Community Forum

Downstream power levels

Matthewwebster5
Contributor

Downstream power levels

Are these power levels within range? My downstream levels on some of my channels are ranging from 10.5 to 12. I'm experiencing t3 timeouts and reboots.
EG
Expert

Re: Downstream power levels

That's high to being out of spec. What do the upstream power levels look like ?



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Matthewwebster5
Contributor

Re: Downstream power levels

my upstream has 5 channels locked and range from 41 to 45.3. my number 5 channel is at 1280 ksym/sec and mother 4 are at 5120 ksym/sec

NoNoBadPuppy
Contributor

Re: Downstream power levels

Copied from another thread; these are the numbers for Comcast.  You may read other sources that cite different numbers, but these are the specs for Comcast:

 

Comcast modem level specs

Begin Quote----------------------------------------------------------------------------

These are the Comcast system / cable plant spec from the troubleshooting tips sticky topic at the top of this board. Again, they are the only ones that really matter;

 

Downstream Power Levels: -8dBmV to  +10dBmV

Downstream Signal to Noise Ratio (SNR):  >35dB 

Upstream Power Level:  +25dBmV to +54dBmV

Upstream Signal to Noise Ratio (uSNR): >31dB  

Upstream Receive Power: -2dBmV to +2dBmV

End Quote-----------------------------------------------------------------------------------------

 

EG
Expert

Re: Downstream power levels

Those aren't current. These are;

 

 

Specification      Min             Max

Downstream Power Level  
Cable Modems-10dBmV+10dBmV
Gateways and EMTAs-7dBmV+7dBmV
Downstream Signal to Noise Ratio35dB-
Upstream Power Level+35dBmV+50dBmV
Upstream Signal to Noise Ratio31dB-
Upstream Receive Power-2dBmV+2dBmV

 



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EG
Expert

Re: Downstream power levels


@Matthewwebster5 wrote:

my upstream has 5 channels locked and range from 41 to 45.3. my number 5 channel is at 1280 ksym/sec and mother 4 are at 5120 ksym/sec


They're o/k. 



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Matthewwebster5
Contributor

Internet plan

I just recently upgraded to the extreme pro 600mbps plan. On the website the plan shows up correctly, while in the my account app it still shows my plan as being the 200mbps plan. When I speed test I only get 200-250mbps and not the 600
Matthewwebster5
Contributor

Re: Downstream power levels

These are ok for a docsis 3.0 modem? My power levels are fluctuating so much now. I just upgraded from 200mbps to 600mbps and I’m not getting the new speed. I’m using a netgear c7000v2 gateway.
Matthewwebster5
Contributor

Re: Downstream power levels

i spoke to tech support today and they are sending a tech to check the lines. i am getting a lot of t3 timeout errors and fluctuating signal levels that could verify on their end. i already had the drop replaced about 2-3 months ago because it literally melted inside the box on the side of the box from the pole. 

Matthewwebster5
Contributor

Re: Downstream power levels

Matthewwebster5
Contributor

Re: Internet plan

https://imgur.com/WlsxVId

 

https://imgur.com/J7imhVD

 

as you can see by the linked screenshots it shows im still on the 200mbps plan and not the 600mbps plan. i have a tech coming tomorrow to look at lines so i hope it gets fixed.

EG
Expert

Re: Downstream power levels

The downstream power is still high. Not certain that is the root cause of the problem but you can try inserting a minus 6dB attenuator pad into the coax line at the back of the modem to balance out those power levels and see;

 

https://www.amazon.com/6db-Attenuator-Pad-1-each/dp/B0013L48XA

 

Good luck !

 

 



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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Matthewwebster5
Contributor

Re: Downstream power levels

a tech is coming out today to hopefully fix the issue.

EG
Expert

Re: Downstream power levels

Please post back with how things turn out.



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Matthewwebster5
Contributor

Re: Downstream power levels

tech came out and he said everything looked fine on his end. speed tested via ethernet and got 500mbps which is close to the speeds im paying for, but on my wifi i only get 200mbps. they immediately blamed my gateway after doing a line test and signal test and said everything looks good. i have another company moving in called metronet, i think when i can im just going to switch as im tired of having techs come out and tell me everything is good and blaming my equipment. the gateway is less than a year old. i bought it last year at tax time. he reactivated modem and made sure correct speed provisioning and boot file were loaded as well. he got 700mbps via his tester hooked to ethernet port.

Matthewwebster5
Contributor

Re: Downstream power levels

 
 
Apply               Cancel     
Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
 
Startup Procedure
ProcedureStatusComment
Acquire Downstream Channel405000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
SecurityEnabledBPI+
IP Provisioning ModeHonor MDDhonorMdd(4)
 
Downstream Bonded Channels
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25642405000000 Hz8.2 dBmV38.7 dB00
2LockedQAM25643411000000 Hz8 dBmV38.1 dB00
3LockedQAM25644417000000 Hz8.3 dBmV38.6 dB00
4LockedQAM25645423000000 Hz8.3 dBmV38.7 dB00
5LockedQAM25638429000000 Hz8.4 dBmV38.8 dB00
6LockedQAM25639435000000 Hz8.5 dBmV38.7 dB00
7LockedQAM25640441000000 Hz8.4 dBmV38.5 dB00
8LockedQAM25641453000000 Hz9 dBmV39.2 dB00
9LockedQAM25625459000000 Hz8.9 dBmV39 dB00
10LockedQAM25630465000000 Hz8.9 dBmV38.8 dB00
11LockedQAM25631471000000 Hz9.2 dBmV39 dB00
12LockedQAM25632477000000 Hz9.4 dBmV39.4 dB00
13LockedQAM2561483000000 Hz9.1 dBmV39.3 dB00
14LockedQAM2562489000000 Hz9.5 dBmV39.5 dB00
15LockedQAM2563495000000 Hz9.3 dBmV39.3 dB00
16LockedQAM2564501000000 Hz9.1 dBmV39.2 dB00
17LockedQAM2565507000000 Hz8.4 dBmV38.6 dB00
18LockedQAM2566513000000 Hz8.4 dBmV38.6 dB00
19LockedQAM2567519000000 Hz8.5 dBmV39 dB00
20LockedQAM2568525000000 Hz8.4 dBmV38.6 dB00
21LockedQAM2569531000000 Hz8.8 dBmV39 dB00
22LockedQAM25610537000000 Hz8.6 dBmV39 dB00
23LockedQAM25611543000000 Hz9.2 dBmV39.4 dB00
24LockedQAM25612549000000 Hz9.1 dBmV39.4 dB00
 
Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA91280 Ksym/sec39600000 Hz45.3 dBmV
2LockedATDMA15120 Ksym/sec35600000 Hz43.8 dBmV
3LockedATDMA25120 Ksym/sec29200000 Hz42.8 dBmV
4LockedATDMA35120 Ksym/sec22800000 Hz42 dBmV
5LockedATDMA45120 Ksym/sec16400000 Hz41.3 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
 
Extended Upstream Transmit Power
Enable Extended Upstream Transmit Power
 
Current System Time:Mon Jan 25 04:41:58 2021
System Up Time:00:12:59

 

i even just factory reset my gateway. 
 
event log:
TimePriorityDescription
2021-1-25, 04:32:23Notice (6)WiFi Interface [wl0] set to Channel 6 (Side-Band Channel:N/A) - Reason:INTERFERENCE
1970-1-1, 00:00:49Notice (6)Honoring MDD; IP provisioning mode = IPv6
1970-1-1, 00:00:44Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:41Notice (6)WiFi Interface [wl1] set to Channel 153 (Side-Band Channel:N/A) - Reason:INIT
1970-1-1, 00:00:41Notice (6)WiFi Interface [wl0] set to Channel 11 (Side-Band Channel:N/A) - Reason:INIT
1970-1-1, 00:00:38Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:27:10Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:27:04Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:26:47Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:26:45Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:02:07Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:02:00Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:43Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:26Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:24Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:14Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:13Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:02Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:01Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:53Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:52Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:41Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:39Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
ComcastChe
Official Employee

Re: Downstream power levels

Hi @Matthewwebster5. Sorry, you're still having issues after the tech visit. We can take another look at the node/lines to see if we can identify any other causes. We can also test with a leased modem to rule out any other possible issues with your modem. Where did you purchase your modem from?

 

I was hoping you could send me a private message with your full name and the numbers associated with your service address as it appears on your billing statement. To send a message, click on my name, "ComcastChe," then click send a message.


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!
Matthewwebster5
Contributor

Re: Downstream power levels

i purchased it last year from either target or best buy. its working ok for now. the tech that replaced the line 2-3 months ago put a splitter from the block and hooked it to the -3.5 line and the splitter has a -7 connection on it. another tech came behind the other one and determined nothing wrong as well. i get the full speed while wired but get barely over 200 on wifi. so for now its working for me. i will probably change out the gateway for a seperate modem and router setup so if one fails i only have to replace one item and not spend so much.

Matthewwebster5
Contributor

Re: Downstream power levels

the modem just rebooted itself, so i decided to check power levels.

ive also attached log.

 

 
 
 
 
TimePriorityDescription
1970-1-1, 00:00:46Notice (6)Honoring MDD; IP provisioning mode = IPv6
1970-1-1, 00:00:42Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:40Notice (6)WiFi Interface [wl1] set to Channel 48 (Side-Band Channel:N/A) - Reason:INIT
1970-1-1, 00:00:40Notice (6)WiFi Interface [wl0] set to Channel 10 (Side-Band Channel:N/A) - Reason:INIT
1970-1-1, 00:00:37Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:45Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:39Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-2-5, 07:01:23Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.1;CM-VER=3.0;
1970-1-1, 00:00:45Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:39Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:44Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:37Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:44Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:39Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-29, 15:18:45Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.1;CM-VER=3.0;
1970-1-1, 00:00:43Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:37Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:44Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:38Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:27:10Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:27:04Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:26:47Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-1-25, 04:26:45Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:02:07Critical (3)No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:01:5c:7e:d2:5b;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:02:00Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:43Critical (3)No UCDs Received - Timeout;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:26Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:24Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:14Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:13Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:02Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:01:01Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:53Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:52Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:41Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:39Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=38:94:ed:d9:94:d8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;

 

 
 
Apply               Cancel     
Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
 

Startup Procedure

ProcedureStatusComment
Acquire Downstream Channel531000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
SecurityEnabledBPI+
IP Provisioning ModeHonor MDDhonorMdd(4)
 

Downstream Bonded Channels

ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM2569531000000 Hz11.2 dBmV39.8 dB00
2LockedQAM25642405000000 Hz10.1 dBmV39.3 dB00
3LockedQAM25643411000000 Hz9.9 dBmV39.1 dB00
4LockedQAM25644417000000 Hz10.2 dBmV39.4 dB00
5LockedQAM25645423000000 Hz10.2 dBmV39.4 dB00
6LockedQAM25638429000000 Hz10.2 dBmV39.4 dB00
7LockedQAM25639435000000 Hz10.2 dBmV39.3 dB00
8LockedQAM25640441000000 Hz10.2 dBmV39.2 dB00
9LockedQAM25641453000000 Hz10.6 dBmV39.6 dB00
10LockedQAM25625459000000 Hz10.4 dBmV39.4 dB00
11LockedQAM25630465000000 Hz10.3 dBmV39.2 dB00
12LockedQAM25631471000000 Hz10.6 dBmV39.4 dB00
13LockedQAM25632477000000 Hz10.7 dBmV39.6 dB00
14LockedQAM2561483000000 Hz10.4 dBmV39.6 dB00
15LockedQAM2562489000000 Hz10.8 dBmV39.7 dB00
16LockedQAM2563495000000 Hz10.6 dBmV39.6 dB00
17LockedQAM2564501000000 Hz9.4 dBmV38.7 dB00
18LockedQAM2565507000000 Hz9.8 dBmV38.8 dB00
19LockedQAM2566513000000 Hz9.8 dBmV39 dB00
20LockedQAM2567519000000 Hz9.9 dBmV39.3 dB00
21LockedQAM2568525000000 Hz9.8 dBmV39 dB00
22LockedQAM25610537000000 Hz9.9 dBmV39 dB00
23LockedQAM25611543000000 Hz10.5 dBmV39.6 dB00
24LockedQAM25612549000000 Hz10.4 dBmV39.5 dB00
 

Upstream Bonded Channels

ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA45120 Ksym/sec16400000 Hz40.5 dBmV
2LockedATDMA15120 Ksym/sec35600000 Hz42.8 dBmV
3LockedATDMA25120 Ksym/sec29200000 Hz42 dBmV
4LockedATDMA35120 Ksym/sec22800000 Hz41.3 dBmV
5LockedATDMA91280 Ksym/sec39600000 Hz44 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
 

Extended Upstream Transmit PowerEnable Extended Upstream Transmit Power

 

Current System Time:Mon Feb 08 04:12:33 2021

System Up Time:00:10:43

ComcastRob
Official Employee

Re: Downstream power levels

@Matthewwebster5

Hi there! I truly apologize for the delay, I'd be glad to ensure that this gets looked into further. Please click on my handle (ComcastRob) and send a private message with your name, the complete service address (including city, state, ZIP, suite number, etc), and the phone or account number, and any pertinent details-- like the ticket number(s)-- so we can help. 


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!
Matthewwebster5
Contributor

Re: Downstream power levels

This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 531000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 9 531000000 Hz 10.8 dBmV 39.6 dB 61 0
2 Locked QAM256 10 537000000 Hz 10.6 dBmV 39.4 dB 142 0
3 Locked QAM256 11 543000000 Hz 11.2 dBmV 39.8 dB 77 0
4 Locked QAM256 12 549000000 Hz 11.1 dBmV 39.7 dB 131 0
5 Locked QAM256 13 555000000 Hz 10.9 dBmV 39.7 dB 212 0
6 Locked QAM256 14 561000000 Hz 10.9 dBmV 39.1 dB 299 0
7 Locked QAM256 15 567000000 Hz 10.6 dBmV 39.5 dB 438 0
8 Locked QAM256 16 573000000 Hz 10.7 dBmV 39.6 dB 401 0
9 Locked QAM256 17 579000000 Hz 10.8 dBmV 39.6 dB 440 0
10 Locked QAM256 18 585000000 Hz 10.6 dBmV 39.4 dB 613 0
11 Locked QAM256 19 591000000 Hz 10.4 dBmV 39.3 dB 930 0
12 Locked QAM256 20 597000000 Hz 10.7 dBmV 39.4 dB 649 0
13 Locked QAM256 21 603000000 Hz 10.7 dBmV 39.4 dB 660 0
14 Locked QAM256 22 609000000 Hz 10.8 dBmV 39.5 dB 795 0
15 Locked QAM256 23 615000000 Hz 10.7 dBmV 39.3 dB 1042 0
16 Locked QAM256 24 621000000 Hz 11.1 dBmV 39.5 dB 1078 0
17 Locked QAM256 26 627000000 Hz 10.3 dBmV 39.8 dB 0 0
18 Locked QAM256 27 633000000 Hz 10 dBmV 39.6 dB 0 0
19 Locked QAM256 28 639000000 Hz 10.6 dBmV 39.9 dB 0 0
20 Locked QAM256 29 645000000 Hz 10.3 dBmV 39.8 dB 0 0
21 Locked QAM256 33 651000000 Hz 11.2 dBmV 40.3 dB 0 0
22 Locked QAM256 34 657000000 Hz 11.2 dBmV 40.4 dB 0 0
23 Locked QAM256 35 663000000 Hz 11.1 dBmV 40.4 dB 0 0
24 Locked QAM256 36 669000000 Hz 11.6 dBmV 40.3 dB 0 0

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 35600000 Hz 43.8 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 29200000 Hz 42.8 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 22800000 Hz 42 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 16400000 Hz 41.5 dBmV
5 Locked ATDMA 9 1280 Ksym/sec 39600000 Hz 45.3 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
These are the levels right now
Matthewwebster5
Contributor

Re: Downstream power levels

so i just changed the cord on the splitter out at box. it was hooked into -3.5dbmv for the modem so i moved the line to the -7dbmv on the splitter. these are my new signal levels which are much much better.

Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
 

Startup Procedure

ProcedureStatusComment
Acquire Downstream Channel531000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
SecurityEnabledBPI+
IP Provisioning ModeHonor MDDhonorMdd(4)
 

Downstream Bonded Channels

ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM2569531000000 Hz6.9 dBmV39.8 dB00
2LockedQAM25642405000000 Hz4.6 dBmV39 dB00
3LockedQAM25643411000000 Hz4.4 dBmV38.7 dB00
4LockedQAM25644417000000 Hz4.6 dBmV38.9 dB00
5LockedQAM25645423000000 Hz4.5 dBmV38.8 dB00
6LockedQAM25638429000000 Hz4.5 dBmV38.7 dB00
7LockedQAM25639435000000 Hz4.5 dBmV38.6 dB00
8LockedQAM25640441000000 Hz4.3 dBmV38.5 dB00
9LockedQAM25641453000000 Hz5 dBmV39.1 dB00
10LockedQAM25625459000000 Hz5.1 dBmV39.1 dB00
11LockedQAM25630465000000 Hz5.2 dBmV39.1 dB00
12LockedQAM25631471000000 Hz5.6 dBmV39.4 dB00
13LockedQAM25632477000000 Hz5.9 dBmV39.7 dB00
14LockedQAM2561483000000 Hz5.8 dBmV39.7 dB00
15LockedQAM2562489000000 Hz6.2 dBmV39.8 dB00
16LockedQAM2563495000000 Hz6.1 dBmV39.7 dB00
17LockedQAM2564501000000 Hz4.9 dBmV39.5 dB00
18LockedQAM2565507000000 Hz5.3 dBmV39.4 dB00
19LockedQAM2566513000000 Hz5.3 dBmV39.4 dB00
20LockedQAM2567519000000 Hz5.6 dBmV39.8 dB00
21LockedQAM2568525000000 Hz5.4 dBmV39.4 dB00
22LockedQAM25610537000000 Hz5.6 dBmV39.9 dB00
23LockedQAM25611543000000 Hz6.2 dBmV40.3 dB00
24LockedQAM25612549000000 Hz6.3 dBmV40.3 dB00
 

Upstream Bonded Channels

ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA91280 Ksym/sec39600000 Hz48.3 dBmV
2LockedATDMA15120 Ksym/sec35600000 Hz46.5 dBmV
3LockedATDMA25120 Ksym/sec29200000 Hz45.8 dBmV
4LockedATDMA35120 Ksym/sec22800000 Hz44.8 dBmV
5LockedATDMA45120 Ksym/sec16400000 Hz44 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV