Have a Motorola SB6120 modem with a ~2 month old cable drop and all other line to the modem that are serviceable by myself being brand new (no splitters).
During install of the drop, tech put an attenuator on the back of the modem, removing it has no effect on the frequency of timeouts.
Without Attenuator -down
Channel ID 125 126 129 130
Frequency 837000000 Hz 843000000 Hz 861000000 Hz 867000000 Hz
Signal to Noise Ratio 38 dB 38 dB 38 dB 38 dB
Downstream Modulation QAM256 QAM256 QAM256 QAM256
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
2 dBmV 2 dBmV 2 dBmV 0 dBmV
Without Attenuator - up
Channel ID 3
Frequency 31000000 Hz
Ranging Service ID 609
Symbol Rate 5.120 Msym/sec
Power Level 36 dBmV
The values stay similar with attenuator on, only change is power levels, which go to -1 or -2 dBmV
T3 timeouts such as :
Aug 30 2012 18:16:16 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:56:39;CMTS-MAC=64:00:f1:3f:fd:7d;CM-QOS=1.1;CM-VER=3.0;
occur frequently, as often as 2 minutes or as far as a few hours apart, most often occurring after noon.
Was using the modem for 1.5 years at previous location across town without having a T3 timeout issue such as this.