dave@utcsrgv.UUCP (Dave Sherman) (10/15/84)
One of our people often does demonstrations of data communications
from places in which he can't get a jacked phone. The quality of the
line with an acoustic coupler at 1200 baud is often bad, and he's
asked me whether our direct-connect GDC modems can be used in such a case.
It occurs to me that if you take a phone jack which has a female
RJ-11 socket and four coloured wires with connectors coming out
at the other end, it might be possible to wire such a jack into
either the wall plug (to which the phone is permanently wired) or
the phone itself. Has anyone tried this? Is it likely to work?
If you did it in a hotel room, would there be any chance of
doing any harm to the switchboard?
I assume it would be possible to open up the phone, and wire
in the jack's red and green connectors where the line from the wall
comes into the phone. Then plug the modem into this "portable
jack (!)", and you're in business.
Thanks for any comments or suggestions.
Dave Sherman
The Law Society of Upper Canada
Toronto
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{ allegra cornell decvax ihnp4 linus utzoo }!utcsrgv!davefaunt@saturn.UUCP (Doug Faunt) (10/18/84)
I do this fairly regularly, since I go to SF conventions a lot and often take a terminal (I took a HP2382 to Baltimore, via Boston, on airlines). I carry a cable with spade lugs at one end, and a modular plug at the other, as well as a "T" adapter, and a cable with modular plugs at both ends, and have had no trouble in any hotel, including some pretty old and ratty places. Alligator clip leads would be a little more convenient sometimes, but since I'm usually staying for a few days, it doesn't matter much. Newer places often have modular connectors at one end or both, with the little lever cut off short, which is no problem for my trusty knife, and at least one hotel has had standard stuff, withe standard lever. I also carry an extension cord with multiple receptacles, since that is often harder to arrange. The worst place I ever had to connect was my father's house in low-country South Carolina, because they'd prewired the house with terminals only accessable from under the house, or in the instrument, and he had a fancy phone in a wooden box at the place where I could set up the terminal. I've now got an HP110, and can run it, the disc, and printer all on batteries, but I still have to plug in a 1200 baud modem, since HP has put a 300baud unit internally. Doug Faunt ...!ihnp4!hplabs!faunt faunt%hplabs@csnet-relay
jsol@bbncca.ARPA (Jon Solomon) (10/18/84)
Ma Bell supplies a modular jack that has a special clip which will clip
directly to the screw terminals in any phone outlet (especially one with no
jack). They cost around $5.00 and are cheap enough to leave the modular jack
in the place you give the demo.
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[--JSol--]
JSol@Bbncca (Internet)
{decvax, wjh12, linus}!bbncca!jsolron@brl-tgr.ARPA (Ron Natalie <ron>) (10/22/84)
I often take a GRID Compass computer with me on travel and it has a built in 1200 baud modem. I have a little box that I made up that has a modular jack with two alligator clips hanging off it. That and a small screwdriver is usually sufficient. You'll probably have to experiment on which lines to hook to. Most hotel phones are pretty cheap jobs and generally don't obey the red-green/black-yellow conventions that WE uses. Now if my 800 numbers just worked in Canada. -Ron
dbr@cybvax0.UUCP (Douglas Robinson) (10/24/84)
NOTE: The new digital phone systems will probably NOT work with your modems. We have travelling salesmen [:-)] that use Hayes modems and appropriate hardware to demonstrate our system to potential customers. Everything worked ok until one of the potential customers had a digital phone network in his office/company. No connection, no way, no how! I spoke with the president of the company who installed this network and he said that due to there being NO STANDARD for digital phone networks, there were MANY digital phone networks out there that are completely different in their treatment of the wires involved (thus no acceptable solution was available to us - I recommended that if the case came up again, to go rent a hotel room that used ATT standard and demo there). -- Doug Robinson Cybermation, Inc. 377 Putnam Avenue Cambridge, MA 02139 (USA) 617/492-8810 ...!mit-eddie \ ...!harvard >!cybvax0!dbr ...!mirror / Jobs don't kill programmers... programmers kill jobs.
ron@brl-tgr.ARPA (Ron Natalie <ron>) (10/25/84)
> I spoke with the president of the company who installed this network and > he said that due to there being NO STANDARD for digital phone networks, It is for this reason that BRL in particular and the Army in general is NOT using digital phone networks for hooking up computers, but going with separate and standardizable facilities for data communications. -Ron