Communication Status Indicators - Allied Telesis AT-1720AT User Manual

If a transceiver is installed on an AT-1720, the setting of the SQE
switch (heartbeat) is not important. Turning the SQE switch
OFF or ON will not result in degradation or failure of network
communication.

Communication Status Indicators

Table 6 shows the functions of the four status indicators located
below the RJ45 receptacle.
LED Color Label
Green
Yellow
Green LNK
Yellow COL
Table 6: AT-1720 Status Indicators
Indicates
TX Transmitting packet
RX Receiving packet
Valid receive link signal
Collision detected
Cabling
Used by
All media
All media
10BASE-T 10BASE-FL
FOIRL
All media
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