53
•
Connection, but no communication
•
Connection, then disconnection for no apparent reason
•
Connection, but modem speed drops
•
Transmit speed significantly different from Receive speed
If you think you are having data line noise problems, try redialing. When you redial, the phone
company will probably route your call through a different circuit, which could result in a clearer
connection. If that doesn’t help, wait a while and try redialing again. This should solve the
problem. If not, you can also use your telecom software to set your transmission rate lower. Refer to
the “Rate Renegotiation” discussion in
High Speed Communication
for information on
setting your transmission rate.
Slow Downloads
If you download files from a BBS or online service, you should expect a theoretical CPS (character
per second) rate about 1/10th of your connection rate (i.e., 33,600 bps = 3360 cps) because it takes
about 10 bits to transmit each character.
There are many causes for slow transfer speeds. Your computer or software may not keep up. Slow
disk drives on either end can slow it down. The remote server may be slow. The Internet between the
remote server and the one you are dialing into may be slow. The server you have dialed into may be
slow. The remote system may have many users on it, which slows it down. (You may find your best
download speeds on many services are late at night when fewer users are on the service.) And some
services are notorious for slow downloads in general. A download of 600 - 800 cps on a CompuServe
14,400 bps line is a normal occurrence.
Multitasking
Multitasking computers allow you to do many different things while other operations take place in
the background. Although you don’t see them in progress, background operations can be complex
and can sometimes demand too much of your computer’s attention to allow high speed
communications. High speed transmissions are more reliable in a single-user situation with as few
applications as possible in use.
T
O
U
NINSTALL
Y
OUR
M
ODEM
You are uninstalling your modem, and want to remove the files that were installed with it.
Look at the files on the diskette that came with your modem. Write down the names of the files. Find
those files on your hard drive by beginning at the Start menu, and selecting Find. DO NOT DELETE
the file that ends with .inf.
If you did not receive a diskette with your modem, and you installed it using the CD-ROM that came
Problem:
Solution: