24 hours in the life of a (flakey) ADSL line

A signal-to-noise ratio graph from a Speed Touch Home. The 0-255 scale represents the DMT carrier number. The 0-143 scale is time in 10-minute intervals since Midnight, and the 0-50 scale is the operational channel S/N ratio in dB.

Some notes:

• Carriers 0-7 are unused (this is the voice band).
• Carriers 30-37 are unused (this is upstream/downstream guard band).
• There is significant interference on Carrier 181 (782 KHz).
• There was a significant disruption of service at about 700 minutes after midnight (just before noon), followed by very good quality across all carriers.

This data was collected by the Speed Touch Home using the "Golden" channel and downloaded using the "EXPERT" mode.