Zypcom Z34-PC, Руководство пользователя

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Modem Drops the
Connection
Frequent line drops are normally due to a noisy
telephone line, a low-quality modem at one end of the
connection, or a modem incompatibility between the
modems. If the line or lines are bad, the remedy is
simple. If you experience frequent connection drops,
check to make sure you have the latest code for your
Zypcom modem. Call our BBS (510-783-2580) to get a
new code to reflash your modem, if any. To see if the
line drops are due to a low-quality modem, try another
brand but use the same telephone line. If the problem
goes away when you try another brand, then call
Zypcom technical support and have them check out
your disconnect problem. If the problem does not go
away, then you might try to use your Zypcom modem at
a lower maximum line speed to make it more immune to
line drops.
Modem Fails to
Handshake
The occasional failure to handshake is normally due to
a telephone network problem. A frequent failure to
handshake is normally because the modem failed to
negotiate a carrier or an error control link. In the no-
carrier case, the modem will hang-up clearly upon
issuing a "no carrier" message. In the no-error control
case, the modems actually go on-line, but at a speed
that does not allow an error control link to be
successfully negotiated. Hence, errors occur during a
computer session login (particularly with PPP links) and
eventually cause the modems to be hung-up by the PC
software. This kind of problem is usually site specific
(that is, there are no problems with many other
numbers) and is due to some peculiarity in the modems
which are communicating. If the problem is repeatable,
try reducing the maximum line speed (S37).