[net.dcom] Call Waiting and Modems

woods@hao.UUCP (Greg Woods) (08/08/83)

  I hope this is the right place to post this, I don't read either of these
groups.
  I have just purchased a terminal and modem, and I am worried about becoming
impossible to get a hold of while logged in. I don't want to pay to have a 
second line installed, because it is a rented apartment and I may be moving
soon. I was considering getting Call Waiting from the phone company, but I
need to know if 1) This will interfere with correct operation of the modem
when the wait signal comes through; and 2) Is the wait signal detectable (i.e.
does it print garbage on the screen). If anyone has any experience with this
I'd appreciate hearing about it. Please *mail* me responses and if there is
anything really interesting and/or there is enough expressed interest I'll
post a summary of responses. Thanks much.

-- 
                        GREG
 {ucbvax!hplabs | allegra!nbires | decvax!brl-bmd | harpo!seismo | menlo70}
       		        !hao!woods

wm@tekchips.UUCP (08/13/83)

I have used a terminal and a modem on a phone line that has call
waiting.  The call waiting signal always severed the connection, and
almost always put some gargage characters on the screen.  Usually the
fact that the system went away was enough to tell me that another call
was coming in, and I would pick up the phone and answer the call.
Worked very well.  Most UNIX programs handle the HUP signal in a
reasonable way, and rarely was any work lost.  The main exception to
this, interestingly enough, was older versions of news, which would
mark the current article that you were reading as having been read.
This bug has been fixed (at least it has been here, depends on which
news are you running).  If you have a little more money, you can get
call waiting and call forward, and forward your calls while you are
using the phone for a terminal.  One of the best deals we ever did was
have two phone lines.  We had the first line rotor to the second, and
had call waiting on the second line (you will have to convince your
local phone office that a residence phone can have a rotor on it, but
it can).  That way if the first line was in use for the terminal, calls
would rotor to the second, and if the second line was also in use, it
would get a call waiting beep.  Getting two lines like this also ended
up being significantly cheaper than two separate lines, for some
strange reason.  Probably if all the home hackers out there get this
installed, the phone company will get wise and change the rates :-(

				Wm Leler
				wm.Tektronix@Rand-relay

darrelj@sdcrdcf.UUCP (Darrel VanBuer) (08/14/83)

Call waiting generally by the telephone switch temporarily connecting your
line to a tone generator (and putting a 1/4 second hole in your
conversation).
For many modems, this is enough to drop carrier and cause a disconnect.
(Several years ago I had this trouble on the company phone system until I
requested that call waiting be disabled on my line).
	You are likely to find call-waiting a great annoyance unless you get
few calls.
	Darrel J. Van Buer	sdcrdcf!darrelj  VANBUER@USC-ECL.ARPA