telecom@ucbvax.ARPA (07/31/85)
From: Moderator <Telecom-REQUEST@MIT-XX.ARPA>
TELECOM Digest Tuesday, July 30, 1985 7:57PM
Volume 5, Issue 12
Today's Topics:
Re: TELECOM Digest V5 #11
Private lines again...
2400 bps modems
call waiting & 3-way calls
Re: News from Pacific Bell - You can now cancel Call Waiting
Call wainting while 3-way calling in progress
re: TELECOM Digest V5 #11 - Leased Lines
Short Haul DDS
----------------------------------------------------------------------
From: kyle.wbst@Xerox.ARPA
Date: 29 Jul 85 1:18:04 EDT
Subject: Re: TELECOM Digest V5 #11
re: request for info on phone surge protectors...
------------------------
#1: ? 26-Apr-85 14:11 mike@LOGICON.ARPA Re: PHONE Surge Suppressor
Return-Path: <mike@LOGICON.ARPA>
Received: from LOGICON.ARPA by Xerox.ARPA ; 26 APR 85 14:11:19 PST
Date: 25 Apr 85 21:38 PST
From: mike <mike@LOGICON.ARPA>
To: kyle.wbst
Subject: Re: PHONE Surge Suppressors
In-Reply-To: Message from "kyle.wbst@Xerox.ARPA" on 04/25/85 at 08:11
Thanks for your information about phone surge suppressors. The catalog
address where I found this item was:
Global Computer Supplies
45 S. Service Road
Dept 52
Plainview, NY 11807 (800)8-GLOBAL -----(yeah, I really hate it when
they SPELL out
a name but don't have a phone here next
to me to decode it *sigh*)
The items in question are:
Surge Sponge (RS232 connector type protection)
Stock Number C4592
Cost = $49.00/ea
Tele-Guard (for the phone line)
Stock Number C4593
Cost = $19.00
Additional thoughts for my case is the fact that I live here in San Diego.
Nearly all the lines here are barried underground for phone and electric
service. Also, there really are NOT too many electrical storms out this
way. I have been living here for about three years and have yet to see
a serious electrical storm. It is generally just a piddling type of rain
storm. No really serious winds around this way either.
Thanks again. Hope this information helps you out.
Mike Parker
ARPA: mike@logicon
------------------------------
Date: Monday, 29 Jul 1985 06:38:40-PDT
From: goldstein%donjon.DEC@decwrl.ARPA (Fred R. Goldstein)
Subject: Private lines again...
I'd like to thank the myriad contributors to Telecom who have corrected
my geography. I used to think that Harvard Square and Tech Square were
in Cambridge, Massachusetts. (Heck, I was just there yesterday!) Now,
I'll remember to bring my passport, since I've learned they're in
California. Either that, or Pac Bell has taken over the exchange from
NET. Too bad for the fellow who wanted a 43401 line; New England Tel
seems much more cooperative than Pac Bell in that regard, and they've
got LOTS of raw copper plant between the two Cambridge COs. But I
stand outvoted: PacBell won't do it, especially in Cambridge.
Re. "how much does a private line cost" (from N1ALX) --
Let me paraphrase. "How much does one of those ham radio thingies cost?
My phone bill is very big. I called up Radio Shack and they didn't give
me a clear answer. Besides, when I asked if a radio they had could send
pictures as well as voice, they said something about morse code, whatever
that is. I've seen some walkie-talkie type radios; can they talk to
Australia? How about Russia? Do they speak English?"
There are LOTS of different types of private (leased) lines available,
depending upon distance, application, etc., etc. Alarm lines are very
different from voice or data lines, etc., and the rates are both complex
and rapidly changing. No, they don't string wires on poles anymore
(especially in California! hi) except for the last link. Please send
more details or consult your local telecom department -- that's how we
make our living.
Fred (k1io)
------------------------------
Date: Mon, 29-Jul-85 04:30:09 PDT
From: vortex!lauren@rand-unix (Lauren Weinstein)
Subject: 2400 bps modems
I posted a longer version of this elsewhere. I have gotten a number
of reports of incompatibilities with the US Robotics 2400 modem.
A major modem expert tells me that he personally would NOT buy a 2400
modem at this time unless it cost $100 or less! "Too much incompatibility
and confusion just now" was his quote. "Don't get one yet unless
you only intend to talk to sites that run the identical modem at the
identical speed. The situation is changing, but not quite yet..." he said.
Just passing this along.
--Lauren--
P.S. Watch out for those so-called 9600 bps modems. By the time
you get past error-correction, you may have a true throughput
a LOT lower than 9600. Also, most of these units are really
half-duplex, with "simulated" full-duplex--which means that
in many applications your effective throughput is even
lower than you might expect from the error correction alone.
--LW--
------------------------------
Date: Mon, 29 Jul 85 12:44:41 EDT
From: Devon S. McCullough <DEVON@MIT-MC.ARPA>
Subject: call waiting & 3-way calls
When I lived in DC I had ALL the features, and call waiting worked
fine during a 3-way call. I would often leave the other two people to
amuse each other while I got rid of the incoming call. My explanations
didn't stop my nontechnical friends from calling me a phone phreak.
------------------------------
Date: Mon, 29 Jul 85 10:41:32 PDT
From: David Alpern <ALPERN%SJRLVM4.BITNET@WISCVM.ARPA>
Subject: Re: News from Pacific Bell - You can now cancel Call Waiting
JSol: When I had both features in Brookline 6 years ago, I was able
to "cancel call-waiting" by dialing something like weather, making the
real call on 3-way, but never connecting the two parts of the call. So
I'd have to agree it's always worked that way.
Interesting note on billing between the operating companies: on a recent
trip I made two in-LATA calls with a calling card, which is ambiguously
AT&T and Pacific Bell (I have the same number from each). One, in
Illinois, came back in the AT&T section of the bill, and one in North
Carolina came back in the Pacific Bell section. Both came with state
taxes. It seems that some of the companies trade bills directly, and
some prefer to trade with AT&T.
- Dave
------------------------------
Date: Mon 29 Jul 85 12:03:14-PDT
From: Ole Jorgen Jacobsen <OLE@SRI-NIC.ARPA>
Subject: Call wainting while 3-way calling in progress
I can definately confirm that call waiting works while a three
way call is in progress. I once talked to a person in London
and one in Barbados at the same time and someone called me
locally to ask what I was doing for lunch. It worked just fine,
the two people could hear each other while I was answering the
other call. My CO is a #1A ESS (PLACA02).
Ole
------------------------------
Date: 29 Jul 85 14:22:18 PDT (Monday)
Subject: re: TELECOM Digest V5 #11 - Leased Lines
From: Cottriel.ES@Xerox.ARPA
Bob, What is the exact application for your ~leased line~?
re: "...I believe consist of nothing more than a pair of wires
from one site, to the phone company central office,
then to the other site with no switching or electronic
intervention in between...."
The key here is: "no switching or electronic intervention in between"
You can't usually get a metallic pair outside of the serving area of
the first Telco Central office. So, if you need DC continuity past
this boundary, you may as well forget it.
If on the other hand you will be sending tones in the range of ~300 to 3000hz,
then you could order 3002 facilities, which are voice grade lines suitable for
data transmission. Cost is based upon tariff mileage which may be longer or
shorter than "as the crow flies" mileage. There are also "local loop" and
"termination" charges involved, plus a one time installation fee.
There are also 1000 series facilities that are "...unconditioned channels
capable of transmitting direct current mark-space or binary signals at rates
up to 150 bauds. These channels are not suitable for the transmission of
alternating current tones; they are furnished for half-duplex or duplex
operation on a two-point or multi-point basis." [FCC Tariff 260, ISM TTGD-2]
These may or may not have DC continuity outside of the first telco office.
There are many variables involved - Call me if you want to talk about it.
John Cottriel
213-615-2095
------------------------------
Date: Mon 29 Jul 85 08:47:02-PDT
From: HECTOR MYERSTON <MYERSTON@SRI-KL.ARPA>
Subject: Short Haul DDS
> Again, in California, DDS (Digital Data Service) would be the way
>to go. The prices are more than competitive to analog, and the
>equipment is much better. You can get a CSU/DSU (channel service
>unit, data service unit) for $695.00 and it will run at 2400, 4800
>9600 & 56kb switch selectable. You pay the telco for the speed you
>wish to run, and they supply the clock. The one drawback, is the
>installation cost, about $800 per site. The mileage fee would be
>next to nothing. I would gestimate you will have a monthy fee of
>under $100 with the investment of $3000.
Per the Cal PUC tariff no 156-T, monthly recurring charges for a 2
mile 56kbps DDS between two points served by the same office are:
1. $40 "channel connection", 2. $215 "per channel" plus $ 3.90
"per mile"; for a non-trivial total of about $260/month
------------------------------
End of TELECOM Digest
*********************