telecom@ucbvax.ARPA (08/10/85)
From: Moderator <Telecom-REQUEST@MIT-XX.ARPA>
TELECOM Digest Friday, August 9, 1985 4:49PM
Volume 5, Issue 15
Today's Topics:
800 numbers; 10xxx prefixes
Re: CCITT modems
Telebit Corp.
Touchtone => pulse phone gadget needed
Where can I get a Picturephone?
Re: Where can I get a Picturephone?
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Date: Mon 5 Aug 85 23:16:46-EDT
From: S.PAE@MIT-EECS
Subject: 800 numbers; 10xxx prefixes
Is MCI providing 800 service now? How do the local calling offices know
which carrier to switch an 800 call to? Is AT&T listing MCI 800 numbers?
By what mechanism does AT&T bill MCI for this?
Does someone have a comprehensive list of 10xxx numbers? I've heard of
a small long-distance company in Philadelphia. Would their 10xxx number
be re-used in other parts of the country, or do they exclusively own
their 10xxx number? The latter would seemingly imply a limit of 1000
long-distance carriers. Are there combinatorial reasons why we would never
have more than 1000 carriers, or is this just an arbitrary limit?
Using (700) 555-4141 to determine your default long-distance carrier seems
to be a big win. However, I've seen little publicity for the number. Is
this the case all over the country, or is NET just biting the bag here?
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Date: Mon, 5 Aug 85 23:24:24 pdt
From: decwrl!sun!calma!helge@Berkeley (Helge Skrivervik)
Subject: Re: CCITT modems
I have no detailed technical knowledge about the differences between
212A and CCITT signaling standards, but quite a bit of experience in
using both types:
- the 300 baud standards are totally incompatible
- a 212A modem in originalt mode can talk to a CCITT modem in answer
mode
- the opposite is NOT true
some modems commonly available can be switched to CCITT mode, a good
example is the Hayes 1200B card modem. I have not tried this in europe
though. Ventel has a new 2400 baud modem in the works that have both modes,
I have a couple on order and will check them out as soon as they arrive.
Dialing from the US to europe usually works excellent since the
connection is (almost) alway via sattelite. Dialing the other way
is (almost) always impossible because a noisy cable route is usually selected.
Dialing from the US to Austrailia aslo usually works fine, but I have
no information as to what standards they are using down under...
--helge
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Date: Wed, 7 Aug 85 22:24:13 EDT
From: mgrant@gyre.ARPA (Michael Grant)
Subject: Telebit Corp.
I finally got a hold of them. They claimed that their 800 number wasn't
working properly until yesterday. They are sending me info and pricing.
Over the phone I found out:
1) there are 2 versions of their fastlink modem:
a) a plug-in card for the IBM-PC which comes with X-Talk Fast for $1995.
b) a standalone Hayes compatable serial version for $2395.
(X-Talk Fast for an extra $150)
2) They do infact run over an unconditioned normal everyday phone line
3) Speeds upto, and possible even greater than (but not by much)
10,000 baud!
4) They use adaptive duplexing. This means that the bandwidth is shared
between the sides of the line. i.e. there can be instances when
the baud going from your terminal to the host is 200, and 9600 comming
back.
I have a feeling that soon, a modem will come along that will do real
full duplex at well over 50K baud over a phone line. Is there anyway
to find the upward limit of these things? I have been told many times
that 9600 baud was imposible over a phone line, and that it had been
PROVED imposible. How do you prove stuff like this, there are sooo
many different ways to encodeand compact things!
-Mike
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Date: Thu 8 Aug 85 15:33:25-EDT
From: Ralph W. Hyre Jr. <Ralph.Hyre@CMU-CS-C.ARPA>
Subject: Touchtone => pulse phone gadget needed
I'm looking for a box (something like a Demon Dialer*) that will convert
TouchTones* to pulses, so that my Tone phones will work on a Rotary exchange.
Bonus points will be awarded if the box provides speed-dialing and other
nifty capabilities.
For those without knowledge of demon dialers, here's what the system would
look like.
| +--- Rotary Phone
(telco) | | +-----------+
----------|-+--+ Magic Box +-- Touch-Tone phone(s)
| +-----------+
(wall)
I need this box because in Pittsburgh (unlike Boston), if you don't pay extra
for Tone service, you don't get it. (ESS does NOT default to tone here.) On
the other hand, trunk hunting is free if you have two lines of any kind, and
you can have measured and unmeasured service in the same residence.
* Who cares if Demon Dialer and Touch Tone are the respective trademarks
of Zoom Telephonics and AT&T, is your phone service the better for it?
- Ralph Hyre
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From: Jim Rees <rees%apollo.uucp@BRL.ARPA>
Subject: Where can I get a Picturephone?
Date: 5 Aug 85 18:54:24 GMT
Any idea where I can find a working or restoreable pair of Western Electric
Picturephones? I'm looking for the real thing, not a work-alike. They are
all phone company property, I know, but regular phones have leaked out, so
why not picturephones?
All suggestions, including pointers to a more suitable newsgroup (I posted
here because hams are so resourceful) are welcome.
n7ahz
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From: Larry Lippman <larry%kitty.uucp@BRL.ARPA>
Subject: Re: Where can I get a Picturephone?
Date: 7 Aug 85 13:29:38 GMT
> Any idea where I can find a working or restoreable pair of Western Electric
> Picturephones? I'm looking for the real thing, not a work-alike. They are
> all phone company property, I know, but regular phones have leaked out, so
> why not picturephones?
I too would love to tinker with some Picturephones (tm), but alas,
I think they are AT&T's best kept secret - perhaps to hide what was a rather
bad marketing blunder. I understand that there are *large* quantities of
unused Picturephones along with anciliary apparatus like Picturephone line
repeaters, special KTU equipment, etc. which are still squirreled away by
AT&T Technologies and the [former] Bell System operating companies.
Since the Picturephone was introduced ~1965, the electronic technology
used in the apparatus is quite outdated by today's standards; the Bell System
never sold enough systems to justify any newer design. If my data is correct,
the Picturephone apparatus used *all* discrete components! As far as I have
been able to observe, the Picturephone "Tele-conferencing Service" which is
still offered by some of the [former] Bell System operating companies uses no
apparatus in common with the original Picturephone station concept.
I would be interested in obtaining some Picturephones to play with
if someone knows of a legitimate source.
Larry Lippman
Recognition Research Corp.
Clarence, New York
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End of TELECOM Digest
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