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Marek Lipka Member	# Posted: 12 Jan 2010 18:38 - Edited by: Marek Lipka I know that there is another thread like this but I did not want to hijack the thread so I thought I'd make my own. I would really appreciate any help to resolve this. I have Comcast cable, phone and internet. They have provided me with a Arris Touchstone Telephony Modem (model TM602G/CT) and it keeps rebooting itself. It seems to happen when I hook up a Comcast DTA. This is how my setup is: line from the pole comes to the house and is split by a 2 way splitter; one goes upstairs to a Comcast DTA. The other goes to my basement where it is connected to an amplifier and then to a 3-way splitter. From this 3-way 1 output is connected to the modem, 1 to a Comcast HD set-top box, and the last runs another 30 or so feet to a second Comcast DTA box. Now when I hook up the output that runs to the second DTA (the one in the basement) then the modem keeps resetting. When I unhook it, it works fine. The 2 way splitter outside is a little old but is rated for 5-1000Hz and the 3way in the basement is newer but only rated 5-900Hz. Below I posted the Event Log and Status Parameters (these are without the DTA being plugged in.) RF Parameters Downstream Freq/Power: 735.000 MHz -1 dBmV Signal to Noise Ratio: 38 dB Modulation: QAM256 Upstream Freq/Power: 36.500 MHz 54 dBmV Channel Type: DOCSIS 2.0 (ATDMA) Symbol Rate: 5120 kSym/sec Modulation: QAM32 Status System Uptime: 0 days 0h:24m:51s Computers Detected: 1 CM Status: Telephony-AC Power Iso OFF Reg Complete Time and Date: TUE JAN 12 18:37:46 2010 DOCSIS(CM) Events Date Time Event ID Event Level Description *** 18000200 3 UCD invalid or channel unusable * 20000200 3 No Ranging Response received - T3 time-out * 18000200 3 UCD invalid or channel unusable * 17000100 3 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing * 20000200 3 No Ranging Response received - T3 time-out * 18000200 3 UCD invalid or channel unusable * 20000200 3 No Ranging Response received - T3 time-out 1/12/2010 18:03 20000400 3 Received Response to Broadcast Maintenance Request, but no Unicast Maintenance opportunities received - T4 timeout 1/12/2010 18:03 17000100 3 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1/12/2010 18:05 20000200 3 No Ranging Response received - T3 time-out 1/12/2010 18:06 18000200 3 UCD invalid or channel unusable 1/12/2010 18:06 20000200 3 No Ranging Response received - T3 time-out 1/12/2010 18:07 18000200 3 UCD invalid or channel unusable 1/12/2010 18:07 17000100 3 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1/12/2010 18:08 20000200 3 No Ranging Response received - T3 time-out 1/12/2010 18:08 18000200 3 UCD invalid or channel unusable 1/12/2010 18:09 20000200 3 No Ranging Response received - T3 time-out 1/12/2010 18:09 18000200 3 UCD invalid or channel unusable 1/12/2010 18:09 17000100 3 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing * 17000400 3 SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period PACKETCABLE(MTA) Events Date Time Event Level Enterprise Event ID Description MAC Address Endpoint Name 1/12/2010 18:14 5 4115 16 MTA TFTP: Successful 00:15:CF:44:52:3C *****************************/********** 1/12/2010 18:14 5 4115 26 MTA PROV: Successful! 00:15:CF:44:52:3C *****************************/********** 1/12/2010 18:14 5 4115 3 Voice Line State Change, Line Number = 1, Prev State = OOS, New State = IS 00:15:CF:44:52:3C AALN/1:*****************************/**** ** 1/12/2010 18:14 5 4115 3 Voice Line State Change, Line Number = 2, Prev State = OOS, New State = IS 00:15:CF:44:52:3C AALN/2:*****************************/**** ** 1/12/2010 18:14 5 4115 14 Power Supply Telemetry Log - TELEMETRY NORMAL 00:15:CF:44:52:3C *****************************/************
Shnerdly Moderator	# Posted: 12 Jan 2010 20:30 Welcome to the forum Marek Lipka. In a case like this, it is always better to start your own thread. It reduces confusion when trying to address two problems with two different people in the same thread. When you disconnect the DTA that seems to be causing the problem, on which end are you disconnecting it, at the DTA or at the splitter. If you are disconnecting it at the splitter, it may be a bad coax. It is always best to have no more then one splitter in the line ahead of the modem. You said you have two splitters and an amplifier. Often times signal amplifiers have a negative affect on cable data transmissions which is what you need for your internet. Have you tried eliminating the amplifier? I suspect the amplifier is the problem. Try eliminating it or adding a two way splitter that goes to the amp and the modem and then split again after the amp for the DTA and HD Box. Don't use the three way splitter though unless you terminate the open connection. I think Radio Shack sells the terminators, if not, I know they sell the splitters.
Marek Lipka Member	# Posted: 12 Jan 2010 21:12 - Edited by: Marek Lipka Thanks for the quick response. To clarify, the problem occurs when the DTA is hooked up. I disconnected it at the 3 way splitter. Before today, everything was hooked up the same (amp, splitters...etc) as it is now with the exception of the second DTA in the basement (coming off the 3 way splitter). Previously that cable was just hooked into the television without any set-top box or DTA. The problem seems to have started when I installed the DTA. Do you think there is something I can do to solve the issue myself, without having a tech come out ? Also something I noticed is that the downstream power tends to go high. When the modem is restarted it starts out around -9 db or so and then after some time when I checked it, it was at +10 db. PS some of the wiring is old, for example the one running from the 3 way splitter to the 2nd DTA. Update: I disconnected the troublesome cable at the splitter and disconnected it at the DTA to test it out, doesn't seem to make a difference. Also if I'm getting shocked when I touch the splitter and the end of one of the coax cables(not connected), that's bad right...?
Marek Lipka Member	# Posted: 12 Jan 2010 22:10 Update 2. I did what you recommended, hooked up a splitter before the amp and then another 2 way after to go to the HD box and the DTA. So far so good, 30 minutes up time without an issue, while playing MW2 Online and Streaming a basketball game on the PC. Hopefully this solution will keep working. Thank you for your help so far, and hopefully I won't be needing anymore. I'll update you again tomorrow or so. Thanks again.
Marek Lipka Member	# Posted: 13 Jan 2010 17:22 Okay, 20 hours uptime so I think you solved my problem. Thank you for your help.
Shnerdly Moderator	# Posted: 13 Jan 2010 19:09 I'm glade we were able to help.

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