Zypcom Z34-PL, User Manual

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4-9
4
1. Increase the minimum line speed you will allow for
any given connection (+MS command).
2. Have the phone company provide you with a higher
quality telephone line.
3. Use a Zypcom modem on the answer side as well.
Step Four: Error Control Retransmissions. A delay
due to standard error control retransmissions is more
difficult to determine. You cannot interrogate an S-
register directly to find out the number of packets that
have been retransmitted due to errors. Therefore, first
reduce the size of the V.42 packet (AT\A0) in order to
speed up retransmissions when they do occur. Check
to see if improvement has resulted. If not, reset the \A0
command to \A3 and reduce the line speed maximum
by one- or two-speed increments. If no improvement
has resulted, then delays are not due to
retransmissions.
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.