final check before signing new contract

[2tw2]

Hi all

We have had engineers out to sort the downstream power (too low then too high!) and the SNR

Just checking that the the PLC Power for Channel 33 is now OK before we sign the new contract - thanks for help

3.1 Downstream channels

Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)

33

Locked

38

-7.2

2496975759

1216841

The overall downstream power and SNR are now OK I think

3.0 Downstream channels

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

4	163000000	4.500000	37.636276	QAM256	4
1	139000000	5.300003	37.636276	QAM256	1
2	147000000	4.800003	36.609653	QAM256	2
3	155000000	4.699997	36.386890	QAM256	3
5	171000000	3.900002	37.636276	QAM256	5
6	179000000	2.900002	37.636276	QAM256	6
7	187000000	2.200001	37.636276	QAM256	7
8	195000000	1.700001	38.605377	QAM256	8
9	203000000	1.400002	38.605377	QAM256	9
10	211000000	1.599998	38.605377	QAM256	10
11	219000000	1.700001	38.605377	QAM256	11
12	227000000	1.799999	38.605377	QAM256	12
13	235000000	1.500000	38.605377	QAM256	13
14	243000000	1.299999	38.605377	QAM256	14
15	251000000	1.500000	37.636276	QAM256	15
16	259000000	1.900002	38.605377	QAM256	16
17	267000000	1.900002	38.605377	QAM256	17
18	275000000	2.099998	38.983261	QAM256	18
19	283000000	2.299999	38.983261	QAM256	19
20	291000000	2.400002	38.983261	QAM256	20
21	299000000	1.900002	38.605377	QAM256	21
22	307000000	1.000000	37.636276	QAM256	22
23	315000000	0.299999	37.355988	QAM256	23
24	323000000	-0.099998	37.355988	QAM256	24
25	331000000	-0.099998	37.355988	QAM256	25
26	339000000	-0.299999	37.636276	QAM256	26
27	347000000	-0.599998	37.636276	QAM256	27
28	355000000	-0.599998	37.355988	QAM256	28
29	363000000	-0.799999	37.355988	QAM256	29
30	371000000	-0.900002	37.355988	QAM256	30
31	379000000	-0.599998	37.636276	QAM256	31

3.0 Downstream channels

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

4	Locked	37.636276	0	0
1	Locked	37.636276	0	0
2	Locked	36.609653	2	0
3	Locked	36.386890	3	0
5	Locked	37.636276	1	0
6	Locked	37.636276	0	0
7	Locked	37.636276	0	0
8	Locked	38.605377	0	0
9	Locked	38.605377	0	0
10	Locked	38.605377	0	0
11	Locked	38.605377	0	0
12	Locked	38.605377	0	0
13	Locked	38.605377	0	0
14	Locked	38.605377	0	0
15	Locked	37.636276	0	0
16	Locked	38.605377	0	0
17	Locked	38.605377	0	0
18	Locked	38.983261	1	0
19	Locked	38.983261	0	0
20	Locked	38.983261	0	0
21	Locked	38.605377	0	0
22	Locked	37.636276	0	0
23	Locked	37.355988	0	0
24	Locked	37.355988	2	0
25	Locked	37.355988	8	0
26	Locked	37.636276	5	0
27	Locked	37.636276	9	0
28	Locked	37.355988	16	0
29	Locked	37.355988	12	0
30	Locked	37.355988	12	0
31	Locked	37.636276	17	0

3.1 Downstream channels

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

33

96

4K

1880

QAM4096

759

[unisoft · Accepted solution]

DOCSIS 3.1 power level is not acceptable at -7.2 and needs a tech visit as the uncorrectable count proves. SNR is OK on it and others. The 3.0 channels are all within specs.

[2tw2]

We have had 4-5 engineer visits about this and they fix one thing but leave another issue!

Refreshed and it is now -6.8

3.1 Downstream channels

Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)

33

Locked

38

-6.8

2522447942

1238000

[2tw2]

OK - have things settled down now? The 3.1 downstream power is now - 5.9 dBmV and the lowest SNR is 36.6 dB. Upstream looks OK.

Thanks so much for help

3.0 Downstream channels

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

4	163000000	5.500000	37.355988	QAM256	4
1	139000000	6.199997	38.983261	QAM256	1
2	147000000	5.800003	37.355988	QAM256	2
3	155000000	5.699997	36.609653	QAM256	3
5	171000000	4.900002	37.636276	QAM256	5
6	179000000	3.900002	38.605377	QAM256	6
7	187000000	3.099998	38.983261	QAM256	7
8	195000000	2.700001	38.983261	QAM256	8
9	203000000	2.400002	38.983261	QAM256	9
10	211000000	2.599998	40.366287	QAM256	10
11	219000000	2.700001	40.366287	QAM256	11
12	227000000	2.599998	38.983261	QAM256	12
13	235000000	2.400002	38.983261	QAM256	13
14	243000000	2.200001	38.983261	QAM256	14
15	251000000	2.500000	38.983261	QAM256	15
16	259000000	3.099998	38.983261	QAM256	16
17	267000000	2.900002	38.983261	QAM256	17
18	275000000	3.200001	38.605377	QAM256	18
19	283000000	3.299999	40.366287	QAM256	19
20	291000000	3.299999	40.366287	QAM256	20
21	299000000	2.900002	38.983261	QAM256	21
22	307000000	1.900002	38.983261	QAM256	22
23	315000000	1.200001	38.605377	QAM256	23
24	323000000	0.799999	38.605377	QAM256	24
25	331000000	0.599998	38.605377	QAM256	25
26	339000000	0.500000	38.983261	QAM256	26
27	347000000	0.400002	38.605377	QAM256	27
28	355000000	0.200001	38.983261	QAM256	28
29	363000000	0.000000	38.983261	QAM256	29
30	371000000	0.000000	38.983261	QAM256	30
31	379000000	0.200001	38.983261	QAM256	31

3.0 Downstream channels

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

4	Locked	37.355988	339	0
1	Locked	38.983261	275	0
2	Locked	37.355988	662	0
3	Locked	36.609653	729	0
5	Locked	37.636276	202	0
6	Locked	38.605377	204	0
7	Locked	38.983261	215	0
8	Locked	38.983261	210	0
9	Locked	38.983261	217	0
10	Locked	40.366287	144	0
11	Locked	40.366287	145	0
12	Locked	38.983261	162	0
13	Locked	38.983261	241	0
14	Locked	38.983261	349	0
15	Locked	38.983261	312	0
16	Locked	38.983261	189	0
17	Locked	38.983261	182	0
18	Locked	38.605377	189	0
19	Locked	40.366287	134	0
20	Locked	40.366287	175	0
21	Locked	38.983261	252	0
22	Locked	38.983261	461	0
23	Locked	38.605377	795	0
24	Locked	38.605377	1160	0
25	Locked	38.605377	1589	0
26	Locked	38.983261	1778	0
27	Locked	38.605377	2212	0
28	Locked	38.983261	2746	0
29	Locked	38.983261	3154	0
30	Locked	38.983261	3299	0
31	Locked	38.983261	2960	0

3.1 Downstream channels

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

33

96

4K

1880

QAM4096

759

3.1 Downstream channels

Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)

33

Locked

39

-5.9

811987495

1039768

[Miggle]

that figure still isnt right though, when you compare to what you get for the 3.0 channels. Might be interference on that channel for the 3.1. Is suspect your figure will fluctuate and could go back to -7.x again.

I would ask the VM engineer to escalate to NETWORKS team if they can't resolve it.

[2tw2]

Thank you! Will do

[2tw2]

Update for Miggle

Well we still had the DOCSYS 3.1 download channel out of spec as you noted  - so a 3dB forward path attenuator was fitted today to replace the 6 dB one fitted last week which threw the 3.1 downstream channel out of spec while sorting out the 3.0 channels.

All downstream and upstream channels now seem to be in spec.

Not sure why it has taken so long and 5 engineers! I am very grateful for the forum guidance and what the router readings should be

[Tom_W1]

Hi @2tw2 thanks for your post here in the Community although I'm very sorry to hear of your concerns raised.

I've ran some checks for you, and there doesn't seem to be any issues with any levels being out of specifications as things stand.

I appreciate that they might not have been before this time, but I'm glad to see the issues are now resolved.

If you do need any further help, please don't hesitate to let me know!

Many thanks

[2tw2]

Thanks - it all seems fairly stable now after the 6 dB attenuator was swapped for a 3 dB one... Fingers crossed

Hope it is Ok for Channel 3.1 downstream to be at -3.8? And hope the Uncorrectables figure is OK ish. Had 1 x T3 timeouts on  6.9.22

3.1 Downstream channels

Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)

33

Locked

39

-3.8

1138905741

1714536

[Gareth_L]

Hello 2tw2

I have just checked the Hub and its all in range here now.

If you need anything else, please pop back on here.

Gareth_L