As I suggested in a previous post, ask if they have the Ambit modem available (we have our choice in WA.), I am quite pleased with mine.....
17 years ago
As I suggested in a previous post, ask if they have the Ambit modem available (we have our choice in WA.), I am quite pleased with mine.....
Anyone know if firmware version
I'm on my second Motorola SB5101 modem (Comcast rental) in two days. Both keep dropping signal every 30 - 60 minutes.
Here's the firmware from the modem's status page:
Software Version: SB5101-220.127.116.11-SCM14-NOSH Hardware Version: 1 MIB Version: II GUI Version: 1.0
I posted this on dslreports, and one reply said this version is known for locking up. I'm beginning to believe it.
Anyone else heard this?
Not here in Tacoma we don't. At least not the last time I checked.
the number below will give you a read out of the modems connection status. Get back with the numbers.
Mike, I have one... (got it at the office there on 6th)
(we have our choice in WA.), I am quite
I stand corrected then. I was just down there a couple months ago to get my Sis signed up and they didn't have them then. Same store too.
Doesn't your local Comcast store have modems?
signed up and they didn't have them
available (we have our choice in WA.), I am
"Bob H" wrote in news:u8-dnRsaSuDzQz firstname.lastname@example.org:
My Comcast store only offers the Motorola SB5101.
"BigJIm" wrote in news:z-adnSzW7700eT email@example.com:
Here's the post I put up on dslreports, on the Comcast HSI forum:
------------------------ This is my second Motorola SB5101 modem in 24 hours, and I keep loosing connection every 15 to 30 minutes. All lights stay solid green, including the online light, but only a power-cycle will get me back online. I will try to describe the problem and sequence of events as accurately as possible. If you stay with me to the end, thank you very much.
I live in San Carlos, CA, 94070. This is in the San Francisco Bay Area, about 20 miles south of San Francisco, and 20 miles north of San Jose (Silicon Valley area). I'm running Windows XP Home, SP2, always updated. No hubs or routers. No malware present.
My IP has remained unchanged for as long as I can remember, and is still the same. My current DHCP lease was obtained Wed. Dec. 14, 2005, 6:18:48 PM, the same time I placed my current modem, a new Motorola SB5101 in service, and the lease expires Sun. Dec. 18, 2005, 6:18:48 PM.
I have been using a Comcast rental RCA 245 modem for about three years. It's been running rock solid, giving me about 4mbps. As of December14th, I no longer have the RCA, but I remember this:
RCA 245 (consistently about 4mbps down, about 350kbps up) Down: 705.003mHz S/N 35.2dB Power: -7.5dBmv Up: 24mHz Power: 32dBmv
December 13th: I began having speed problems immediately after I power-cycled my RCA 245 modem to get the upgraded 6 mbps speed, the evening of December 13. I did several speed tests on my RCA, and they were all around 500kbps (yes, kbps). Pings to comcast.net, yahoo.com, etc. were about 300ms. The other stats shown above were unchanged. I called Comcast and they verified high pings, but said all other modem indicators were fine. They did verify that the config file would allow me to receive 6mbps, so they pushed me another modem config file. Still, speeds were 500kbps. After further research, Comcast said that the San Mateo County upgrade was not completed, but they could not configure me back to 4mbps. I'd have to wait until the upgrade was completed. Point to remember: I retired for the night, and when I got up, the RCA 245 was STILL connected to the internet just fine.
December 14th: I did some reading on the forums and posted my problem. Some replies said that the RCA 245 could not handle the new 6mbps, it was not DOCSIS2, and to swap it for a newer modem. One replier said their RCA 245 was capable of the higher speeds. He was from a different area of the country, so he may have had different firmware. I can only speculate. I looked at my original RCA 245 manual, and it was not specific about DOCSIS. It only said it was DOCSIS compliant, and could receive up to 7mbps (perhaps with updated firmware?). A google search found a site that (once?) distributed the RCA 245 and some press releases on it from some time in the past, which also were not definitive. The RCA 245 was on the list of Comcast's approved modems, but that list may not have been updated for the new, higher speeds. I couldn't find anything specific, so I called Comcast and they told me to go to their walk-in location and swap the RCA 245 out for a newer modem. I did that on the evening of December 14th. I was given a Motorola SB5101.
That evening, I called Comcast to register the SB5101's MAC. I was up in about five minutes. Receive, send, and online lights were solid green. Pings were around 50ms. I did a Speakeasy speed test and got 7.399 mbps/354kbps. I figured that too high on the download speed, but I'd never achieved that, and I thought that at least the new SB5101 had solved my speed problems.
Within the hour, I could not reach the internet, but all lights on the SB5101 were still solid green. I power-cycled, which re-connected me to the internet, and called Comcast. They checked my MAC and pushed me another config file. They were not aware of any problems in San Mateo County, and said the upgrade was complet.
Within the next hour, I couldn't reach the internet again, but again, all lights on the SB5101 were solid green. This time, while still offline, with all lights solid green, I tried to bring up the SB5101's home page (192.168.100.1), but it would not appear. I got the ubiquitous "The page cannot be displayed" message. The orange pc/activity light was solid, and blinked once in a while.
I power-cycled and was back online. I went to the SB5101's home page and saw this:
Downstream Frequency 705000000 Hz Signal To Noise Ratio 27.8 dB (RCA was 35.2) Power Level -5.5 dBmV (RCA was -7.5)
Upstream Channel ID 4 Frequency 24800000 Hz Power 34.0 dBmV (RCA was 32)
I called it a night, and decided I'd call Comcast about the low S/N in the morning. Perhaps this could be a clue.
December 15th (today): When I got up, my internet connection was gone again. I expected this. It probably happened within an hour after I power-cycled, above. I called Comcast about the low S/N. They verified from their end that my S/N was in their 'yellow' (low) zone, and said it could be a faulty modem out of the box, suggested I get a second one, and call them back to set it up. They also scheduled a truck roll for Saturday, December 17th, between 8 AM and noon.
In the evening, I picked up a second Motorola SB5101, called Comcast to register the MAC, etc., and I was online in about ten minutes. I told them the connection history, and they said to call back if it went down with this second modem. Within 25 minutes, I was not able to connect to the internet. I have the very same symptoms: all lights still solid green, including the online light, the orange pc/activity light is on solid, but blinks once in a while. (When I'm connected, the orange light blinks normally with activity).
I called Comcast, and they went over everything I had done from day one. They then checked their logs and told me there were two other customers having (unspecified) problems about a block or so from here. Comcast didn't know what kind of problems they were having, but suggested it may be the same. Who knows. Comcast marked on the CSR truck roll work order all that I had done, the symptoms of my connection, and that there were two other customers in the area experiencing problems. They told me to be sure that the CSR reviewed all these notes, and if he wasn't able to fix the problem, to be sure it is escalated.
Here's the information the SB5101 reports. By they way, the log file, even after power-cycling at least five times, hasn't changed since I first connected this modem to the internet on 2005-12-15, 18:28:12, about10 minutes after I obtained my current DHCP lease.
Here's the Log file: Time Priority Code Description1970-01-01 00:00:11 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 2005-12-15 18:28:12 6-Notice I401.0 TLV-11 - unrecognized OID 1970-01-01 00:01:34 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 1970-01-01 00:01:30 3-Critical D001.0 DHCP FAILED - Discover sent, no offer received 1970-01-01 00:01:21 3-Critical R002.0 No Ranging Response received - T3 time-out 1970-01-01 00:01:15 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:01:14 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:01:13 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:01:00 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:59 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:55 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:55 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:54 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:54 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:52 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:52 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:43 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:43 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:41 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:41 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:28 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:27 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:25 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:25 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing1970-01-01 00:00:17 3-Critical T002.0 SYNC Timing Synchronization failure
- Failed to acquire FEC framing1970-01-01 00:00:17 3-Critical T001.0 SYNC Timing Synchronization failure
- Failed to acquire QAM/QPSK symbol timing
Here's the Status page: Acquire Downstream Channel Done Obtain Upstream Parameters Done Upstream Ranging Done Establish IP Connection Using DHCP Done Establish Time of Day Done Transfer Operational Parameters Through TFTP Done Register Connection Done Cable Modem Status Operational Initialize Baseline Privacy Done
Here's the Signal page: Downstream Value Frequency 705000000 Hz Signal To Noise Ratio 27.3 dB Power Level -5.6 dBmV 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 Upstream Value Channel ID 4 Frequency 24800000 Hz Power 34.3 dBmV
Here's the Configuration page: Item Value Frequency Plan North American Standard/HRC/IRC Upstream Channel ID 4 Frequency (Hz) 705000000 DHCP Server Enabled Note: Resetting the cable modem to its factory default configuration will remove all stored parameters learned by the cable modem during prior initializations. The process to get back online from a factory default condition could take from 5 to 30 minutes. Please reference the cable modem User Guide for details on the power up sequence.
Here's a tracert when I'm able: C:\\>tracert
Tracing route to
Trace complete. Here's a ping when I'm able: C:\\>ping
Reply from 18.104.22.168: bytes=32 time=18ms TTL=52 Reply from 22.214.171.124: bytes=32 time=18ms TTL=52 Reply from 126.96.36.199: bytes=32 time=20ms TTL=52 Reply from 188.8.131.52: bytes=32 time=35ms TTL=52
Ping statistics for 184.108.40.206: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 18ms, Maximum = 35ms, Average = 22ms
I have been writing this note in notepad, since I can't keep my browser online for more than 30 minutes at a time. (I've lost connection 4 times in the last two hours.) I will copy and paste this to a forum window. My apologies if any formatting is lost.
Any thoughts on any of this are welcome.
Thank you very much.
----------------------- End copy of post on dslreports
I have some more information. My neighbor, two house down, has Comcast HSI. I was just there, and his connection, using a Motorola SB3100 issued to him by Comcast years ago, is running at 4mbps just fine. In my area, cable splits for TV and HSI are done in fours. A trunk line runs up our street, which splits to his house. I'm not on the same split, but the trunk then runs another 50 feet or so, and then feeds another four homes, one of which is mine.
I just did a release/renew, and where before I had a four day lease, I now have a ONE HOUR lease. My modem lost connection in 12 minutes. I power-cycled, did another release/renew, and got a four day lease. Very strange to me.
Mine actually came off the truck, I did specify the Ambit before they rolled for service....I do not believe we have a Comcast store in Spokane Wa. & that everything comes off the truck.....anyway, It was just a thought.
your power level is low it should be between 45 and 55 the other setting are within tolerance but could be better.
"Bob H" wrote in news: firstname.lastname@example.org:
Thanks, I appreciate the thought.
Bruce wrote in news:Xns972ED8F96EA39parcxmannetscapenet@220.127.116.11:
Well, I'm back up and running, at least for 5 1/2 hours now, which is much longer than the 10 minutes or so I could maintain last night, or for the last few days. Last night, my uptimes were between 2 minutes and 20 minutes.
The Comcast tech arrived this morning and was here for about 45 minutes. By the time he left, the primary parameter that improved was my S/N. It rose from about 28 to 34.
He checked signal levels at the modem, at the drop that comes into my house, and one junction downstream, across the street from me. (My neighbor is fed from this same junction, and he has been running fine. I checked with him last nght.) The Comcast tech also installed a different modem. I don't know if disconnecting and reconnecting connections in the process of testing improved my S/N, or the different modem helped. Unfortunately, there was a slight language barrier (please, I'm not complaining), so it was hard to ask questions.
At the modem, the tech read my downstream power at +20. He read the upstream at 0. He said they should be just the opposite. I thought normal was -10 to +10 down, and +30 to +35 up. I couldn't tell if he measured S/N.
Next, he tested at the drop, with down at +17, and up at 0.
Next he tested at the junction across the street, with down at +28, and up at 0. Again, he remarked that they should be in the opposite ranges. I agree with that statement. Perhaps his up was my down, and vice-versa. If so, I was in range for down, and nearly in range for up at the junction box.
We came back to the house.
Did disconnecting and reconnecting the connections, anywhere along the line during testing, improve anything? I don't know, because he didn't check when we got back to the house. I wish we would have done so.
I asked him if he'd install another modem. He installed a Comcast labeled Scientific Atlanta WebStar DPX2100, mfg. 8/03. It was used.
Name WebSTAR DPX2100 Series Cable Modem Cable Modem Serial Number 101904924 Cable Modem MAC Address 00:0a:73:68:2a:d4 Hardware Version 1.1 Software Version 2.0.1r1131-0304 Receive Power Level -6.7 dBmV Transmit Power Level 32.0 dBmV Cable Modem Status operational
Downstream Status Operational Channel ID 44 Downstream Frequency 705000000 Hz Modulation ??? Bit Rate 42884296 bps Power Level -6.8 dBmV Signal to Noise Ratio 34.3 dB
Upstream Status Operational Channel ID 4 Upstream Frequency 24800000 Hz Bit Rate 10240000 bps Power Level 32.0 dBmV
Cable Modem Status operational Cable Modem IP Address 10.150.222.129 Current Time SAT DEC 17 16:40:27 2005 Time Since Last Reset 0 days 04h:22m:59s Configuration File d11_m_dpx2100_silver_c05.cm Cable Modem Certificate Installed
(From the log; anyone know what this means?) Time Level Description SAT DEC 17 16:00:43 2005 critical Started Unicast Maintenance Ranging - No Response received - ...
I'm still up and running, but we'll see what happens over the next fews days or so.
Have you verified your signal at the modem? Type 192.168.100.1, in your Internet Browser...Motorolas have a diagnostic page, which is very easy to decipher. Select the "Signal" tab and check the following readings: Upstream (Tx), Downstream (Rx)and Sign-to-Noise (S/N). Your Rx signal is your actual signal level at teh modem...if it is below
-10 dBmv your signal is too low and will cause your modem to bake itself. Tx and SN are generally around the mid 30's.
How many splitters are between the main feed and the modem...too many (>1) will bounch your signal.
You can have multiple Direct Couplers, but not multiple splitters in your data line.
The tech checked three different points in the systems and there was not change in the Up Stream...which means the actual signal strength did not change (VERY BADDDD!!)...typical signal loss for every 100 feet of RG-6 cable is ~ 6 dBmv. You should have had a difference of at least 6 between your drop outside and your modem inside.
Your S/N went up...not good, but helps with t-shooting. There will be a difference given the AGC circuit & component caracteristics within each modem.
The tech has the ability, but may not have the knowledge to, check the actual noise on your line, even if it is resting on or too close to "Noisy" AC power cords, outlets and internal house wiring.
INGRESS tests for noise getting into the lines. EGRESS tests for signal bleeding out of the lines.
Isolate the cable and the DC side of the power supply cord to the modem from all AC power cords...check your SN levels before and after.
!?! Do you happen to have any florescent type lights in the room or house? They can induce noise in the AC lines, if the ballast is not grounded properly or bad.
There are a few other areas that can be checked...
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