500M High upload power following planned maintenance

david_w2k · 02-07-2020, 23:06

Hello
Will give Virgin a call but thought i'd ask out of interest. There was some planned maintenance last week which caused an outage of around 3 hours this week.

Since then my upstream power levels are high(50-51) and my BB quality graph now seems to have very small amounts of packet loss. Could the 2 be related?

Never had a power issue before even during hot days

spiderplant · 02-07-2020, 23:16

The change to upstream power may well be related to the maintenance, but 50-51 is fine. It won't cause packet loss. I'd only start getting concerned at 58-ish.

david_w2k · 02-07-2020, 23:56

Quote:

Originally Posted by spiderplant

The change to upstream power may well be related to the maintenance, but 50-51 is fine. It won't cause packet loss. I'd only start getting concerned at 58-ish.

Ah ok nice one, I thought 51 was the max. I’d noticed some video conference stutters etc which is why I checked. Maybe modem/router needs a reboot

spiderplant · 03-07-2020, 00:01

51 is the maximum recommended for a new installations. It leaves plenty of leeway in case the signal degrades over time. The absolute limit is 61.

david_w2k · 03-07-2020, 00:11

Quote:

Originally Posted by spiderplant

51 is the maximum recommended for a new installations. It leaves plenty of leeway in case the signal degrades over time. The absolute limit is 61.

Cool, good to know! Appreciate the advice

jb66 · 03-07-2020, 01:44

Quote:

Originally Posted by spiderplant

The change to upstream power may well be related to the maintenance, but 50-51 is fine. It won't cause packet loss. I'd only start getting concerned at 58-ish.

You can't get a 58 upstream when 4 upstreams are locked on, the hub only goes up to 51db on QAM64 ATDMA x4 so 51db is a fault

---------- Post added at 00:44 ---------- Previous post was at 00:43 ----------

Quote:

Originally Posted by spiderplant

51 is the maximum recommended for a new installations. It leaves plenty of leeway in case the signal degrades over time. The absolute limit is 61.

Maybe in 2015!

https://volpefirm.com/speeding-upstream-part-ii/

spiderplant · 03-07-2020, 09:59

Quote:

Originally Posted by jb66

You can't get a 58 upstream when 4 upstreams are locked on, the hub only goes up to 51db on QAM64 ATDMA x4 so 51db is a fault

Thanks, I stand corrected

david_w2k · 03-07-2020, 10:14

Thanks both i'll keep an eye on it! So far havent had a modem reset and also the packet loss has gone. Normally would say leave it until there is an issue rather than going off power levels but I assume at some point it is going to reset?

SnoopZ · 03-07-2020, 10:22

You have tried doing the obvious and turning hub off and on again?

david_w2k · 03-07-2020, 12:18

Quote:

Originally Posted by SnoopZ

You have tried doing the obvious and turning hub off and on again?

Yeah and the power levels are the same but there has not been any further packet loss. Currently connection working perfectly which is great, will see if the power levels cause an issue.

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 46200000 5.075 5120 64 qam 3
2 60300000 5.1 5120 64 qam 1
3 39400000 5.075 5120 64 qam 4
4 53700000 5.1 5120 64 qam 2

Acquired Downstream Channel (Hz)
322750000
Locked
Ranged Upstream Channel (Hz)
46200000
Locked
Provisioning State
Online

david_w2k · 12-08-2020, 11:41

Hi all. Just to loop back on this, I had no further issues so I guess the packet loss problem was a one off. Power levels have been sat at 51 when I have checked periodically but had no resets despite the hot weather - was expecting an issue with the heatwave!

david_w2k · 17-08-2020, 13:07

Spoke too soon. Now stepped down to 16 QAM and pretty much not working at all today suddenly. Assume I'll need an engineer!

Sephiroth · 22-08-2020, 10:43

As a matter of interest, what are your downstream levels? If they are low then two possibilities immediately come to mind:

1/
Your coax cable may need tightening at both ends;

2/
The maintenance involved moving your tap point in the street cabinet and it got moved to one with higher attenuation.

If your downstream power levels are not lower than -3 and indeed are above zero, then there is a definite issue on the VM side. It’s worth checking with your neighbours and let us know what’s happening with them.

david_w2k · 08-01-2021, 13:54

Quote:

Originally Posted by Sephiroth

As a matter of interest, what are your downstream levels? If they are low then two possibilities immediately come to mind:

1/
Your coax cable may need tightening at both ends;

2/
The maintenance involved moving your tap point in the street cabinet and it got moved to one with higher attenuation.

If your downstream power levels are not lower than -3 and indeed are above zero, then there is a definite issue on the VM side. It’s worth checking with your neighbours and let us know what’s happening with them.

Hello!
Apologies I missed your reply previously Sephiroth. Until December we hadnt had any further issues. Recently though have had some short outages which I assume is due to High Upload power? Below is an example of the error - it occured yesterday but no real impact given how short it was but other times it takes a little longer to recover.

All other times it works perfectly and the pre/post RS errors only increase during these short issues. The Downstream power levels look fine.

I did try calling VM when I had a free minute yesterday but was on hold for over 30 minutes and didnt fancy waiting longer to try and explain an intermittent low impact fault! However it would be good to resolve it in case it gets worse!

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID

1 46200000 51 5120 64 qam 3
2 60299927 51 5120 64 qam 1
3 53699980 51 5120 64 qam 2
4 39399937 50.8 5120 64 qam 4

1 202750000 4.6 40 256 qam 9
2 210750000 4.5 40 256 qam 10
3 218750000 4.4 40 256 qam 11
4 226750000 4.4 40 256 qam 12
5 234750000 4.4 40 256 qam 13
6 242750000 4.4 40 256 qam 14
7 250750000 4.5 40 256 qam 15
8 258750000 5 40 256 qam 16
9 266750000 5.1 40 256 qam 17
10 274750000 5.3 40 256 qam 18
11 282750000 5.6 40 256 qam 19
12 290750000 5.8 40 256 qam 20
13 298750000 5.9 40 256 qam 21
14 306750000 5.6 40 256 qam 22
15 314750000 6.1 40 256 qam 23
16 322750000 6.3 40 256 qam 24
17 330750000 6 40 256 qam 25
18 370750000 5.5 40 256 qam 26
19 378750000 5.5 40 256 qam 27
20 386750000 5.5 40 256 qam 28
21 394750000 5.8 40 256 qam 29
22 402750000 5.5 40 256 qam 30
23 410750000 5.6 40 256 qam 31
24 418750000 5.5 40 256 qam 32

1 Locked 40.9 32863 21093
2 Locked 40.3 33379 18862
3 Locked 40.3 32795 20048
4 Locked 40.3 31763 18213
5 Locked 40.3 29799 16977
6 Locked 40.3 28769 16129
7 Locked 40.3 27735 15435
8 Locked 40.3 23769 13025
9 Locked 40.3 20678 12559
10 Locked 40.9 17514 12379
11 Locked 40.9 13665 12630
12 Locked 40.9 11206 13264
13 Locked 40.3 10410 14847
14 Locked 40.9 7795 14867
15 Locked 40.9 5352 6962
16 Locked 40.9 3986 7302
17 Locked 40.9 3598 14428
18 Locked 40.3 1219 7048
19 Locked 40.9 1369 7820
20 Locked 40.9 3180 10157
21 Locked 40.9 4472 10394
22 Locked 40.3 4403 10815
23 Locked 40.3 1849 11156
24 Locked 40.3 730 9851

Time

Priority

Description

07/01/2021 13:07:22

Error

DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 07:50:1

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 07:50:1

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 07:50:1

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 07:49:59

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 07:49:59

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 07:49:59

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:44

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:44

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:44

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:42

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:42

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:42

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

07/01/2021 05:13:42

Warning!

RCS Partial Service;CM-MAC=xxx:9b;CMTS-MAC=xxx;CM-QOS=1.1;CM-VER=3.0;

jb66 · 08-01-2021, 14:45

3 of your upstream is at max transmit I think you need less attenuation