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Message Digest
Volume 28 : Issue 167 : "text" Format
Messages in this Issue:
Re: ANI vs. Caller ID (fwd)
Re: ANI vs. Caller ID
Re: ANI vs. Caller ID
Re: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Polarity reversal was Re: Touch Tone Charges - Bell Canada
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Re: 5XB arcana
Re: 5XB arcana
Re: 5XB arcana
Re: 5XB arcana
Re: 5XB arcana
Re: 5XB arcana
Re: ANI vs. Caller ID
Re: Pulse dialing overhead, was: ANI vs. Caller ID
Re: 4-/10-party lines
Re: 4-/10-party lines
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----------------------------------------------------------------------
Date: Fri, 19 Jun 2009 16:58:13 +1000
From: David Clayton <dcstar@myrealbox.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: ANI vs. Caller ID (fwd)
Message-ID: <pan.2009.06.19.06.58.12.491930@myrealbox.com>
On Thu, 18 Jun 2009 23:50:24 -0400, Adam H. Kerman wrote:
........
> There's no deception if one hasn't revealed his identity, which is all
> that's happened if someone blocks Caller ID or inputs an invalid phone
> number into the field.
>
> If you call me without telling me your name, you haven't deceived me. If
> you call me, stating that your name is Fred Willard but your name is
> actually John Drake, you have deceived me.
>
> If you call me, state that your name is Fred Willard, representative of
> Xerox, to sell me a photocopier maintenance service on my machine, but you
> don't work for Xerox, that's fraud.
Deception for the purpose of gaining an advantage from someone - as in
providing a false identity to circumvent any system designed to control
access to all but specifically identified individuals - *is* fraud.
If identity is the key to access (as CLID can be), then changing that
identity to obtain access is clearly fraudulent.
--
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: Fri, 19 Jun 2009 23:22:08 +0000 (UTC)
From: "Adam H. Kerman" <ahk@chinet.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: ANI vs. Caller ID
Message-ID: <h1h6iv$48f$1@news.albasani.net>
David Clayton <dcstar@myrealbox.com> wrote:
>On Thu, 18 Jun 2009 23:50:24 -0400, Adam H. Kerman wrote:
>>There's no deception if one hasn't revealed his identity, which is all
>>that's happened if someone blocks Caller ID or inputs an invalid phone
>>number into the field.
>>If you call me without telling me your name, you haven't deceived me. If
>>you call me, stating that your name is Fred Willard but your name is
>>actually John Drake, you have deceived me.
>>If you call me, state that your name is Fred Willard, representative of
>>Xerox, to sell me a photocopier maintenance service on my machine, but you
>>don't work for Xerox, that's fraud.
>Deception for the purpose of gaining an advantage from someone - as in
>providing a false identity to circumvent any system designed to control
>access to all but specifically identified individuals - *is* fraud.
>If identity is the key to access (as CLID can be), then changing that
>identity to obtain access is clearly fraudulent.
No, it is not clearly fraudulent. If all that has taken place is
misrepresentation of identity, then it's just deception. There are
situations independent of fraud in which deception in and of itself is a
criminal act. Fraud and deception often go hand in hand, but they are
two different acts.
If you call me, getting around my secretary by claiming to be someone
whose call I would accept, that's deception, not fraud. Until you offer
to sell me an item you do not own or a service you don't provide, you
haven't committed fraud.
------------------------------
Date: Fri, 19 Jun 2009 21:43:28 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: ANI vs. Caller ID
Message-ID: <9ddcde3b-212a-43ea-b7f9-bb02e16b6700@e20g2000vbc.googlegroups.com>
On Jun 19, 8:05 pm, "Adam H. Kerman" <a...@chinet.com> wrote:
> No, it is not clearly fraudulent. If all that has taken place is
> misrepresentation of identity, then it's just deception. There are
> situations independent of fraud in which deception in and of itself is a
> criminal act. Fraud and deception often go hand in hand, but they are
> two different acts.
Whether it's "fraud" or "deception" or just plain "rudeness" is
irrelevent.
Laws have been already passed to protect telephone subscribers, such
as regulations on sales solicitations, even when everything is totally
above-board.
IMHO, spoofing caller-id ought to be illegal. I can't imagine anyone
would be against something like that except for their own selfish
reasons. If they don't want others to see their real number, then
block it (a convenient free service).
Someone mentioned a "woman's shelter". If confidentiality is so
important, block the calls. Or, put in a generic phone line with some
B/S name and use that for outgoing calls.
***** Moderator's Note *****
Battered Women's shelters are a special case because some abusers are
cops or firefighters who have access to Local Usage Detail records
("LUDs") which reveal the calling number even when CLID is blocked.
As I wrote previously, it's common to falsify the records in such
cases, with or without help from the LEC.
------------------------------
Date: Fri, 19 Jun 2009 07:00:59 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: ANI vs. Caller ID
Message-ID: <6325bb4a-7c8f-4f97-929e-75f06081b2f1@v4g2000vba.googlegroups.com>
On Jun 17, 10:32 pm, Wesr...@aol.com wrote:
> > I think the Federal Trade Commission ought to order that the
> > carriers block spoofing on the grounds it is fraud. It's no
> > different than when the FTC orders a company to stop deceptive
> > advertising.
>
> How about the privacy of communications? I don't really want my
> carrier or ISP from looking into my private affairs, which they have
> to do to see what is going on.
There would be no need for a carrier or ISP to look into your
affairs. You have an assigned telephone number and directory name,
and that is to be transmitted. If you don't want that stuff
transmitted to those you call, you may block such transmission at no
charge. Blocking may be applied on a per call basis or on a all-call
basis.
------------------------------
Date: Fri, 19 Jun 2009 06:56:20 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <3fe77549-b757-4f72-988f-ec53fa04208c@n8g2000vbb.googlegroups.com>
On Jun 18, 11:45 pm, Wesr...@aol.com wrote:
> ***** Moderator's Note *****
>
> Were all trunks revertive? I thought #1XB was able to use MF
> signalling.
I'll try to find my Bell Labs book to answer that.
In Bell Telephone literature, the No. 1 crossbar seems to be the
forgotten step child. The articles always wax poetic about how the
No. 5 crossbar was able to be modified to handle another new service
or need; but the No. 1 is never mentioned.
The literature does describe the differences between the No. 1 and No.
5, but it's in technical terms--different functions were moved to
different parts of the machine. But not described is how those
differences affected actual operating functionality, maintainability,
and reliability. I can't help but wonder if perhaps the No. 1 didn't
perform that well. Indeed, only ten years after it entered service
they brought out the much touted No. 5., though the No. 5 was intended
more for larger suburban offices, not big city offices.
I also wonder which was retired last--No. 1 crossbar or Panel.
------------------------------
Date: Fri, 19 Jun 2009 23:04:20 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <2260d$4a3c5fc5$4aded8bf$12917@EVERESTKC.NET>
hancock4@bbs.cpcn.com wrote:
> On Jun 18, 11:45 pm, Wesr...@aol.com wrote:
>
>
>> ***** Moderator's Note *****
>>
>> Were all trunks revertive? I thought #1XB was able to use MF
>> signalling.
>>
> I'll try to find my Bell Labs book to answer that.
>
> In Bell Telephone literature, the No. 1 crossbar seems to be the
> forgotten step child. The articles always wax poetic about how the
> No. 5 crossbar was able to be modified to handle another new service
> or need; but the No. 1 is never mentioned.
>
> The literature does describe the differences between the No. 1 and No.
> 5, but it's in technical terms--different functions were moved to
> different parts of the machine. But not described is how those
> differences affected actual operating functionality, maintainability,
> and reliability. I can't help but wonder if perhaps the No. 1 didn't
> perform that well. Indeed, only ten years after it entered service
> they brought out the much touted No. 5., though the No. 5 was intended
> more for larger suburban offices, not big city offices.
>
> I also wonder which was retired last--No. 1 crossbar or Panel.
1XB outlasted Panel.
1XB also outlasted some 5XB switches. It was a heavy-hitter, while 5XB
would lock up.
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
------------------------------
Date: Fri, 19 Jun 2009 07:20:52 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <956af37a-13a7-4d99-9d0f-cc5b7fc1690f@l28g2000vba.googlegroups.com>
P.S.
On Jun 18, 10:19 am, hanco...@bbs.cpcn.com wrote:
> . . Usually that "event" is lifting the receiver to make or answer
> a call, or hanging up to terminate a call. But it can also be dial
> pulses. Software handles this, just as software handles the
> difference between wanting to make a call or answering a call (both
> initiated by going off hook, but are two different situations.)
I forgot to mention another common switchook DC signal "event" that
must be timed is subscriber flashing, such as for call waiting or 3-
way calling.
I was curious as to how many instructions a computer could execute
while someone keys in a phone number. I wrote a little QBASIC program
to count up executed instructions while I keyed in a number. Even
keying as fast as possible the computer was still able to do 1,000,000
simple instructions (a counter increment)! (And those are Quick Basic
instructions on a PC, which are not very efficient; a phone switch
could do much more.)
Anyway, the point is that, dial pulse or Touch Tone, an ESS switch is
doing plenty of other things during the time a human is dialing. Even
in the early days it 'time shared'. It is not 'tied up' or waiting
around; it is doing other things. Further, ESS, has front end
processors to handle I/O needs.
------------------------------
Date: Fri, 19 Jun 2009 14:28:15 -0500
From: bonomi@host122.r-bonomi.com (Robert Bonomi)
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <iuCdnQ1C9_pSe6bXnZ2dnUVZ_sGdnZ2d@posted.nuvoxcommunications>
In article <956af37a-13a7-4d99-9d0f-cc5b7fc1690f@l28g2000vba.googlegroups.com>,
<hancock4@bbs.cpcn.com> wrote:
> P.S.
>
> On Jun 18, 10:19 am, hanco...@bbs.cpcn.com wrote:
>
>> . . Usually that "event" is lifting the receiver to make or answer
>> a call, or hanging up to terminate a call. But it can also be dial
>> pulses. Software handles this, just as software handles the
>> difference between wanting to make a call or answering a call (both
>> initiated by going off hook, but are two different situations.)
>
>I forgot to mention another common switchook DC signal "event" that
>must be timed is subscriber flashing, such as for call waiting or 3-
>way calling.
>
>I was curious as to how many instructions a computer could execute
>while someone keys in a phone number. I wrote a little QBASIC program
>to count up executed instructions while I keyed in a number. Even
>keying as fast as possible the computer was still able to do 1,000,000
>simple instructions (a counter increment)! (And those are Quick Basic
>instructions on a PC, which are not very efficient; a phone switch
>could do much more.)
>
>Anyway, the point is that, dial pulse or Touch Tone, an ESS switch is
>doing plenty of other things during the time a human is dialing. Even
>in the early days it 'time shared'. It is not 'tied up' or waiting
>around; it is doing other things. Further, ESS, has front end
>processors to handle I/O needs.
>
Lets run some numbers for a big switch. 10,000 lines per prefix, the switch
handles 5 prefixes, (50,000) lines. To reliably detect 20PPS dialing requires
a minimum of 80 samples/line/second. 4,000,000 samples/second. scan logic
resembles:
top_of_loop:
compute address of status port, for this line
compute address of 'prior data value' for this line
read value from port
compare to prior data value
if changed jump to 'service' label
if have changes jump to 'digit' label
loop_end:
increment line id value
if less than max_line_id
go to top_of_loop label
set line id value to zero
go to top_of_loop label
service:
get time-tick from system clock/counter
save as last_service_time this line
go to loop_end label
digit:
get time-tick from system clock/counter
compute current_tick - last_service_tick this line
if (difference < inter-digit_min)
go to loop_end label
end-of-digit:
count state changes
divide by 2,
compute 'next digit address
store next digit
go to loop_end label
This example _grossly_ understates the clock cycles required,
but we're still looking at around 80 million instructions/second.
For starters, one wants the scan rate at least 50% higher, and to get two
instances of the 'new' signal level, before regarding it as 'changed'.
plus the logic for testing 'current' against 'last current', before
jumping to the 'service' label. Probably closer to 200 million instructions/
second.
That's 20% of a '1 _billion_ instructions'/second processor, being consumed
regardless, even if _nobody_ is doing anything.
If one assumes that off-hook is detected by hardware, which generates an
interrupt, and that the pulse scanning logic is activated only then, and
stays active for 20 seconds , with a switch-wide average of 20 outgoing
calls/day/line, the scanner is active for a total of 400 seconds/line,
instead of 86,400.
Assume that the interrupt service overhead is 40 instructions (_way_ high),
and you've reduced the CPU 'overhead' load from 20% of capacity to 0.20% of
capacity.
[Moderator snip]
------------------------------
Date: Fri, 19 Jun 2009 19:29:18 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <1d4c87b9-bb0f-44b9-9382-8f222d1de402@z7g2000vbh.googlegroups.com>
On Jun 19, 4:08 pm, bon...@host122.r-bonomi.com (Robert Bonomi) wrote:
> Lets run some numbers for a big switch. 10,000 lines per prefix,
> the switch handles 5 prefixes, (50,000) lines. To reliably detect
> 20PPS dialing requires a minimum of 80 samples/line/second, [or]
> 4,000,000 samples/second. scan logic resembles:
FALSE TO FACT: Here's why:
1) Please explain how switchhook flashing is detected, and determined
to be a flash, not a new call. By your logic merely scanning for
flashing would overload the switch. Obviously it doesn't.
2) Not all lines of a switch can dial at the same time, only a small
proportion.
3) Testing for dial pulses would be done only for subscribers actually
dialing a call.
4) Some sort of scanning is still required for Touch Tone entry to
collect the digits.
5) If scanning (polling) is done, it is done by a separate signal
processor, not the CPU.
6) As the other poster described, probably scanning isn't done, but
processing handled by interrupts when either a switchhook or dial
pulse is transmitted.
7) Your description describes what a switch does _not_ do. More
helpful would be a quotation from a citable text on what the switch
does do. My source is a Bell Labs intro engineering & operations
textbook. With far slower CPUs, they managed to scan.
I don't understand what point you're trying to make with all of this.
As mentioned before, so few people make dial pulse calls the issue is
moot. The phone companies dumped party line service when it became a
burden to support; if dial was an equal burden it'd be long gone.
Indeed, it would COST MORE to elimiinate dial from the generics:
remember how everyone emphasized how much testing is necessary for ANY
change to the program. Pull out dial support and every function must
be retested. Not worth the time nor trouble nor risk.
[programming code snipped]
> If one assumes that off-hook is detected by hardware, which generates an
> interrupt, and that the pulse scanning logic is activated only then, and
> stays active for 20 seconds , with a switch-wide average of 20 outgoing
> calls/day/line, the scanner is active for a total of 400 seconds/line,
> instead of 86,400.
If interrupts are used, as we believe they are, there is no need to
scan at all. Generate an interrupt for each DC signal event. This
_must_ be done now to handle flashing and supervision.
> Assume that the interrupt service overhead is 40 instructions (_way_
> high), and you've reduced the CPU 'overhead' load from 20% of
> capacity to 0.20% of capacity.
Interrupts need not be handled by the CPU. Full sized ESS had signal
processors independent of the CPU to handle that. IBM mainframes have
channel processors independent of the CPU to handle Input/output
devices, and they handle I/O interrupts and intefaces. (Low end ESS
and mainframes intended for light duty had the CPU handle that stuff
to save money.)
***** Moderator's Note *****
The ILEC's didn't dump party lines: they simply withdrew the tariffs,
and then offered the same service as "Ringmate". This is a win/win: it
uses the equipment that would otherwise be idle, and gives parents a
chance to have a separate number for the kids at minimal cost.
I doubt a switch owner would remove equipment once installed, including
party line capabilities, but especially dial pulse: after all, there's
no telling when someone with a 554 set on the wall of their bomb
shelter will lock themselves in ...
------------------------------
Date: Fri, 19 Jun 2009 10:09:50 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <MPG.24a5663e4fd24e0c989a6a@reader.motzarella.org>
In article <cd4.4f4df3d3.376c5255@aol.com>, Wesrock@aol.com says...
>
> In a message dated 6/18/2009 9:19:41 AM Central Daylight Time,
> hancock4@bbs.cpcn.com writes:
>
> > ESS also has to deal with a variety of inter-office singalling
> > arrangements, which may include DC pulse transmissions and
> > signalling from other offices of an older design. Now today
> > everything is ESS but when these boxes came out there was still a
> > great deal of step and panel out there.
>
> I always found it somewhat amusing a No. 1 Crossbar office used
> revertive pulsing for signalling, even when commnicating with another
> 1XB office (each of them emulating a Panel Type office). Yes, there
> was a lot of Panel when 1XB came out.
If I'm not mistaken, even #5 Xbar had to be capable of revertive pulsing
as well as MF, et al.
A lot of Panel didn't disappear until the 1970's.
------------------------------
Date: Fri, 19 Jun 2009 23:05:07 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <21161$4a3c5ff4$4aded8bf$12917@EVERESTKC.NET>
T wrote:
> In article <cd4.4f4df3d3.376c5255@aol.com>, Wesrock@aol.com says...
>
>> In a message dated 6/18/2009 9:19:41 AM Central Daylight Time,
>> hancock4@bbs.cpcn.com writes:
>>
>>
>>> ESS also has to deal with a variety of inter-office singalling
>>> arrangements, which may include DC pulse transmissions and
>>> signalling from other offices of an older design. Now today
>>> everything is ESS but when these boxes came out there was still a
>>> great deal of step and panel out there.
>>>
>> I always found it somewhat amusing a No. 1 Crossbar office used
>> revertive pulsing for signalling, even when commnicating with another
>> 1XB office (each of them emulating a Panel Type office). Yes, there
>> was a lot of Panel when 1XB came out.
>>
>
> If I'm not mistaken, even #5 Xbar had to be capable of revertive pulsing
> as well as MF, et al.
>
> A lot of Panel didn't disappear until the 1970's.
5XB could RP, MF and DP, in and out.
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
------------------------------
Date: Fri, 19 Jun 2009 10:08:59 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <MPG.24a5660850cc7920989a69@reader.motzarella.org>
In article <d18b2e3c217a04b268ee33b045d32a5a@192.168.222.4>,
jwillis.removethis@drlogick.com says...
>
> These days, pulse dialing costs more, because they have to stick an
> additional 'pulse to DTMF converter' on the front of the line before
> the call hits the DTMF-only switch. [This is not done] in Bell Canada
> Territory - they do the reverse, [and] filter out Touch-Tone if you
> are on a grandfathered rotary dial line.
For many years Ma Bell used to just reverse the line polarity so Touch
Tone dials wouldn't work. Of course if you knew about this you simply
[flipped] the pair at the demarc.
***** Moderator's Note *****
The Touch-Tone pads on WECO instruments could be disabled by reversing
tip and ring, but those of other manufacturers didn't seem to
care. Does anyone know why this was so? Was WECO's Touch-Tone pad
designed for it, or was that a by product that became a feature?
------------------------------
Date: Fri, 19 Jun 2009 19:21:58 +0000 (UTC)
From: David Lesher <wb8foz@panix.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <h1gogm$t87$1@reader1.panix.com>
>***** Moderator's Note *****
>The Touch-Tone pads on WECO instruments could be disabled by reversing
>tip and ring, but those of other manufacturers didn't seem to
>care. Does anyone know why this was so? Was WECO's Touch-Tone pad
>designed for it, or was that a by product that became a feature?
It was a consequence of that extra-special pad design. It saved money by
having only one of those expensive transistors.
True, it had two tapped cup-core inductors, and was hand tuned; but we
all know transistors are expensive!
--
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: Fri, 19 Jun 2009 17:31:54 -0400
From: Bill Horne <bill@horneQRM.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <goidnc2zWqRXnqHXnZ2dnUVZ_oCdnZ2d@speakeasy.net>
David Lesher wrote:
>> ***** Moderator's Note *****
>
>> The Touch-Tone pads on WECO instruments could be disabled by reversing
>> tip and ring, but those of other manufacturers didn't seem to
>> care. Does anyone know why this was so? Was WECO's Touch-Tone pad
>> designed for it, or was that a by product that became a feature?
>
>
>
> It was a consequence of that extra-special pad design. It saved money by
> having only one of those expensive transistors.
>
> True, it had two tapped cup-core inductors, and was hand tuned; but we
> all know transistors are expensive!
The odd thing with WECO pads was that the inductors had a tap for the
fourth column tones that were usually used only on AUTOVAN phones: the
fourth column on those pads was for the military precedence levels.
Since the tap was there already, many hams used it to add a column to
their pads, which they needed for control of ham repeater stations.
Bill, W1AC
------------------------------
Date: Fri, 19 Jun 2009 22:27:35 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <MPG.24a613219b53237f989a74@reader.motzarella.org>
In article <goidnc2zWqRXnqHXnZ2dnUVZ_oCdnZ2d@speakeasy.net>,
bill@horneQRM.net says...
>
> David Lesher wrote:
> >> ***** Moderator's Note *****
> >
> >> The Touch-Tone pads on WECO instruments could be disabled by reversing
> >> tip and ring, but those of other manufacturers didn't seem to
> >> care. Does anyone know why this was so? Was WECO's Touch-Tone pad
> >> designed for it, or was that a by product that became a feature?
> >
> >
> >
> > It was a consequence of that extra-special pad design. It saved money by
> > having only one of those expensive transistors.
> >
> > True, it had two tapped cup-core inductors, and was hand tuned; but we
> > all know transistors are expensive!
>
> The odd thing with WECO pads was that the inductors had a tap for the
> fourth column tones that were usually used only on AUTOVAN phones: the
> fourth column on those pads was for the military precedence levels.
> Since the tap was there already, many hams used it to add a column to
> their pads, which they needed for control of ham repeater stations.
>
> Bill, W1AC
Yep - I had an old red 2500 set with a toggle switch. Flipping it would
toggle the rightmost column from 3,6,7,# to the F, FO, P etc.
frequencies.
------------------------------
Date: Fri, 19 Jun 2009 18:07:21 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <MPG.24a5d628168f99c8989a6f@reader.motzarella.org>
In article <h1gogm$t87$1@reader1.panix.com>, wb8foz@panix.com says...
>
> >***** Moderator's Note *****
>
> >The Touch-Tone pads on WECO instruments could be disabled by reversing
> >tip and ring, but those of other manufacturers didn't seem to
> >care. Does anyone know why this was so? Was WECO's Touch-Tone pad
> >designed for it, or was that a by product that became a feature?
>
>
>
> It was a consequence of that extra-special pad design. It saved money by
> having only one of those expensive transistors.
>
> True, it had two tapped cup-core inductors, and was hand tuned; but we
> all know transistors are expensive!
Actually the single transistor was a brillian design, it acts as a
simple amplifier and then uses an LC tank to generate the frequencies,
hence the two cup core inductors.
------------------------------
Date: Sat, 20 Jun 2009 03:06:24 +0000 (UTC)
From: David Lesher <wb8foz@panix.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <h1hjnf$ogo$2@reader1.panix.com>
T <kd1s.nospam@cox.nospam.net> writes:
>> It was a consequence of that extra-special pad design. It saved money by
>> having only one of those expensive transistors.
>>
>> True, it had two tapped cup-core inductors, and was hand tuned; but we
>> all know transistors are expensive!
>Actually the single transistor was a brillian design, it acts as a
>simple amplifier and then uses an LC tank to generate the frequencies,
>hence the two cup core inductors.
It was a brilliant design only when the transistor cost a few bucks, and
the magnetics didn't.
But a few years later it was 180 degrees around. But Ma/WECO kept making
the same pad for about 20 years....
--
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: Fri, 19 Jun 2009 19:08:12 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <e2961da0-b07a-4b4c-837c-b50d09e7d5f5@n30g2000vba.googlegroups.com>
On Jun 19, 4:03 pm, David Lesher <wb8...@panix.com> wrote:
> True, it had two tapped cup-core inductors, and was hand tuned; but we
> all know transistors are expensive!
To meet the very high service demands of the Bell System---which is
why 40 year old units still work perfectly fine today--they used very
high grade components. As they put it, the phone had to withstand
drops to a hard floor, a cold storage locker, and a hot humid sunny
window sill.
Further, 40 years ago high grade transistors were not cheap. Now
whether it was necessary to use such high-grade durable components is
tough to say. But since the Bell System owned the equipment and was
responsible for all maintenance, it was to their advantage to reduce
downtime and maximize the life of the equipment.
------------------------------
Date: Fri, 19 Jun 2009 14:57:11 -0700
From: Sam Spade <sam@coldmail.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <XQT_l.29892$IP7.25754@newsfe23.iad>
T wrote:
> In article <d18b2e3c217a04b268ee33b045d32a5a@192.168.222.4>,
> jwillis.removethis@drlogick.com says...
>
>>These days, pulse dialing costs more, because they have to stick an
>>additional 'pulse to DTMF converter' on the front of the line before
>>the call hits the DTMF-only switch. [This is not done] in Bell Canada
>>Territory - they do the reverse, [and] filter out Touch-Tone if you
>>are on a grandfathered rotary dial line.
>
>
> For many years Ma Bell used to just reverse the line polarity so Touch
> Tone dials wouldn't work. Of course if you knew about this you simply
> [flipped] the pair at the demarc.
>
>
> ***** Moderator's Note *****
>
> The Touch-Tone pads on WECO instruments could be disabled by reversing
> tip and ring, but those of other manufacturers didn't seem to
> care. Does anyone know why this was so? Was WECO's Touch-Tone pad
> designed for it, or was that a by product that became a feature?
>
A recollection, perhaps an incorrect one: In the early days (Ernestine
Days) of Touch-Tone, Ma Bell didn't want you to be able to send out
tones once answer supervision was present. Does this click with anyone?
------------------------------
Date: Fri, 19 Jun 2009 23:27:05 +0000 (UTC)
From: danny burstein <dannyb@panix.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <h1h6s9$4es$1@reader1.panix.com>
In <XQT_l.29892$IP7.25754@newsfe23.iad> Sam Spade <sam@coldmail.com> writes:
>A recollection, perhaps an incorrect one: In the early days (Ernestine
>Days) of Touch-Tone, Ma Bell didn't want you to be able to send out
>tones once answer supervision was present. Does this click with anyone?
In the NYC area at least, as late as 1980 or so (I didn't use
this later) a "toll call" would cause a current reversal
as the connection was being processed. So.... if you placed
a diode in series with the phone line, the person could
make "local" calls but no long distance (that is, they'd
get disconnected).
Incidentally, I discovered this when perusing the newspapers
and coming across one of those telco teensy print legal
notices. I don't recall the exact wording but it used the
term "battery reversal" (or maybe "battery current reversal")
for a tariff regarding toll blocking. It also stated that
the telco wouldn't be liable if the caller still got through..
Oh, and for a[n] historically interesting advert of this sort,
check out a scan I made nearly 2 decades ago:
http://www.dburstein.com/images/nat-sec.png
--
_____________________________________________________
Knowledge may be power, but communications is the key
dannyb@panix.com
[to foil spammers, my address has been double rot-13 encoded]
------------------------------
Date: Fri, 19 Jun 2009 18:58:47 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Polarity reversal was Re: Touch Tone Charges - Bell Canada
Message-ID: <566f2f00-baea-4130-9289-57dd08699ee8@l34g2000vbi.googlegroups.com>
On Jun 19, 8:14 pm, danny burstein <dan...@panix.com> wrote:
> In the NYC area at least, as late as 1980 or so (I didn't use
> this later) a "toll call" would cause a current reversal
> as the connection was being processed. So.... if you placed
> a diode in series with the phone line, the person could
> make "local" calls but no long distance (that is, they'd
> get disconnected).
According to both an AE catalog and a Bell text, it was standard
practice for a Step by Step swtich to reverse polarity after the
call went through.
For semi-post-pay public phones, this was necessary to set the magnet
switch to block the transmitter until a coin was dropped. But beyond
that, I don't understand why they'd reverse polarity.
Sam Spade <s...@coldmail.com> Fri, 19 Jun 2009 19:06:19 -0400 (EDT)
wrote:
>A recollection, perhaps an incorrect one: In the early days (Ernestine
>Days) of Touch-Tone, Ma Bell didn't want you to be able to send out
>tones once answer supervision was present. Does this click with anyone?
I doubt that's correct. We had Touch Tone in that era and it would
send tones during the course of the phone (which the other party did
not appreciate since they were loud).
Touch Tone sounds were very carefully chosen to avoid sounding like
human tones or other internal system tones that they could be confused
with.
But very early on Bell pushed the idea of connecting to computers via
TT phones. In those days our bank staff used a TT pad to contact
their computer. (It was a separate pad since the neighborhood itself
hadn't gone TT yet so the phone still had a dial on it.)
------------------------------
Date: Sat, 20 Jun 2009 03:07:59 +0000 (UTC)
From: David Lesher <wb8foz@panix.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <h1hjqf$ogo$3@reader1.panix.com>
Sam Spade <sam@coldmail.com> writes:
>A recollection, perhaps an incorrect one: In the early days (Ernestine
>Days) of Touch-Tone, Ma Bell didn't want you to be able to send out
>tones once answer supervision was present. Does this click with anyone?
Reversal on supervision was a function of the CO. As I recall,
most step-offices did, but XB did not. I don't recall about panel.
Of course coil phone lines DID reverse...
--
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: Fri, 19 Jun 2009 18:06:30 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <MPG.24a5d5f0a5d1970a989a6e@reader.motzarella.org>
In article <MPG.24a5660850cc7920989a69@reader.motzarella.org>,
kd1s.nospam@cox.nospam.net says...
>
> In article <d18b2e3c217a04b268ee33b045d32a5a@192.168.222.4>,
> jwillis.removethis@drlogick.com says...
> >
> > These days, pulse dialing costs more, because they have to stick an
> > additional 'pulse to DTMF converter' on the front of the line before
> > the call hits the DTMF-only switch. [This is not done] in Bell Canada
> > Territory - they do the reverse, [and] filter out Touch-Tone if you
> > are on a grandfathered rotary dial line.
>
> For many years Ma Bell used to just reverse the line polarity so Touch
> Tone dials wouldn't work. Of course if you knew about this you simply
> [flipped] the pair at the demarc.
>
>
> ***** Moderator's Note *****
>
> The Touch-Tone pads on WECO instruments could be disabled by reversing
> tip and ring, but those of other manufacturers didn't seem to
> care. Does anyone know why this was so? Was WECO's Touch-Tone pad
> designed for it, or was that a by product that became a feature?
I don't know if it was a feature WECO produced sets. But the initial
Touch Tone sets most definitely had thier T/R swapped. If a Bell
installer was putting one in a home he'd swap the incoming pair.
Later sets dropped the polarity guard entirely since they were going to
be sold directly to customers.
------------------------------
Date: Fri, 19 Jun 2009 22:50:21 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <4d5fa$4a3c5c7f$4aded8bf$7248@EVERESTKC.NET>
T wrote:
> In article <d18b2e3c217a04b268ee33b045d32a5a@192.168.222.4>,
> jwillis.removethis@drlogick.com says...
>
>> These days, pulse dialing costs more, because they have to stick an
>> additional 'pulse to DTMF converter' on the front of the line before
>> the call hits the DTMF-only switch. [This is not done] in Bell Canada
>> Territory - they do the reverse, [and] filter out Touch-Tone if you
>> are on a grandfathered rotary dial line.
>>
>
> For many years Ma Bell used to just reverse the line polarity so Touch
> Tone dials wouldn't work. Of course if you knew about this you simply
> [flipped] the pair at the demarc.
>
>
> ***** Moderator's Note *****
>
> The Touch-Tone pads on WECO instruments could be disabled by reversing
> tip and ring, but those of other manufacturers didn't seem to
> care. Does anyone know why this was so? Was WECO's Touch-Tone pad
> designed for it, or was that a by product that became a feature?
>
Many newer WECo telsets or pads had a "Polarity Guard" which was
basically a full-wave (bridge) rectifier.
Line polarity had become a big problem after Divestiture. Many people
were purchasing their phones at their local Five & Dime or drug store.
These were designed to work on unknown polarity because so many homes
were actually wired reversed.
http://www.ericofon.com/catalog/parts/pg.htm
Cable pairs were also reversed. What worked one day for someone on a
pair that had been reversed for years, would fail when the splicers made
a throw, or replaced a section of cable.
Sadly, some employees were not as well trained as those from yesteryear,
and their supervisors also couldn't care less.
Here's a good site with telset wiring diagrams:
http://www.telephonecollectors.org/library/weco/weco.htm
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
------------------------------
Date: Fri, 19 Jun 2009 09:21:56 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Touch Tone Charges - Bell Canada Still Charges Extra $2.80 a month
Message-ID: <8cc2df13-6b57-4d15-b1b7-42aa1c77cfe8@21g2000vbk.googlegroups.com>
On Jun 18, 11:25 pm, jwillis <jwillis.removet...@drlogick.com> wrote:
> These days, pulse dialing costs more, because they have to stick an
> additional 'pulse to DTMF converter' on the front of the line before
> the call hits the DTMF-only switch.
There is considerable suspicion that no such "pulse to DTMF" converter
exists. A telephone switch must respond to DC signals (pulses)
because the hookswitch sends DC, so responding to DC pulses (such as a
subscriber flashing) is an integral part of the switch function.
Touch Tones are not digital, and must be converted into a form the
switch computer understands. Accordingly, there is no evidence that
pulse costs more. There's a separate ongoing long discussion in this
newsgroup on this issue you may wish to review. If you have technical
literature describing the "pulse to Touch Tone converter", could you
cite the book?
> Bell has grandfathered all rotary dial lines - if you dont move you
> dont have to pay the $2.80 a month for Touch-Tone, they put a filter
> on the line so that Touch-Tone will not dial out. If you move then
> Bell will start charging the $2.80 extra a month.
I do not think any "filter" is added to the line. Rather, the switch
software merely ignores Touch Tone signals from that subscriber. It's
no different than if you attempt to flash to get 3-way calling but
your line is not equipped for that, when you flash, nothing happens.
------------------------------
Date: Fri, 19 Jun 2009 07:10:32 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 5XB arcana
Message-ID: <d1eca9a6-7519-4804-ad65-a921a6c27112@n4g2000vba.googlegroups.com>
On Jun 18, 11:55 pm, Thad Floryan <t...@thadlabs.com> wrote:
> John Morse posted another interesting article in the Linux group
> which I've copy'n'pasted below. Email to him did not succeed, so I
> posted a one-liner in that group inviting him to comp.dcom.telecom;
> hopefully he'll join us.
Thanks for sharing the post. Interesting stuff.
> Was your 5XB one of the old original flat-spring models? Perhaps you
> also had an old SXS switch in the same building?
It was common in telephone buildings to have different switches of
different vintages.
> Two were wire-spring, but the oldest was a flat-spring model.
In the IBM history, there is mention of "wire spring relays" as being
a big improvement, and _possibly_ invented by IBM. I'm not sure what
they are and why they are superior. But apparently they allow
equipment to be smaller and work faster.
Compared to computers relays are slow, of course, but to the naked eye
watching a relay machine do its magic is fascinating. They're able to
do quite a few tasks very quickly. For instance, a step switch will
quickly hunt over terminals until it finds an empty one--that means
each terminal must be tested and the switch respond accordingly. Just
lifting a receiver in crossbar causes all sorts of things to happen
before dial tone comes.
> I went back many years later and noticed the 5XB AMA Translator
> frames were jam-packed with jumpers. Seems the Chief Switchman had
> gotten tired of so many 5-Tickets from lost revenue on toll calls,
> due to framemen pulling out the wrong jumpers, he ordered no more
> jumper removal on disconnect orders. That caused a gradual build-up
> of wire until the detecting loops were choked-full of wire. You
> could only unwrap and remove a Translator jumper when you had a new
> connect order for that Line Link assignment. But the framemen
> wouldn't pull out the wires, so the loops were packed with
> disconnected tangled wires.
This was one of the problems that led to the NYC service meltdown in
the 1970s. In that era, people began to move much more often
resulting in a high volume of installations and disconnections. They
didn't remove old jumpers from the MDF and it got badly overcrowded.
This all led to better MDF maintenance and record keeping practices.
------------------------------
Date: Sat, 20 Jun 2009 12:15:16 +1000
From: David Clayton <dcstar@myrealbox.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 5XB arcana
Message-ID: <pan.2009.06.20.02.15.15.398751@myrealbox.com>
On Fri, 19 Jun 2009 12:46:07 -0400, hancock4 wrote:
.........
> This was one of the problems that led to the NYC service meltdown in the
> 1970s. In that era, people began to move much more often resulting in a
> high volume of installations and disconnections. They didn't remove old
> jumpers from the MDF and it got badly overcrowded. This all led to better
> MDF maintenance and record keeping practices.
That sort of thing was not uncommon in Australia either, telco technicians
would get an order to cancel a service but just wouldn't bother to
actually do anything - resulting in old jumpers being left connected
all over the network which then slowed down new connections that were
allocated using that pair.
It also caused massive inefficient use of the infrastructure as it was
deemed "better" to leave something that "might" be cancelled in place
rather than go to the trouble of determining once and for all if that
resource was actually in use or not.
It was only when someone calculated the cost of this inefficiency (like
running new cables instead of using the actual available resources in the
existing stuff) that cleaning up old services and records was finally
taken seriously.
--
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: Fri, 19 Jun 2009 23:24:07 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 5XB arcana
Message-ID: <b945d$4a3c6467$4aded8bf$14574@EVERESTKC.NET>
hancock4@bbs.cpcn.com wrote:
> On Jun 18, 11:55 pm, Thad Floryan <t...@thadlabs.com> wrote:
>
>
>> John Morse posted another interesting article in the Linux group
>> which I've copy'n'pasted below. Email to him did not succeed, so I
>> posted a one-liner in that group inviting him to comp.dcom.telecom;
>> hopefully he'll join us.
>>
Can you hear me now? ;-)
> Thanks for sharing the post. Interesting stuff.
>
>
>> Was your 5XB one of the old original flat-spring models? Perhaps you
>> also had an old SXS switch in the same building?
>>
>
> It was common in telephone buildings to have different switches of
> different vintages.
>
>> Two were wire-spring, but the oldest was a flat-spring model.
>>
>
> In the IBM history, there is mention of "wire spring relays" as being
> a big improvement, and _possibly_ invented by IBM. I'm not sure what
> they are and why they are superior. But apparently they allow
> equipment to be smaller and work faster.
>
Smaller, faster, better contacts, cheaper, less current draw, etc.
The wire springs allowed a better contact "wipe" than the flat spring
relays. Kept the contacts cleaner, and probably knocked off pitting growth.
> Compared to computers relays are slow, of course, but to the naked eye
> watching a relay machine do its magic is fascinating. They're able to
> do quite a few tasks very quickly. For instance, a step switch will
> quickly hunt over terminals until it finds an empty one--that means
> each terminal must be tested and the switch respond accordingly. Just
> lifting a receiver in crossbar causes all sorts of things to happen
> before dial tone comes.
>
>
>> I went back many years later and noticed the 5XB AMA Translator
>> frames were jam-packed with jumpers. Seems the Chief Switchman had
>> gotten tired of so many 5-Tickets from lost revenue on toll calls,
>> due to framemen pulling out the wrong jumpers, he ordered no more
>> jumper removal on disconnect orders. That caused a gradual build-up
>> of wire until the detecting loops were choked-full of wire. You
>> could only unwrap and remove a Translator jumper when you had a new
>> connect order for that Line Link assignment. But the framemen
>> wouldn't pull out the wires, so the loops were packed with
>> disconnected tangled wires.
>>
>
> This was one of the problems that led to the NYC service meltdown in
> the 1970s. In that era, people began to move much more often
> resulting in a high volume of installations and disconnections. They
> didn't remove old jumpers from the MDF and it got badly overcrowded.
> This all led to better MDF maintenance and record keeping practices.
>
I visited the CEntral CO in Topeka, Kansas around 1970. That was a huge
Stroger SXS office, with the auxiliary line finders in wooden cabinets
with glass windows. I forget their actual name, but they appeared to
oscillate back and forth, left to right, with contacts somehow stopping
and held to terminals when a subscriber went ROH.
They had a very long MDF, which grew beyond the length of their building
(front corner to rear alley). So, they kept adding on to it after a
90-degree bend, and went across the rear of the building.
Over the years, the jumpers started falling and hanging off the shelves.
It was a big mess, even after they attempted to stop the spillage with
vertical 5/8" threaded rod covered with a plastic insulator.
I can't imagine the difficulty a frameman must have had running jumpers
on that MDF.
Another old Panel and 1XB office had an MDF with a balcony. I think the
horizontal shelves went clear up to "V" (lettered "A" through "V") where
a "normal" MDF had a top horizontal shelf "Q."
The balcony had stairs at both ends, and a switchback staircase around
the middle. Running a jumper might require visiting a vertical on both
levels. Seems we invented a (broomstick) pole with a hook to grab
jumpers to avoid all the leg work.
This MDF, by the way, was at the same height as most of the Panel
frames. Ladders were so tall you could get a nose bleed! ;-)
The newer 1XB switch had enough headroom above the cable racks that you
could easily walk upright without hitting the ceiling.
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
***** Moderator's Note *****
At the Back Bay office in Boston, the MDF went up to the "T" shelf.
Bill Horne
Temporary Moderator
------------------------------
Date: Fri, 19 Jun 2009 19:27:24 +0000 (UTC)
From: David Lesher <wb8foz@panix.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 5XB arcana
Message-ID: <h1goqs$t87$2@reader1.panix.com>
Thad Floryan <thad@thadlabs.com> writes:
>Was your 5XB one of the old original flat-spring models? Perhaps you
>also had an old SXS switch in the same building?
I was told a story by a friend in an operating company
about an early wire-spring 5XB. It was installed in Los
Angeles. True to form, the floor was swept regularly,
http://long-lines.net/documents/BSP-770-130-301/BSP-770-130-301-p1.html
so as to keep things ship-shape.
The switch died just a few months later. They found the LA smog was
corroding the wire springs, which then fell off....and were swept away
before anyone noticed....
WECO ended up junking the switch, and Bell Labs learned a lot about
corrosion in smog.
--
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: Fri, 19 Jun 2009 17:34:05 -0400
From: Bill Horne <bill@horneQRM.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 5XB arcana
Message-ID: <goidncyzWqTQmaHXnZ2dnUVZ_oCdnZ2d@speakeasy.net>
David Lesher wrote:
> Thad Floryan <thad@thadlabs.com> writes:
>
>
>> Was your 5XB one of the old original flat-spring models? Perhaps you
>> also had an old SXS switch in the same building?
>
>
> I was told a story by a friend in an operating company
> about an early wire-spring 5XB. It was installed in Los
> Angeles. True to form, the floor was swept regularly,
> http://long-lines.net/documents/BSP-770-130-301/BSP-770-130-301-p1.html
> so as to keep things ship-shape.
>
> The switch died just a few months later. They found the LA smog was
> corroding the wire springs, which then fell off....and were swept away
> before anyone noticed....
>
> WECO ended up junking the switch, and Bell Labs learned a lot about
> corrosion in smog.
I kinda doubt that. Even El-Lay smog couldn't do _that_ as fast as _that_.
I _might_ believe that the contacts needed more cleaning, but not that
they were falling off the relays.
Bill
------------------------------
Date: Fri, 19 Jun 2009 18:09:14 -0400
From: T <kd1s.nospam@cox.nospam.net>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 5XB arcana
Message-ID: <MPG.24a5d69380d48265989a70@reader.motzarella.org>
In article <h1goqs$t87$2@reader1.panix.com>, wb8foz@panix.com says...
>
> Thad Floryan <thad@thadlabs.com> writes:
>
>
> >Was your 5XB one of the old original flat-spring models? Perhaps you
> >also had an old SXS switch in the same building?
>
>
> I was told a story by a friend in an operating company
> about an early wire-spring 5XB. It was installed in Los
> Angeles. True to form, the floor was swept regularly,
> http://long-lines.net/documents/BSP-770-130-301/BSP-770-130-301-p1.html
> so as to keep things ship-shape.
>
> The switch died just a few months later. They found the LA smog was
> corroding the wire springs, which then fell off....and were swept away
> before anyone noticed....
>
> WECO ended up junking the switch, and Bell Labs learned a lot about
> corrosion in smog.
So if smog was eating away the wire springs imagine what it was doing to
the people. Nice to see CA now publishing data on 30 chemicals known to
be endocrine disruptors and carcinogens.
------------------------------
Date: Fri, 19 Jun 2009 23:29:36 +0000 (UTC)
From: "Adam H. Kerman" <ahk@chinet.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: ANI vs. Caller ID
Message-ID: <h1h70v$48f$2@news.albasani.net>
John David Galt <jdg@diogenes.sacramento.ca.us> wrote:
>Adam H. Kerman wrote:
>>The term "spoofing" has been used inaccurately throughout this subthread.
>>Caller-defined Caller-ID isn't spoofed unless a number has been input
>>that isn't a line number subscribed to at that call center's location
>>(or perhaps at another call center of that company). If another number
>>was input that's subscribed to by an unrelated telephone subscriber,
>>then spoofing rises to the level of forgery. And if it's done for the
>>purpose of initiating a scam, it's fraud.
>If it's done for the purpose of preventing you from successfully filtering
>out unwanted calls, that's fraud too. "Meaningless" numbers qualify, IMO.
There are victims of actual fraud, who were deceived into participating
in schemes resulting in the loss of property or possibly their life's
savings.
If you accept a call from a telemarketer failing to identify himself in
Caller ID, you are not a victim of fraud.
Please don't equate having had time wasted by a cold caller
with the loss of unaffordable amounts of property or cash.
------------------------------
Date: Fri, 19 Jun 2009 23:01:54 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Pulse dialing overhead, was: ANI vs. Caller ID
Message-ID: <c5cb2$4a3c5f32$4aded8bf$12917@EVERESTKC.NET>
Wesrock@aol.com wrote:
> In a message dated 6/18/2009 9:19:41 AM Central Daylight Time,
> hancock4@bbs.cpcn.com writes:
>
>
>> ESS also has to deal with a variety of inter-office singalling
>> arrangements, which may include DC pulse transmissions and
>> signalling from other offices of an older design. Now today
>> everything is ESS but when these boxes came out there was still a
>> great deal of step and panel out there.
>>
>
> I always found it somewhat amusing a No. 1 Crossbar office used
> revertive pulsing for signalling, even when commnicating with another
> 1XB office (each of them emulating a Panel Type office). Yes, there
> was a lot of Panel when 1XB came out.
>
>
> Wes Leatherock
> wesrock@aol.com
> wleathus@yahoo.com
>
>
> ***** Moderator's Note *****
>
> Were all trunks revertive? I thought #1XB was able to use MF
> signalling.
>
> Bill Horne
> Temporary Moderator
>
1XB could use RP, MF, DP and PCI.
Most used RP and MF, but DP was used if they connected directly to a SXS
CO, and there was no route through a tandem office.
It just depended on what "Dial Assignment" wanted to use to keep the
senders balanced, without needing to pay WECo to install something else.
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
------------------------------
Date: Fri, 19 Jun 2009 23:27:17 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 4-/10-party lines
Message-ID: <db70b$4a3c6526$4aded8bf$9907@EVERESTKC.NET>
Rich Greenberg wrote:
> In article <4A39F9A4.1020107@thadlabs.com>,
> Thad Floryan <thad@thadlabs.com> wrote:
>
> [...]
>
>
>> Yes, they each had their own "private" ringing, but only one of them
>> could use their phone at the same time, which is how any party line
>> works. The oddity is they each paid about 70% of what a "straight" line
>> would have cost, and only gained separate ringing.
>>
>> Since they lived in the same house, I though it would be easier, and
>> certainly cheaper, for any caller to simply ask for the opposite
>> roommate if they wanted them.
>>
>> Instead of paying a 140% telephone bill.
>>
>
> I would hazard a WAG that the elderly gents preferred getting 2 seperate
> bills, each with their own LD charges already seperated instead of one
> combined bill where they needed to seperate out who made this LD call.
>
Hmmm....
Never thought of that. My mind was on technology and not social finance
issues. ;-)
Good catch.
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
***** Moderator's Note *****
I think that sharing party lines might have been done a lot: I knew
two MIT students who did it, for exactly the reason that they got
separate bills, and also so they could tell who the call was for
without having to answer, a very nice benefit when LD charges were
really high and their families would call.
Even now, the Ringmate offering (which _is_ two party lines in one
home) comes in handy to tell "friends" apart from "everyone else",
so "party" lines will be with us for a while yet.
Bill Horne
Temporary Moderator
------------------------------
Date: Fri, 19 Jun 2009 23:31:27 -0500
From: "John F. Morse" <xanadu.bbs@example.invalid>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: 4-/10-party lines
Message-ID: <18293$4a3c6621$4aded8bf$10364@EVERESTKC.NET>
David Lesher wrote:
> hancock4@bbs.cpcn.com writes:
>
>
>> I'm not sure if Bell System 4 party phones required these gas tubes.
>> There were four ways of sending ringing current so 4-party phones
>> would be selectively rung. The Independents used a different system
>> (harmonics, as the post describes).
>>
>
> I know of no scheme of selective 4-party ringing that Ma used, except
> those the BSP described -- the gas tube system.
>
> Independents used three frequency-selective schemes:
>
> 22, 33, 44, 55, 66 Hz.
>
> 20, 30, 40, 50, 60 Hz.
>
> 16.66, 33.33, 50, 66.66 Hz.
>
> Which scheme they chose appears to have been a function of the kind of
> ring generator they had in the central office.
>
Those frequencies seem familiar.
My last association with harmonic and Decimonic ringers ended in 1968,
and I've slept since then. ;-)
I need to correct one statement I made though. The various weights were
not actually on the clapper arm, but an arm mounted directly below it,
which was also connected to the same armature.
I have one or two in old phones in boxes in the basement.
--
John
No Microsoft, Apple, AT&T, Novell, Trend Micro, nor Ford products were
used in the preparation or transmission of this message.
The EULA sounds like it was written by a team of lawyers who want to
tell me what I can't do. The GPL sounds like it was written by a human
being, who wants me to know what I can do.
***** Moderator's Note *****
John, please contact me offline: bill at horne dot net.
------------------------------
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