kkim@uiucdcsb.UUCP (02/14/87)
The following is an excerpt from the "OFFLINE" issued by
the CSO (Computing Services Office), University of Illinois at
Urbana-Champaign, Urbana, IL (without permission).
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Modem problems with call waiting?
How to get around it
We have heard that people who have the call waiting feature on their
phones often have a problem when they use that line for computer hookup via
a modem. apparently, the beep that notifies you of an incoming call
interrupts the carrier tone long enough to cause your modem to break
the connection. This, of course, frequently results in the loss of data
or work that you have been doing. Listed below are several ways you can get
around this problem
Basically you can try three methods.
1. Cancel call waiting
In certain areas, call waiting can be canceled on a call-by-call basis.
^^^^^^^^^^^^^^^^
Before you place a call (e.g., to a computer), listen for the dial tone; then
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
a) Dial *70 from a regular push-button phone (or 1170 from a rotay dial
or a 10-button phone).
b) Listen again for the dial tone, then dial the number you wish to reach
(e.g., the computer).
Call waiting is then canceled for the duration of that call, and is
automaticallly restored when you hang up. Anyone attempting to call you will
get a busy signal.
Check with the phone company to see if your exchange has this feature.
2. Call Forwarding
If you also have call forwarding on your phone, (and somebody to whom to
forward your call), this method will work.
While your phone is on call forwarding, it will attempt to produce a
short ring to indicate a call coming through; however, this ring is handled
differently than a call waiting signal, and will not cause problems.
Remember to deactivate call forwarding when you are through.
3. Extend the Carrier-Loss Detection Time
To use this method, you must have good communications software that
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
checks the data transmission.
Most communications software packages allow you to increase the amount
of time that the carrier tone can be lost without actually breaking the
connection. If you set this value to a duration longer than the call
waiting beep, the connection should be maintained.
However, unless you are using an error-free protocol, there will be some
loss of data and the addition of extraneous noise characters in
you data because of the beep.
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Hope that it will help.
Kyongsok KIM
Department of Computer Science
University of Illinois at Urbana-Champaign
my addresses are as follows:
network address
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arpanet kkim@b.cs.uiuc.edu (domain format) OR
kkim@uiuc.arpa (alias)
csnet kkim@uiuc.csnet,
kkim%uiuc@csnet-relay.arpa (obsolete), OR
kkim%uiuc.csnet@csnet-relay.arpa (obsolete)
usenet/uucp {seismo, pur-ee, ihnp4, convex, cmcl2}!uiucdcs!kkim
* If you cannot send mail to me using one of addresses above, try another.