their own political and financial gain."
In a report released last week by WebSense, researchers are saying
that the latest tactics have moved to a political -- and nationalistic
stage, and that 2011 will bring blended threats and data loss over the
Web that demonstrate the potential for targeted cyberterrorism
attacks.
A full copy of the Imperva report is available here (registration required):
<https://www.imperva.com/lg/lgw.asp?pid=425>
Date: Sun, 14 Nov 2010 20:45:25 EST
From: Wes Leatherock <wesrock@aol.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re:End to the mobile phone bores: New 'quiet' train ...
Message-ID: <7f5e0.3da06cbb.3a11eab5@aol.com>
In a message dated 11/14/2010 5:59:06 PM Central Standard Time,
stephen_hope@xyzworld.com writes:
>On Sun, 14 Nov 2010 09:54:11 +1100, David Clayton
><dcstar@myrealbox.com> wrote:
>
>>http://www.dailymail.co.uk/sciencetech/article-1080866/End-mobile-phone-bores-New-quiet-train-carriages-block-mobile-phone-signals.html
>
>> End to the mobile phone bores: New 'quiet' train carriages to block
>> mobile phone signals
>
>> By Andrew Levy
>> Last updated at 3:03 AM on 28th October 2008
>
>seems a pretty old source?
>
>> Mobile phones on the train could be a thing of the past as carriages
>> are to be layered with a film that blocks all transmissions
>
>done on virgin trains in the UK (on all carriages).
>
>Now mainly removed due to complaints......
Did anybody note that the news item was from _www.dailymail.co.uk_
(http://www.dailymail.co.uk) . Thr Daily Mail, as you would expect,
is a British newspaper Also indicated by the URL ending in co.uk.
It's hard to evaluate any news report without knowing where it
originated.
Wes Leatherock
wesrock@aol.com
wleathus@yahoo.com
Date: Sun, 14 Nov 2010 21:20:10 -0600
From: Neal McLain <nmclain@annsgarden.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Users as Toast: The Blocking of Google TV [telecom
Message-ID: <4CE0A6EA.1040109@annsgarden.com>
Garrett A. Wollman wrote:
>> Weinstein doesn't seem to understand any of this. In fact, it appears
>> that he doesn't even understand the difference between broadcast
>> television program and non-broadcast television programming.
>
> No, I think Weinstein believes these distinctions are irrelevant
> relics of a bygone age. Obviously, the video programming aggregators
> disagree, hence the dispute.
Well, they are relics of a bygone age. Weinstein may be aware of
them, but if he is, he doesn't mention them.
> Why anyone would think it reasonable for Hulu to allow me to watch a
> Fox comedy on my laptop but not on my Google TV (if I had one, which I
> don't) is not clear to me, but monopolies do all sorts of unreasonable
> things to maximize the amount of wealth they extract from their
> customers, and Fox certainly has a monopoly on this particular
> entertainment product. The usual rules against tying only apply to
> market-created monopolies, not government-created ones like copyright.
But it's not copyright law that created broadcast monopolies; it's
communications law -- specifically, the grotesquely-misnamed "Cable
Television Consumer Protection and Competition Act of 1992." This act
created the whole structure, including defined geographic markets
(Nielsen DMA), the must-carry rules, and the retransmission-consent rules.
Your elected representatives in Congress call it "consumer protection."
Neal McLain
Date: Sun, 14 Nov 2010 23:24:42 -0600
From: Neal McLain <nmclain@annsgarden.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: History--computer based information operator terminal system
Message-ID: <4CE0C41A.30406@annsgarden.com>
Wes Leatherock wrote:
> In a message dated 11/13/2010 11:15:54 PM Central
> Standard Time, hanco...@bbs.cpcn.com writes:
>> I believe the original reason for ANC was because the
>> spelling of certain local exchange names wasn't the
>> same as it sounded. For example, most people upon
>> hearing "BAring" would think it's BEaring, not BA, or
>> LOmbard was LUmbard, not LO*. When calls were placed
>> by the operator who plugged into jack it didn't matter,
>> but when people were dialing it did matter.
> Bala-Cynwood was often cited as a prime example.
It's spelled Bala Cynwyd. Before they moved downtown, Comcast's
corporate office was in the GSB Building at One Belmont Avenue, Bala
Cynwyd PA 19004.
> Also note 1 and 0 could not be used in 2L-5N office codes
> because there were no letters associated with them on
> the dial. This made unusable a large number of office
> codes.
>
> ***** Moderator's Note *****
>
> Wes, I think it's the other way around: letters weren't
> assigned to "1" or "0" because those numbers were
> reserved for use in Area Codes (second digit) and
> Terminating Toll Center codes (First digit), and so
> they were never considered for use in the "AA" part of
> "AAN" Exchange codes.
Well, I think the reason is more fundamental than either of those
theories. Initial "1" wasn't used because of the possibility of dialing
a false "1" when removing the receiver from the switchhook, and initial
"0" was reserved for Operator. There were "no letters associated with
them on the dial" precisely because they couldn't be used as initial
digits.
These restrictions existed as early as 1933, long before area codes were
introduced. It was indeed a happy coincidence that "1" and "0" were
available when area codes were introduced, but I don't think area codes
were even contemplated back in '33.
Here's what Miller had to say in 1933:
| The limitation of eight offices exists because the
| number 0 /as a preliminary digit/ is reserved for
| reaching the operator, and the digit 1 cannot be
| distinguished from an accidental preliminary depression
| of the switchhook. Since neither of these can be used to
| designate central offices, the eight digits two to nine,
| inclusive, remain for this purpose.
Slashes indicate italics in the original.
Source: Kempster B. Miller, M.E. Telephone Theory and Practice:
Automatic Switching and Auxiliary Equipment. First Edition. New York:
McGraw Hill, 1933, 20.
Neal McLain
Date: Mon, 15 Nov 2010 00:57:33 -0600
From: Neal McLain <nmclain@annsgarden.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Why is T-1 24 Channels?
Message-ID: <4CE0D9DD.8020101@annsgarden.com>
Fred Goldstein wrote:
> Bill Horne wrote:
>
>> Yes, we've seen this before, but I couldn't resist the
>> chance to play "Ultimate Telecom Trivia"! Here's the
>> question: why does a T1 line have 24 channels?
>
> Bill, Neal's answer sounds right to me too, modulo slight
> editing.
Thanks Fred!
> Neal McLain <nmcl...@annsgarden.com> wrote,
>> Because:
>> - The circuit uses Pulse Code Modulation with a
>> sampling rate of 128 steps, so 7 bits (plus one
>> check bit) must be transmitted for each sample.
> Indeed; the D1 channel bank was 7-bit PCM, vs.
> 8 bit later; the "robbed" bit is for signaling,
> not parity.
I stand corrected. Thanks for the correction.
>> - Manholes in urban areas are about 6000 feet apart,
>> which is the distance between loading coils in a voice
>> loop.
>>
>> - Data repeaters have to be accessible for service
>> (i.e., in manholes), so they must be 6000 feet apart.
> Manholes are much closer together than that, as needed
> for pulling and access.
I didn't mean to imply that manholes at 6000-foot spacing were the only
manholes.
I'm certainly familiar with the need for pulling and access. Back in my
CATV days, we occasionally used buried conduits (either our own or
rented from telco) in urban locations. Telcos wouldn't let us share
conduits with their own facilities, but they often had spare conduits
for lease. Wisconsin Telephone charged us $0.68 per conduit foot per
year, plus an extra ten feet for every manhole. If we needed access at
a point where telco didn't have a manhole, we'd typically install a
handhole or pedestal.
WisTel even let us connect our own conduits to their manholes. I recall
one memorable project in downtown Madison, about a block from the State
Capitol, where we installed our own conduits but passed through one of
their manholes. The charge for that ten feet: $6.80 per year. Compared
to the cost of building our own manhole, that's by far the best deal we
ever got from Wisconsin Tel!
Neal McLain
Date: Mon, 15 Nov 2010 23:06:45 -0500
From: Bill Horne <bill@horneQRM.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Why is T-1 24 Channels?
Message-ID: <20101116040645.GA8763@telecom.csail.mit.edu>
On Mon, Nov 15, 2010 at 12:57:33AM -0600, Neal McLain wrote:
> Fred Goldstein wrote:
> > Neal McLain <nmcl...@annsgarden.com> wrote,
>
> >> Because:
>
> >> - The circuit uses Pulse Code Modulation with a
> >> sampling rate of 128 steps, so 7 bits (plus one
> >> check bit) must be transmitted for each sample.
>
> > Indeed; the D1 channel bank was 7-bit PCM, vs.
> > 8 bit later; the "robbed" bit is for signaling,
> > not parity.
>
> I stand corrected. Thanks for the correction.
The D-1 bank used 8-bit samples: the low-order bit was robbed for
signalling only when on-hook, i.e., when the circuit was in use, the
8th bit was part of the PCM sample. Some call this "Seven and One-Half
Bit" sampling.
This caused, of course, an ambiguity in supervision, since the
low-order bit had to be timed by the banks to check that it was in the
on-hook state for several frames before the bank would assert on-hook
for the channel.
BTW, I believe that robbed-bit signalling was the reason for ISDN's
poor reputation during it's breif heyday as a data communications
tool: even after Extended SuperFrame (ESF) removed signalling info
from the individual channels' PCM stream, the Baby Bells were
reluctant to retire their gargantuan inventory of seven-and-one-half
bit circuit packs, so ISDN users were usually limited to 56 Kbps
connections during data calls (bonding excepted, of course). There had
been some limited progress toward "End-to-end-eight-bit" trunk groups
toward the middle-to-late Nineties, but since ISDN calls were billed
per-minute, most consumers preferred to use modems and "local" access
numbers, which resulted in developments that pushed speeds to the
56Kbps range on dialup modems, thus pounding the last nail into ISDN's
coffin.
Had the trunk network been 8-bit capable at the start of the PC
revolution, ISDN might have gotten enough traction to survive.
Bill Horne
--
(Filter QRM for direct replies)
Date: 16 Nov 2010 04:37:33 -0000
From: John Levine <johnl@iecc.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: ISDN, was Why is T-1 24 Channels?
Message-ID: <20101116043733.70834.qmail@joyce.lan>
>BTW, I believe that robbed-bit signalling was the reason for ISDN's
>poor reputation during it's breif heyday as a data communications
>tool: even after Extended SuperFrame (ESF) removed signalling info
>from the individual channels' PCM stream, the Baby Bells were
>reluctant to retire their gargantuan inventory of seven-and-one-half
>bit circuit packs, so ISDN users were usually limited to 56 Kbps
>connections during data calls (bonding excepted, of course).
Not quite. Data calls were 8-bit, but the Bells, in their eternal
quest to maximize short term revenue and drive customers away, charged
more for data calls than for voice calls. Typically voice calls were
unmetered, but data cost several cents per minute. Users, not being
totally stupid, noticed that so long as they only used the high seven
bits, they could send data using voice calls. Fred remembers more
details than I do, but my recollection is that this was known as
DOVBS, data over voice bearer service.
The main reason that ISDN died is that the telcos grossly overpriced
it, but it also didn't help that the North American version was and is
painful to configure, with the equipment at both ends having to be
manually programmed, and it didn't work if the programming didn't
precisely match. I dunno why they did that, Euro-ISDN was plug and
play and is still reasonably popular. In the US ISDN is dead other
than for PRI trunks to PBXes, carried over T-1, natch.
R's,
John
***** Moderator's Note *****
I don't often disagree with John, but this time I will. ISDN (at least
the kind offered by New England Telephone) could provide both 56Kbps and
64Kbps data connections, with 64Kbps requests optionally downgraded
to 56Kbps if no "Eight bit clean" path was available from the
originating to the terminating CO.
DOVBS was sometimes used to place a "voice" call that was actually
carrying data, but it was not the only way to use a 56Kbps bearer
channel: ISDN lines would accept legitimate requests for either 56Kbps
or 64Kbps data bearer connections. I'm sure of this, because my ISDN
"modem" offered the option to either refuse a non-64Kbps connection if
64Kbps had been requested, or to accept a 56Kbps connection
instead. Since dialing a call didn't cost anything, I had the ISDN
interface programmed to "war dial" my ISP until it got a 64Kbps
connection: N.E.T. charged the same rate for both speeds.
Bill Horne
Moderator
Date: Mon, 15 Nov 2010 19:50:47 -0800 (PST)
From: Lisa or Jeff <hancock4@bbs.cpcn.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: End to the mobile phone bores: New 'quiet' train carriages to block
Message-ID: <53ca20b5-ad1e-4188-b385-37def9dadcfb@p11g2000vbn.googlegroups.com>
On Nov 13, 5:54 pm, David Clayton <dcs...@myrealbox.com> wrote:
> Mobile phones on the train could be a thing of the past as carriages are
> to be layered with a film that blocks all transmissions
This is not a good idea.
Railroad passenger trains are increasingly automated so there are
fewer crewman on board, sometimes only the motorman. In the event of
any kind of situation or emergency, passengers having cellphones can
expedite calling for help. (I once needed to report a disruptive
passenger because there was no conductor around.)
> Some train companies have introduced 'quiet' carriages in an attempt to
> give passengers a break from the racket.
Actually, these have been very successful where they've been tried.
We need more of them. (I wish they'd have them on weekend trains,
which are especially noisy.)
Date: Mon, 15 Nov 2010 20:08:17 -0800 (PST)
From: Lisa or Jeff <hancock4@bbs.cpcn.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: TELEPHONE SWITCHBOARD IN HAVRE DE GRACE MD
Message-ID: <c6b6152f-4885-4dc5-b6c4-60ddc08a59ca@j33g2000vbb.googlegroups.com>
On Nov 12, 9:39 am, "Quinn, Michael J." <mqu...@mitre.org> wrote:
> I came across a small telephone patch-panel corded switchboard in Havre de
> Grace MD last weekend at an antique shop. Appeared to be in reasonably good
> shape to my untrained eye, and carried a 215 area code on the dial unit, so
> presumably came from a small business or hotel in the Philadelphia area
> about 75 miles north. I'm not enough of a telephone aficionado for the $950
> price tag to fit my budget, but I thought I'd pass the info along to the TD
> forum
I tried various ways to get to a website for that shop but could not.
I don't feel like telephoning the place since I'm not seriously
interested in purchasing the board.
But I am curious about it, such as what kind of model it is, and
whether it's for a manual or dial PBX. Manual boards have a light and
jack for each extension, but dial PBXs have only the jack. Dial PBXs
have an attendant field and an intercept field. Some PBXs had
conference jacks and tie-line fields.
In the late 1950s Bell introduced the 608 PBX which was more modern
looking and had a light backboard instead of black and push buttons.
But a great many of the older black units remained in service.
I knew a collector who had a 555 and installed it in his house. Home
lines aren't intended for PBXs but his home line still worked on it.
One study said cord switchboards did not wear out, that is, they were
replaced by automation before they became so old or worn they didn't
work well or couldn't be easily repaired. Of course, today it likely
would cost far more to build a manual cord board with its internal
banks of relays than a modern computerized PBX.
I wonder if any cord PBXs are still in real (not 'for display or
nostalgia') service in North America. The efficiencies by modern
systems and lack of replacement parts probably made them all
economically obsolete.
As an aside, in the 1970s Bell introduced a manual cordless console
PBX to replace the 555. That meant an attendant still had to service
all calls which was economically expensive. I wonder how many units
they made. By the 1970s most businesses wanted dial service for
faster use and to save on the attendant salaries. Bell did come up
with newer cost-effective dial systems for even small sized offices.
Further, key systems grew more sophisticated, too.
I once saw a surplus cord manual switchboard that was for intercom use
only. That is, it had only extensions on it, no trunk circuits. It
was a Kellogg and it more or less worked.
Date: Mon, 15 Nov 2010 20:17:14 -0800
From: Richard <rng@richbonnie.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: early CATV, was: Bell System Technical Journal, 1922-1983
Message-ID: <k1m3e6p72ufci0v2rd9abvmphelkue5s4f@4ax.com>
On Sat, 13 Nov 2010 20:37:28 -0800 (PST), Lisa or Jeff
<hancock4@bbs.cpcn.com> wrote:
>--There's a website out there that talks about the old Bell System
>microwave network, much of it now apparently dismantled.
Most of it indeed is gone, at least in the sense of out of service.
Many of the towers still exist. There are a couple of them near my
home in southern Nevada.* The horn-reflector antennas are still on
top of most of the towers. The vertical circular waveguide is there.
Most of the horizontal rectangular waveguide runs are missing. The
buildings are intact. I cannot tell if there is any equipment inside.
However, the Bell System sometimes left radio and multiplex equipment
in place if it cost more to remove it than it was worth as salvage.
Around 1970, I was in a Long Lines main staion. I walked through an
aisle with unpowered equipment mounted in bays. On each bay was a
sign "R. I. P." meaning "Retired In Place." They would not remove the
equipment unless they needed the space for something new.
Most of the AT&T microwave towers, buildings and sites are owned by
American Tower, who is trying to lease space on them for other radio
uses such as cellphone.
Example site (nearest my home):
http://www.americantower.com/OASISPublic/SitePublicPage/SiteBrochure.asp?lngSiteID=1814&lngTowerid=-1
The photos of this tower show that the antennas and vertical waveguide
are still there. Most likely it would cost more to remove them than
their salvage value.
* I found the two towers while roaming the countryside looking for
sites for ham-radio repeaters. When I did find them, a wave of
nostalgia washed over me, because my job at Bell Labs involved
designing not only some of the radio equipment, but also improvements
in the antenna sidelobes and transmission irregularities in the
over-moded circular waveguide.
Dick
Date: Mon, 15 Nov 2010 21:15:32 -0800
From: Richard <rng@richbonnie.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: early CATV, was: Bell System Technical Journal
Message-ID: <jk24e6hs50n0u8r04ev5qfgarpa2rdp7dh@4ax.com>
On Sun, 14 Nov 2010 07:22:13 -0600, Neal McLain
<nmclain@annsgarden.com> wrote:
>Lisa or Jeff (hancock4@bbs.cpcn.com) wrote:
>
> > Additional TV trivia:
>
> > --A former governor of Pennsylvania in the 1970s,
> > Milton J. Shapp, made his fortune as a maker of
> > cable TV components.
>
>Milton JERROLD Shapp, founder of Jerrold Electronics
>http://theoldcatvequipmentmuseum.org/350/index.html#Shapp
>
> > --There's a website out there that talks about the old
> > Bell System microwave network, much of it now apparently
> > dismantled.
>
>http://long-lines.net/
>
> > Several towers were dedicated to just
> > television transmission. Indeed, does anyone know if
> > AT&T or the other LD carriers still supply transmission
> > facilities for broadcast television and radio networks?
> > Or is it all done by satellite today?
>
>I don't think towers were dedicated exclusively to television. AFAIK,
>AT&T used dedicated links in the same 4- and 6-GHz bands, and over the
>same geographic routes, that it used for voice circuits. Richard of
>Pahrump is our resident expert on such matters, so I'm sure he'll jump
>in here.
In the book "Transmission Systems For Communications", Bell Telephone
Laboratories, Inc., Fifth Edition, 1982, Page 481, talking about
microwave systems:
>Historically, the choice of baseband width has often been influenced
>by the requirements of television transmission. For example, in the
>TD-2 and certain short-haul systems, one of the baseband signals is
>a standard television signal requiring a 4.5-MHz baseband width.
>Likewise in the TH-l system, a l0-MHz baseband width was chosen
>in anticipation of l0-MHz high-definition television signals.
The AT&T microwave systems were designed for, and did carry, both
television and frequency-diplexed telephone. When not carrying TV
they fit as many voice channels on them as possible. At 4 GHz and
11 GHZ, channel spacing was 20 MHz, and each channel could carry one
NSTC video signal (audio was carried separately), or 1200 voice
circuits. At 6 GHz, channel spacing was 29.7 MHz, with a 10-MHz
baseband. It was intended to carry a higher-definition TV signal to
be used in theaters, however these systems never materialized. It
could carry 1860 voice circuits.
In my new-employee orientation classes, we were told that right after
World War II the Bell system designed the early microwave systems to
capture the emerging market for intercity TV transmission. Indeed,
the leading "T" in the system names (TD-2, TH-1, etc.) stood for
Television.
Dick
Date: Mon, 15 Nov 2010 20:22:47 -0800
From: Richard <rng@richbonnie.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: History--computer based information operator terminal system
Message-ID: <di14e6tibi74get3irnh5e8b4lk3pbvikl@4ax.com>
>***** Moderator's Note *****
>
>Wes, I think it's the other way around: letters weren't assigned to
>"1" or "0" because those numbers were reserved for use in Area Codes
>(second digit) and Terminating Toll Center codes (First digit), and so
>they were never considered for use in the "AA" part of "AAN" Exchange
>codes.
The old rule was: Area codes had a 1 or 0 as the second digit, and
office codes did not. This was particularly important in places like
New Jersey in 1970, where you did not have to dial 1 before a long
distance call. The switch looked at the second digit to see how many
digits to expect.
Dick
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