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The Telecom Digest for March 12, 2012
Volume 31 : Issue 67 : "text" Format
====== 30 years of TELECOM Digest -- Founded August 21, 1981 ======
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Telecom and VOIP (Voice over Internet Protocol) Digest for the
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Date: Sun, 11 Mar 2012 12:28:26 -0400
From: Bill Horne <bill@horneQRM.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Did anyone ever figure out where "E&M" came from?
Message-ID: <20120311162826.GA25121@telecom.csail.mit.edu>
I was at a lunch for ham radio operators yesterday, and the sea of
grey hair that I saw has put me in a reflective mood.
I've been searching through various archives this morning, without
success, trying to find out if anyone ever figured out the origin of
the "E & M" signalling lead designations. When I took the D-18 course
at New England Telephone, I read that the designations might have come
from old circuit diagrams for telegraph equipment, but that nobody
knew for sure.
Bill
--
Bill Horne
(Remove QRM from my address to write to me directly)
Date: Sun, 11 Mar 2012 14:07:59 -0400
From: "Gary" <bogus-email@hotmail.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Did anyone ever figure out where "E&M" came from?
Message-ID: <jjipm8$8eo$1@dont-email.me>
"Bill Horne" wrote in message
news:20120311162826.GA25121@telecom.csail.mit.edu...
>
> I've been searching through various archives this morning, without
> success, trying to find out if anyone ever figured out the origin of
> the "E & M" signalling lead designations.
I don't remember where I learned it, but I recall it means "Ear and Mouth."
-Gary
***** Moderator's Note *****
OK, I guess I didn't write very clearly. I know what the E&M leads do, and
the "Ear and Mouth" or "R/e/ceive and Trans/m/it" ways of telling them apart.
What I want to know is where the "E" designation came from; i.e.,
who/when someone decided to call the "receive" lead the "E" lead, and
likewise for the "M" lead. I was taught that these terms might have
come from "historical" documents, but that no one knew for sure.
So, let me put the question another way. Why is the receive lead
called "E" instead of "Z", or "Y", etc. Why is the transmit lead
called the "M" lead, instead of "X" or "W", etc.? Where were these two
letters first used in this context?
My thanks to the many respondents who sent in their posts.
Bill Horne
Moderator
Date: Sun, 11 Mar 2012 23:30:49 -0500
From: bonomi@host122.r-bonomi.com (Robert Bonomi)
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Did anyone ever figure out where "E&M" came from?
Message-ID: <VcCdnVRoGq1k5sDSnZ2dnUVZ_v2dnZ2d@posted.nuvoxcommunications>
In article <jjipm8$8eo$1@dont-email.me>, Gary <bogus-email@hotmail.com> wrote:
>"Bill Horne" wrote in message
>news:20120311162826.GA25121@telecom.csail.mit.edu...
>>
>> I've been searching through various archives this morning, without
>> success, trying to find out if anyone ever figured out the origin of
>> the "E & M" signalling lead designations.
>
>I don't remember where I learned it, but I recall it means "Ear and Mouth."
>
>-Gary
>
>***** Moderator's Note *****
>
>OK, I guess I didn't write very clearly. I know what the E&M leads do, and
>the "Ear and Mouth" or "R/e/ceive and Trans/m/it" ways of telling them apart.
>
>What I want to know is where the "E" designation came from; i.e.,
>who/when someone decided to call the "receive" lead the "E" lead, and
>likewise for the "M" lead. I was taught that these terms might have
>come from "historical" documents, but that no one knew for sure.
>
>So, let me put the question another way. Why is the receive lead
>called "E" instead of "Z", or "Y", etc. Why is the transmit lead
>called the "M" lead, instead of "X" or "W", etc.? Where were these two
>letters first used in this context?
>
>My thanks to the many respondents who sent in their posts.
I strongly suspect it was from very early telephones. Which had one
lead connected to the 'earpiece', and the other lead connected to the
'mouthpiece'. One side of the local battery was grounded, other side
ran to the microphone in the mouthpiece. 2nd side of the microphone went
out to the one of the phone wires. other phone wire came in and went to
one side of the speaker in the earpiece. 2nd side of the speaker went
to ground.
With the 'mouthpiece' and 'earpiece' being -separate- physical objects,
unlike the modern 'handset' -- which contains both elements -- and with
effectively -no- other components, naming the leads for the object to
which they connected ("earpiece"/"mouthpiece"") would seem 'intuitively'
obvious'.
***** Moderator's Note *****
I'm going to reserve judgement. The "E" and "M" leads have always been
for signalling AFAIK, and I suspect that the lead designations came
from some early duplex equipment drawings in the telegraph world.
Bill Horne
Moderator
Date: Sun, 11 Mar 2012 11:46:45 -0400
From: Bill Horne <bill@horneQRM.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: 'Offshoring Bill Becomes Big Focus of Rep. Hanna Town Hall
Message-ID: <jjihd6$k2o$1@dont-email.me>
This is from February, and I know that might be ancient history in the
"Instant Gratification" world of yesterday's news cycle, but I'm
interested to hear what others think about it, for two reasons:
1. I wonder if the CWA's action signals a return to union activism in
general, and, if so, what other confrontations the union has done.
2. I also wonder why the I haven't seen anything about it in the
national media.
Bill
'Offshoring Bill Becomes Big Focus of Rep. Hanna Town Hall
About 45 members of CWA Local 1126 just about took over the Utica,
N.Y., town hall meeting of Rep. Richard Hanna (R-N.Y.)
The activists, members of CWA's Legislative-Political Action Team,
pressed Hanna on his refusal so far to support the offshoring bill,
which would stop federal grants and loan guarantees to companies
that move call center jobs overseas.
Rest is at
http://www.cwa-union.org/news/entry/offshoring_bill_becomes_big_focus_of_rep._hanna_town_hall
-or-
http://tinyurl.com/6v3maes
P.S. There's a third thing that puzzles me, albeit not telecom related:
I wasn't able to copy the headline off the web page, at least with
Internet Exploder, and I had to call up the "Source" page to get a
version I could copy and paste into this post. Why?
--
Bill Horne
(Remove QRM from my address to write to me directly)
Date: Sun, 11 Mar 2012 22:48:14 -0500
From: bonomi@host122.r-bonomi.com (Robert Bonomi)
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: 'Offshoring Bill Becomes Big Focus of Rep. Hanna Town Hall
Message-ID: <y_Sdnf_tTr9j7MDSnZ2dnUVZ_rSdnZ2d@posted.nuvoxcommunications>
In article <jjihd6$k2o$1@dont-email.me>, Bill Horne <bill@horneQRM.net> wrote:
>
>P.S. There's a third thing that puzzles me, albeit not telecom related:
>I wasn't able to copy the headline off the web page, at least with
>Internet Exploder, and I had to call up the "Source" page to get a
>version I could copy and paste into this post. Why?
A) because you're using a borked-up web-browser
B) because you didin't do it right
p.s. it worked fine for me, using Firefox, Opera, or lynx.
Date: Sun, 11 Mar 2012 12:00:18 -0400
From: Bill Horne <bill@horneQRM.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: CenturyLink subscribers claims she had to pay previous tenant's bill
Message-ID: <4F5CCC12.5050304@horne.net>
Here's a new twist on debt collection: according to a complaint shown
below, CenturyLink has demanded that a new tenant pay the previous
tenant's bill in order to get phone service.
I call and order the basic $17.00 per month service and the line
backer for my life alert system. I am told I have to pay the
previous tenants bill before they will even talk to me. So I pay
that and get the service ordered ...
Rest is at
http://centurylink.pissedconsumer.com/century-link-sucks-20120309303584.html
Bill
--
Bill Horne
(Remove QRM from my address to write to me directly)
Date: Sun, 11 Mar 2012 12:55:42 -0400
From: Bill Horne <bill@horneQRM.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Complaint about Fairpoint internet speed
Message-ID: <jjilef$d45$1@dont-email.me>
I've been looking for dispassionate reports about the various former
baby bells and their offspring, but individual rants are much easier
to come by. This one concerns Fairpoint, which (among other things)
inherited Verizon's former Northern New England franchise.
Terrible Speed at Night
Every evening at about 5:00 pm my Fairpoint DSL speed drops from my
daily average of 6Mbps to 1.5 or less and stays at that speed till
about midnight.
http://www.dslreports.com/forum/r26839626-speed-latency-Terrible-Speed-at-Night
-or-
http://tinyurl.com/7hwftyd
Bill
--
Bill Horne
(Remove QRM from my address to write to me directly)
Date: 12 Mar 2012 04:06:52 GMT
From: Doug McIntyre <merlyn@geeks.org>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Complaint about Fairpoint internet speed
Message-ID: <4f5d765c$0$79795$8046368a@newsreader.iphouse.net>
Bill Horne <bill@horneQRM.net> writes:
>I've been looking for dispassionate reports about the various former
>baby bells and their offspring, but individual rants are much easier
>to come by. This one concerns Fairpoint, which (among other things)
>inherited Verizon's former Northern New England franchise.
> Terrible Speed at Night
> Every evening at about 5:00 pm my Fairpoint DSL speed drops from my
> daily average of 6Mbps to 1.5 or less and stays at that speed till
> about midnight.
That most likely means that they are probably on a remote DSLAM, and
it is too oversubscribed for the backhaul link. 5:00PM to Midnight
matches up perfectly with the peak residential usage hours for
Internet service.
Depending on the age of the remote, it could be one fed with ATM IMA T1s,
of which an 8 IMA T1 bundle is the best that they typically could do.
In the olden days, having 12Mbps feeding 24 1.5M DSL subscribers would
have been feasible. But if they have multiple 6-7Mbps customers on it,
come peak time, that isn't going to work so well.
About the only thing the LEC can do is get fiber uplink to that
remote, which can be quite an expensive propisition depending on the
circumstances.
Date: Sun, 11 Mar 2012 22:03:43 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Is the Philadelphia Cell Phone Jammer a Hero or Pest?
Message-ID: <MPG.29c7238b726b6961989d36@news.eternal-september.org>
In article <jjahum$dlm$1@panix2.panix.com>, kludge@panix.com says...
> From my perspective, I don't care if cellphones get jammed. I
> boggle that people trust them for emergency communications in the
> first place. However, the cellphone jammers cause a lot of
> collateral damage. I have seen several instances where they have
> caused interference to 950 Mhz broadcast auxiliary services.
>
> The cheap jammers sold on ebay and dealextreme are just broadband
> noise sources that cover the cellular bands and sadly they cover a
> whole lot of other stuff as well.
>
> The smart way to jam cellphones is to pretend to be a cell tower.
> You advertise a connection, then you refuse to complete a call. This
> can be done with very low power levels (probably levels legal under
> Part 15 even) and very effectively. Unfortunately nobody makes a
> cheap device to do this, although it's only a matter of time.
This brings up an interesting point about emergency communications. The
Providence, RI police department recently upgraded their radio systems.
By "recent", I mean within the last few years.
A couple [of] weeks ago I was at the West Broadway Neighborhood Association
meeting [where] Bill Trinque, Director of Commuications, [was] presenting.
He handed out a presentation and I start paging through [it]. I noticed that
their new trunked radio system is APCO P25 compliant.
Some time ago, HackADay had posted a video on how P25 was hacked with a
IM-Me(1) toy and a power amplifier. What it does is break the encryption so
they're forced to transmit in the clear.
Better yet, with a Software Defined Radio (SDR) you can actualy get
right on the APCO P25 systems and shut them down.
Now SDR's arent' cheap. But recent developments have implemented a n SDR
in a Field Programmable Gate Array (FPGA). So the price has dropped and
you can render emergency comms useless with < $200 worth of gear.
So there is no secure radio system for public safety that hasn't been
fully compromised.
It all gets down to marketing. I'm sure Motorola made claims of the
security of APCO P25 and the comms and police guys just ate it up.
***** Moderator's Note *****
This subject covers a wide area, and some of it is outside the telecom
range. However, it is important to realize that cell phones aren't
nearly as reliable as some people think.
The point is that our public safety radio systems and the cellular
network both depend on an environment without deliberate jamming,
DOS attacks, or simple eavesdropping: in other words, they depend on
everyone being willing to play nice. This lack of surviveability is
going to become a greater issue as time goes by, because lawbreakers
of all kinds will find the weaknesses and exploit them to disable cell
phones or Public Safety radios.
The intense reaction I got after my previous note on the subject of
the Philadelphia jammer points out a central failing in the cellular
networks, and that is that cellular users are assuming that radio
transceivers are as reliable as wireline phones. That's just not true,
and cellular customers need to prepare for failures of their phones,
or of the cellular system, if they are to have reliable access to help
in an emergency.
1. The "IM-Me" toy appears to be a short-range radio device that
allows children to send and receive instant messages through a home
computer.
The site that describes the "Denial of Service" attack is at
http://hackaday.com/2011/08/18/project-25-digital-radios-law-enforcemnet-grade-vulnerable-to-the-im-me/
-or-
http://goo.gl/naLzB
Bill Horne
Moderator
Date: Sun, 11 Mar 2012 22:03:06 -0500
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Note to Self: Siri Not Just Working for Me, Working Full-Time for Apple, Too
Message-ID: <p0624082ccb8310c6081b@[10.0.1.3]>
Note to Self: Siri Not Just Working for Me, Working Full-Time for Apple, Too
March 10, 2012
It came as a surprise to some folks at a recent SXSW talk that
Apple's Siri "personal assistant" isn't just working for us, it's
working full-time for Apple too by sending lots of our personal voice
and user info to Apple to stockpile in its databases. Take a peek at
Siri's privacy policy (which, by the way, is pretty difficult to
find) and you'll realize what's happening behind the scenes.
What info of yours is being collected and how is it being used? When
you use Siri, it's sending your "Voice Input Data" and "User Data" to
Apple to be used for a variety of purposes.
Voice Input Data is all the types of data associated with your verbal
commands and may also include audio recordings, transcripts of what
you said, and related diagnostic data. Apple says this Voice Input
Data is being used to process your request and to help Siri better
recognize your commands, but it's additionally being used "generally
to improve the overall accuracy and performance of Siri and other
Apple products and services."
Siri also collects "User Data" that it says gives it more context for
your commands, like what you mean by "Call Dad." This information can
be pretty wide-ranging:
* The names of your address book contacts, their nicknames, and their
relationship with you (for example, "my dad", or "work")
* Your first name and nickname
* Labels you assign to your email accounts (for example, "My Home Email")
* Names of songs and playlists in your collection
...
http://www.aclu.org/blog/free-speech-technology-and-liberty/note-self-siri-not-just-working-me-working-full-time-apple
Date: Sun, 11 Mar 2012 22:03:06 -0500
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Mini review: iPhones get a charge from Third Rail
Message-ID: <p06240832cb83153d1426@[10.0.1.3]>
Mini review: iPhones get a charge from Third Rail
By Sean Gallagher
One of the downsides to all of the WiFi connectivity,
location-sensing, and general usefulness of Apple's iPhone 4S is how
fast it draws down its battery. Unlike almost all of the other
touch-screen phones on the market, there's no way to swap in a spare
battery so you can extend your Netflix viewing another hour or two
when you're stuck in an airport, train station, or boring staff
meeting. But a set of products from a Florida company called Third
Rail Mobility make it possible to give your iPhone-or any other
device that can charge from a USB port-a recharge on the go.
Third Rail provided me with a test unit of the company's Third Rail
System for iPhone 4 and 4S, a $90 kit which consists of a slimline
case for the phone, an external battery that slides onto the back of
the case, and a set of cables that can be used to charge the phone
and battery, as well as charge other devices off of the battery. I've
been testing the case and battery over the last few weeks to see how
well they work for the worst-case scenario of usage: a series of
untethered workdays and weekends.
The Third Rail case itself, available on its own for $40, is a
two-piece black plastic shell that slightly lengthens the profile of
the iPhone. As iPhone cases go, it's not completely unattractive,
with its black matte finish; its extra length accommodates the
internal docking adapter that allows it to charge the phone from the
external battery.
...
http://arstechnica.com/apple/reviews/2012/03/getting-a-charge-for-iphones-with-third-rail.ars
Date: Sun, 11 Mar 2012 22:03:06 -0500
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: The iOS 5.1 update, "4G", AT&T, and the 3G Toggle
Message-ID: <p06240834cb8317709807@[10.0.1.3]>
The iOS 5.1 update, "4G", AT&T, and the 3G Toggle
by Brian Klug on 3/7/2012
AnandTech
When the iPhone 4S first launched, AT&T ominously noted (through a
document leaked to The Verge) that it was "working with Apple" to
update the 3G indicator to 4G in the status bar. Back then, the
extent of just how much AT&T was working with Apple on a regular
basis to both build carrier.ipcc bundles and beyond was unknown, but
the two have worked together in the past to make UI related changes,
going all the way back to the iPhone 3G's signal to bars mapping. In
addition, obviously the carrier works with Apple to both validate
baseband behavior and respective updates. However, having the carrier
dictate changes to UI seemed like new territory.
With respect to the iPhone 4S there was also some confusion about
whether the device was HSPA+, and whether that met ITU-R's earlier 4G
definitions. All of that we addressed in another post that I'd
encourage you to take a look at as a primer for all this. I'm not
going to go into that whole debate again since honestly the "4G"
thing boils down to a matter of definition, and whether or not you
subscribe to ITU-R or not is a matter of principle.
...
http://www.anandtech.com/show/5659/the-ios-51-update-4g-att-and-the-3g-toggle
TELECOM Digest is an electronic journal devoted mostly to telecom-
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