3Com 005605-00 Manual

Contents

U SING MODEM S TATION72The “Link Diagnostics” screen displaysstatistics about your last connection. Thisscreen is most often used as an aid indiagnosing connection failures, but it also canprovide information about connection speedsand phone line conditions.• Modulation displays the speed and type ofconnection.• Carrier Frequency displays the electricalfrequency of the carrier signal.• Symbol Rate displays the speed of thetransmission.• Trellis Code, Nonlinear Encoding,Shaping, and Precoding all refer tomethods of handling high speed datatransmission.• The items followed by (dB), (-dB), (-dBm),and (msec) refer to variations in themodulation tones that actually carry theinformation.The rest of the screen contains informationabout CRC errors, Block Errors (Blers),resent data, and other data. This information isvery important if you experience problemstransmitting or receiving data or if you suspectproblems with your phone service.If you are having connection problems, godirectly to this screen to get this information. Ifyou save anything to the modem between the