Just a question here. We have had some maintenance in our area today and I have had a couple of outages this morning. However, I have noticed my down stream values have dropped by about 3-4dbmv from around 8 to around 4. What would explain this and should I be concerned or need to take any action? Also pre and post errors seem to be increasing. I may have to obvioulsy wait until the maintenance has donw with tomorrow but the errors have actually been happening for a few days but I have noticed no affect on my broadband.

The ideal downstream power is 0, so your figures have actually improved. Anything between around -6 and +10 is OK.

Drop could simply be replaced components are of better quality, or they have increased power for more users? PreRS errors can be ignored, it's the PostRS errors that need looked at. Wait until the work is finished and reboot your Hub for a clean slate. Monitor the errors then, and if they mount up then come back and post all your power levels and network log for comment.

Well I did wonder that and I have an attenuator on the back of mine too I was just worried that perhaps I didn't need it any more for example 🙂

I rebooted yesterday evening after the work was confirmed as complete and have noticed pre-rs errors going up (the did not before for weeks at a time sometimes). I will reset again and come back but my power levels are a lot different to what they were to be honest and a bigger spread too..

That's a fairly decent BQM since 12am. PreRS errors are fine, as they have been corrected. It's the PostRS errors that are bad.

Question about downstream values dropping after local maintenance outage

cje85
Trouble shooter
11 months ago
The ideal downstream power is 0, so your figures have actually improved. Anything between around -6 and +10 is OK.
- fizz
  Fibre optic
  11 months ago
  Well I did wonder that and I have an attenuator on the back of mine too I was just worried that perhaps I didn't need it any more for example 🙂
Adduxi
Very Insightful Person
11 months ago
Drop could simply be replaced components are of better quality, or they have increased power for more users? PreRS errors can be ignored, it's the PostRS errors that need looked at. Wait until the work is finished and reboot your Hub for a clean slate. Monitor the errors then, and if they mount up then come back and post all your power levels and network log for comment.
fizz
Fibre optic
11 months ago
I rebooted yesterday evening after the work was confirmed as complete and have noticed pre-rs errors going up (the did not before for weeks at a time sometimes). I will reset again and come back but my power levels are a lot different to what they were to be honest and a bigger spread too..
Adduxi
Very Insightful Person
11 months ago
That's a fairly decent BQM since 12am. PreRS errors are fine, as they have been corrected. It's the PostRS errors that are bad.
fizz
Fibre optic
11 months ago
Thanks adduxi. Looks like I am back to my problems after 4pm again. Had this for about 6 months and 5 engineers and cable repulls could not fix the issue. Keeping an eye on it as modem mode seems to help a lot for me. Will post back tomorrow of stats are rubbish.

fizz

Fibre optic

11 months ago

For reference here are my figures after a reboot at 9pm last night -

3.0 Downstream channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID

1	331000000	3.7	38	QAM 256	25
2	267000000	4.4	38	QAM 256	17
3	275000000	4.2	38	QAM 256	18
4	283000000	4.1	38	QAM 256	19
5	291000000	4.1	38	QAM 256	20
6	299000000	4	38	QAM 256	21
7	307000000	3.8	38	QAM 256	22
8	315000000	3.4	38	QAM 256	23
9	323000000	3.5	38	QAM 256	24
10	339000000	4	38	QAM 256	26
11	347000000	4.3	38	QAM 256	27
12	355000000	4.2	38	QAM 256	28
13	363000000	4.2	38	QAM 256	29
14	371000000	4.4	38	QAM 256	30
15	379000000	4.3	38	QAM 256	31
16	387000000	4	38	QAM 256	32
17	395000000	4	38	QAM 256	33
18	403000000	3.6	38	QAM 256	34
19	411000000	3.4	37	QAM 256	35
20	419000000	3.2	38	QAM 256	36
21	427000000	3.2	37	QAM 256	37
22	435000000	3.3	38	QAM 256	38
23	443000000	3.6	38	QAM 256	39
24	451000000	3.8	38	QAM 256	40
25	459000000	3.7	38	QAM 256	41
26	467000000	3.5	38	QAM 256	42
27	475000000	3.6	38	QAM 256	43
28	483000000	3.5	38	QAM 256	44
29	491000000	3.4	37	QAM 256	45
30	499000000	3.2	37	QAM 256	46
31	507000000	3.1	37	QAM 256	47
32	515000000	2.9	37	QAM 256	48

3.0 Downstream channels

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors

1	Locked	38	0
2	Locked	38	0
3	Locked	38	0
4	Locked	38	0
5	Locked	38	0
6	Locked	38	0
7	Locked	38	0
8	Locked	38	0
9	Locked	38	0
10	Locked	38	0
11	Locked	38	0
12	Locked	38	0
13	Locked	38	3
14	Locked	38	1
15	Locked	38	0
16	Locked	38	0
17	Locked	38	1
18	Locked	38	0
19	Locked	37	0
20	Locked	38	0
21	Locked	37	0
22	Locked	38	0
23	Locked	38	0
24	Locked	38	0
25	Locked	38	0
26	Locked	38	1
27	Locked	38	0
28	Locked	38	1
29	Locked	37	0
30	Locked	37	1
31	Locked	37	0
32	Locked	37	2

3.1 Downstream channels

Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)

159

190

3736

QAM 4096

148

3.1 Downstream channels

Channel ID Locked Status RxMER Data (dB) PLC Power (dBmV) Corrected errors (Active Profile) Uncorrectable errors (Active Profile)

159

Locked

2.4

520684110

3.0 Upstream channels

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

0	49600000	43.8	5120	QAM 64	1
1	43100000	43.8	5120	QAM 64	2
2	36600000	43.8	5120	QAM 64	3
3	30100000	43	5120	QAM 64	4
4	23600000	42.8	5120	QAM 64	5

3.0 Upstream channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

0	ATDMA	0	0	0	0
1	ATDMA	0	0	0	0
2	ATDMA	0	0	0	0
3	ATDMA	0	0	0	0
4	ATDMA	0	0	0	0

3.1 Upstream channels

Channel Channel Width (MHz) Power (dBmV) FFT Type Modulation

38.0

QAM 256

3.1 Upstream channels

Channel Channel Type Number of Active Subcarriers First Active Subcarrier (Hz) T3 Timeouts T4 Timeouts

OFDMA

200

74000000

07-03-2024 21:05:25	warning	DBC-REQ Mismatch Between Calculated Value for P1.6hi Compared to CCAP Provided Value;CM-MAC=:::::;CMTS-MAC=:::::;CM-QOS=1.1;CM-VER=3.1;
07-03-2024 21:05:25	notice	US profile assignment change. US Chan ID: 6; Previous Profile: 13; New Profile: 11 13.;CM-MAC=:::::;CMTS-MAC=:::::;CM-QOS=1.1;CM-VER=3.1;
07-03-2024 21:05:21	notice	REGISTRATION COMPLETE - Waiting for Operational status

Daniel_Et
Forum Team
11 months ago
Hi fizz, thank you for your posts.

We're sorry to hear about the concerns you have 😔

I've taken a look on our side, but I cannot see any issues that could be causing this. How have things been since you last posted?

Please pop back to us at your earliest convenience.

Thank you for your support Adduxi 👍

Regards,
Daniel

fizz
Fibre optic
11 months ago
Hi Daniel,
I didn't really have an issue just that all my stats on the downstream dropped quite dramatically and now I'm getting more prers errors that I used to. Connectivity seems fine in all honesty.
- Matthew_ML
  Forum Team
  11 months ago
  Sorry to hear this, how has the connection been since Monday have you seen am improvment?
- fizz
  Fibre optic
  10 months ago
  Now I am getting issues. Not very often but I am getting critical errors and disconnects occasionally during the evening mainly
  
  26-03-2024 20:34:53 critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
  Also I am still getting creping pre rs errors. Before this maintenance I never really go any. My downstream do seem further apart now so 2 to 6. The disconnects are getting more frequent every day or two..keeping an eye on this but there has defo been a change for the worse since this maintenance took place
  - Sabrina_B
    Forum Team
    10 months ago
    Hi fizz 👋.
    
    Thanks for reaching back out to us, apologies for the issues you are having with your Hub, so that we can assist, we would need to bring you in for a private message. Please look out for the envelope on the top right of your web browser or if you are using a mobile device, it will be located under your profile icon.
    
    Thanks.
    Sabrina
fizz
Fibre optic
10 months ago
well actually there was nothing wrong with it wo there was nothing to improve.. however I have noticed though that sometimes during the day my downstreams drop quite a lot and the pre-rs errors start but I get no descernable difference in service OR in my BQM just in my router stats. I reboot and downstream goes back up and all is well.
Adduxi
Very Insightful Person
10 months ago
The PreRS errors are not an issue, as these are corrected by the Hub, it's the PostRS ones you need to look out for. As for fluctuating power levels, these can be affected by the heat or cold depending on the day. If the BQM is good and your circuit is working, I wouldn't worry about it too much.

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Question about downstream values dropping after local maintenance outage

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