telecom@ucbvax.ARPA (05/18/85)
From: Jon Solomon (the Moderator) <Telecom-Request@BBNCCA>
TELECOM Digest Fri, 17 May 85 22:44:37 EDT Volume 4 : Issue 193
Today's Topics:
Call Waiting
Re: DTN
dumb question
Re: TELECOM Digest V4 #191 212 modem UUUU-echo
Re: Pay phone earpiece
Equal access idea
Telephone Innards
Close but .....
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Date: Tue 14 May 85 15:56:13-PDT
From: Moshe Y. Vardi <VARDI@SU-CSLI.ARPA>
Subject: Call Waiting
To: telecom@BBNCCA.ARPA
What happens when you have Call Waiting on a line that is connected to a modem.
Is it possible to take the call without disconnecting your remote session?
Moshe Vardi
Vardi@su-aimvax.arpa
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Date: Wednesday, 15 May 1985 08:44:22-PDT
From: herbison%ultra.DEC@decwrl.ARPA (B.J.)
To: telecom@bbncca.ARPA
Subject: Re: DTN
DTN (Digital Telephone Number) is Digital's internal telephone number
prefix. For our site, the internal DTN prefix is 282 but on the outside
one uses 486.
Some more information. DTNs are 7 digit numbers and the first three
are based on the site. Like the site mentioned above, the external
prefix of my site is 617-486. However, our DTN prefix is 229 rather
than 282. Furthermore, there are cases where the DTN prefix does not
uniquely specify the external prefix. This means that a DTN is not
useful to people outside of DEC.
B.J.
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Date: Wed, 15 May 85 13:28:47 cdt
From: nather%utastro.UTEXAS@ut-sally.ARPA (Ed Nather)
To: telecom@Berkeley
Subject: dumb question
A friend got a Hayes 1200B internal modem for his IBM PC, which he wants
to use to answer his office telephone at night, to permit Bulletin Board
access. The modem works OK on dialout, providing one of his 3 lines is
selected via a pushbutton on a handset also attached, but refuses to
answer the phone when it rings. The handset hooks to a wall outlet via
a "modular" plug, or to a similar plug in the back of his modem marked
"phone." A separate modular plug connects the modem to the wall outlet.
Without the handset attached (and a line selected via pushbutton) the
modem can't dial out, either.
What are we overlooking? Is there some way to designate which of the 3
available lines the modem will answer, assuming it can be made to answer
one of them?
Any help will be much appreciated.
Ed Nather
Astronony Dept, U of Texas @ Austin
{allegra,ihnp4}!{noao,ut-sally}!utastro!nather
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Date: Wed, 15 May 85 08:22:42 pdt
From: decwrl!decvax!ittvax!dcdwest!sdcsvax!sdcrdcf!RDCF.SDC.UUCP!darrelj@Berkeley (Darrel VanBuer)
To: sdcsvax!dcdwest!ittvax!decvax!decwrl!ucbvax!telecom@Berkeley
Subject: Re: TELECOM Digest V4 #191 212 modem UUUU-echo
Cc:
If you're lucky enough to have one of those old fashioned modems with a
front panel full of lights and buttons, you can get back out of this echo
state by manually turning on remote digial loopback for a few seconds, then
turning it off [the start test signal is ignored by the remote modem since
it's already in test, but the stop test signal works OK].
Darrel J. Van Buer, PhD
System Development Corp.
2500 Colorado Ave
Santa Monica, CA 90406
(213)820-4111 x5449
...{allegra,burdvax,cbosgd,hplabs,ihnp4,orstcs,sdcsvax,ucla-cs,akgua}
!sdcrdcf!darrelj
VANBUER@USC-ECL.ARPA
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Date: Mon, 6 May 85 16:33:50 EDT
From: Ron Natalie <ron@BRL.ARPA>
To: schoch@ucb-vax.ARPA
Subject: Re: Pay phone earpiece
I suspect it is for coupling to hearing aids that have a telephone
switch. You didn't need these before, since the speaker itself
had the coils.
-Ron
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Date: 17 May 85 03:00:16 EDT
From: *Hobbit* <AWalker@RUTGERS.ARPA>
Subject: Equal access idea
To: telecom@RUTGERS.ARPA
How tight is the code that keeps track of who has what carrier? I envision
folks finding bugs that allow use of a random carrier and it not being able
to find a billable account for the call it just completed.
This is probably too simplistic, of course. Although most carriers at some
point have left themselves wide open due to silly bugs, if there is a unified
''login'' protocol, things should be fairly secure. They aren't so ''upstart''
as they were in the early days, and have better people coding for them now!
_H* [not ''due'' til late '86 [aaaugh!!]]
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From: "Robert C. Lagasse" <lagasse%biomed.uucp@BRL.ARPA>
Subject: Telephone Innards
Date: 17 May 85 13:23:23 GMT
To: info-hams@SIMTEL20.ARPA
I'm sure everyone who reads this group has opened up a telephone to see
what's going on inside. No, I'm not writing about the new high-tech
single-piece electonic pulse phones, I mean the good old all-American
Western Electric black rotary dial desk phone. The kind that hard-wired to
a wall junction block (called a 42A) with three or four wires (third was
ground and fourth was lamp supply for lighted sets which used an accessory
transformer hiding somewhere in your cellar). I believe it is called a
"model 500" set or something. The guts of this phone are still used in
5-line with hold systems and also with DTMF dialing desk sets from W-E.
The large coil block riveted in the base which I believe is called the
"network" has about fifty screw terminals and has got to be one of the most
confusing pieces ever invented. In the first place, this thing is labelled
with numbers and letters most of which are meaningless unless you are an
installer. Half of the terminals are jumpered to others underneath where
you can't see and the others connect to coil windings and .......caps??
Anyway, this network thing is filled with thick sticky goop either to keep
people like myself out of it or to seal it from moisture.
The other strangeness in this phone is the number of contacts used in the
"hook switch". This switch must be a million-pole double-throw. It seems
that the only things that would be needed to be switched are the network
(completely out of circuit) and the bell with it's series cap (in circuit)
when the phone is "on-hook" and vice-versa for "off-hook". Sounds as if a
SPDT switch would do just fine or maybe a DPDT if you need contacts for a
dial lamp.
Now that all of the phone stuff is deregulated, none of this must be
top-secret anymore. Does anyone know where I can get the training manuals
that they teach the installers from? Those guys amaze me when they open up
these phones and actually figure out how do anything they want to with them.
Also, where do all of these new modular jack numbers come from (RJ-11,
RJ-35, etc.) ? Is there a committee somewhere dreaming these up and do they
relate to ANYTHING? Comments appreciated.
Bob Lagasse biomed. eng. MGH
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Date: Tue 14 May 85 14:38:49-PDT
From: HECTOR MYERSTON <MYERSTON@SRI-KL.ARPA>
Subject: Close but .....
To: telecom-request@BBNCCA.ARPA
Re Joe Yao's reply in Issue 192. This description is indeed the way things
were. Today there IS such a thing as a nation-wide 800- number. All 800-
numbers are basically psuedo numbers which are translated by the Nr 4 ESS
to actual, dialable numbers. In the past the state in which the call was
answered was excluded since, as Joe points out, this intra-state service
is under a different tariff. Today the same number can be used nationwide
although the customer gets two individual lines, one will receive inter
state, the other intra.
Next series of enhancements to 800 service lets the customer (provider)
provide for answering at different locations by time of day, traffic load
etc by DIRECTLY telling the network how to handle his calls. The start
of the Software Defined Network.
+HECTOR+
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End of TELECOM Digest
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