JAJZ801@CALSTATE.BITNET (Jeff Sicherman,CSU Long Beach) (05/09/89)
I know this question involves ANCIENT equipment but I need an answer
involving no hardware replacement (of modem or phone), extra hardware
is OK.
Specifically, we have a 1200 baud, Racal-Vadic VA 3451 modem and a
multiline, button controlled, 1A2-type phone system. The modem is used
infrequently and shares one of the voice lines. (It is kept in manual
answer mode.) When it is in use, we would like it to light the button
on the phone system for that line - which it currently does not do, so
people occasionally interrupt the modem call and file transfers.
As a last resort, if there are EXTERNAL modems that will do the job,
we might consider replacement. Internal modems are OUT (modem is shared).
Switching the phone system is definitely not possible at this time. What
I am really looking (probably wishing) for though, is a Radio-Shack type
gatchit to do this (fruitlessly, probably).
jeff Sichermanleonard@bucket.UUCP (Leonard Erickson) (05/10/89)
In article <8905090741.AA18208@ucbvax.Berkeley.EDU> JAJZ801@CALSTATE.BITNET (Jeff Sicherman,CSU Long Beach) writes:
<
< I know this question involves ANCIENT equipment but I need an answer
<involving no hardware replacement (of modem or phone), extra hardware
<is OK.
<
< Specifically, we have a 1200 baud, Racal-Vadic VA 3451 modem and a
<multiline, button controlled, 1A2-type phone system. The modem is used
<infrequently and shares one of the voice lines. (It is kept in manual
<answer mode.) When it is in use, we would like it to light the button
<on the phone system for that line - which it currently does not do, so
<people occasionally interrupt the modem call and file transfers.
<
< As a last resort, if there are EXTERNAL modems that will do the job,
<we might consider replacement. Internal modems are OUT (modem is shared).
<Switching the phone system is definitely not possible at this time. What
<I am really looking (probably wishing) for though, is a Radio-Shack type
<gatchit to do this (fruitlessly, probably).
*Most* external modems will do this .... (and this means that you get
loads of fun when you plug one into an RJ-14 jack :-( )
As for a gadget to do what you want with the existing modem, on page
88 of the current Radio Shack catalog, we have a "four line tap"
(cat no. 43-270) and a "single line tap" (cat no. 43-271). Just
hook one of these up to a standard 25-line connector and it should
do what you want. For only $15 or $20...
--
Leonard Erickson ...!tektronix!reed!percival!bucket!leonard
CIS: [70465,203]
"I'm all in favor of keeping dangerous weapons out of the hands of fools.
Let's start with typewriters." -- Solomon Shortcy@pnet51.cts.com (Cyril Bauer) (05/10/89)
I'll look around and see what I can come up with. I don't think it'll be all
that hard. All that is needed is some way to short the a&a1 leads when the
modem is on the line. How about an extra switch on the side?? That's all that
would be needed.
/s
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INET: cy@pnet51.cts.comhenry@utzoo.uucp (Henry Spencer) (05/10/89)
In article <8905090741.AA18208@ucbvax.Berkeley.EDU> JAJZ801@CALSTATE.BITNET (Jeff Sicherman,CSU Long Beach) writes: >... When it is in use, we would like it to light the button >on the phone system for that line - which it currently does not do, so >people occasionally interrupt the modem call and file transfers. Well, this is kind of the rich man's solution, but if you switch to Trailblazers, in PEP mode you can pick up the phone all you like and the Trailblazers will ignore you. Dial the phone, sing into it, shout into it... the most that will happen is that the modems will sort of mutter to themselves "sure is a lot of noise on this line". You practically have to cut the wire to make a Trailblazer break a connection. -- Mars in 1980s: USSR, 2 tries, | Henry Spencer at U of Toronto Zoology 2 failures; USA, 0 tries. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
morris@jade.jpl.nasa.gov (Mike Morris) (05/11/89)
Jeff Sicherman,CSU Long Beach writes: > > I know this question involves ANCIENT equipment but I need an answer >involving no hardware replacement (of modem or phone), extra hardware >is OK. > > Specifically, we have a 1200 baud, Racal-Vadic VA 3451 modem and a >multiline, button controlled, 1A2-type phone system. The modem is used >infrequently and shares one of the voice lines. (It is kept in manual >answer mode.) When it is in use, we would like it to light the button >on the phone system for that line - which it currently does not do, so >people occasionally interrupt the modem call and file transfers. > > As a last resort, if there are EXTERNAL modems that will do the job, >we might consider replacement. Internal modems are OUT (modem is shared). >Switching the phone system is definitely not possible at this time. What >I am really looking (probably wishing) for though, is a Radio-Shack type >gatchit to do this (fruitlessly, probably). > > jeff Sicherman What you need is a Radio Shack 43-117. It is no longer in the catalog, but _might_ be available if special ordered. It is essentially a sensitive relay that is connected in series with the modem, bypassed with a capacitor (for AC). Physically it consists of a small box with a RJ-11 jack in one end, and a short modular male-ended cord coming out of the other end. You simply plug the cord from the modem into this device, and the device into the phone system. Each line on your phone uses 3 pairs - first is the audio circuit, second is "activity" signaling (shorted for off hook), and the third is the lamp volatge. This device simply provides a short for the second pair when the first pair is in use (by the modem). PS - If you find any, let me know! I need 3 or 4 myself. I'll be happy to draw up any connections you need - just describe what you need in mail. US Snail: Mike Morris UUCP: Morris@Jade.JPL.NASA.gov P.O. Box 1130 Also: WA6ILQ Arcadia, Ca. 91006-1130 #Include disclaimer.standard | The opinions above probably do not even
cy@pnet51.cts.com (Cyril Bauer) (05/12/89)
I left a message before about just shorting out the a&a1 leads. As someone
else pointed out it out be the next set of leads.
Anyway did you find the solution that you were looking for?
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INET: cy@pnet51.cts.comchaney@ms.uky.edu (Daniel Chaney) (05/24/89)
In article <1242@jato.Jpl.Nasa.Gov> morris@jade.Jpl.Nasa.Gov (Mike Morris) writes: >Jeff Sicherman,CSU Long Beach writes: >> >> >> Specifically, we have a 1200 baud, Racal-Vadic VA 3451 modem and a >>multiline, button controlled, 1A2-type phone system. The modem is used >>infrequently and shares one of the voice lines. (It is kept in manual >>answer mode.) When it is in use, we would like it to light the button >>on the phone system for that line - which it currently does not do, so >>people occasionally interrupt the modem call and file transfers. An alternative solution is offered from DAK, as I recall. They have a modular phone plug that will prevent those accidental pickups by disabling the other phones on that line. I am not familar with your multiline system but I have installed such a device on a multiline system before and it worked fine. Note : I did have to place this plug on the specific line (read: not the specific phone as it killed the intercom from that phone on down) DAK sells these at something like 9.95 each. -- Disclaimer : I do not work for DAK not have any interest other than some of their toys are downright fun, if not handy. -- Daniel Chaney Mail guy, archiver or Accidental Student..you decide. {uunet and the like}!ukma!chaney chaney@ms.uky.edu chaney@ukma.BITNET "No! nonono....This is Unix, you take out all the vowels!" - The Uhmmer