Hub 5 High Download Errors

[grunkp]

Just noticed that most of the Downstream Channels have a high number of Pre RS Errors a few downstream channels also have high Post RS Errors.

The downstream corrected errors and the uncorrected errors are in the 100's of millions and increasing.

The Hub5 LOg shows frequent CMS Notices

CM-STATUS message sent. Event Type Code: -  toggling between 24 and 16.

The Upstream Channels show zero errors

Modem was rebooted some 8hrs ago.

Hub 5 also refuses to go into Modem Mode !

Is the HUB 5 on the way out or is there an issue at the street cab ?

3.0 Downstream channels

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

1	586000000	1	34	QAM 256	29
2	362000000	2.1	35	QAM 256	1
3	370000000	2.2	37	QAM 256	2
4	378000000	2.4	37	QAM 256	3
5	386000000	2.2	36	QAM 256	4
6	394000000	1.9	31	QAM 256	5
7	402000000	1.9	35	QAM 256	6
8	410000000	1.6	34	QAM 256	7
9	418000000	1.4	31	QAM 256	8
10	426000000	1.1	29	QAM 256	9
11	434000000	0.9	31	QAM 256	10
12	442000000	1.1	31	QAM 256	11
13	450000000	1.3	33	QAM 256	12
14	458000000	1.1	32	QAM 256	13
15	466000000	1.5	32	QAM 256	14
16	546000000	0.7	34	QAM 256	24
17	554000000	0.8	32	QAM 256	25
18	562000000	0.9	36	QAM 256	26
19	570000000	0.7	36	QAM 256	27
20	578000000	0.7	35	QAM 256	28
21	602000000	0.9	32	QAM 256	31
22	610000000	0.6	38	QAM 256	32
23	618000000	0.1	38	QAM 256	33
24	626000000	0.4	38	QAM 256	34
25	634000000	0.4	34	QAM 256	35
26	658000000	0.3	28	QAM 256	36
27	666000000	0.2	34	QAM 256	37
28	674000000	0.3	34	QAM 256	38
29	682000000	0	30	QAM 256	39
30	690000000	0.5	32	QAM 256	40

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

1	Locked	34	339806	0
2	Locked	35	207	8
3	Locked	37	63	0
4	Locked	37	77	1
5	Locked	36	32	0
6	Locked	31	139444925	117662
7	Locked	35	448	2
8	Locked	34	7181	0
9	Locked	31	8815490	1
10	Locked	29	214082988	9
11	Locked	31	7541814	13479
12	Locked	31	186655325	18285537
13	Locked	33	5304476	0
14	Locked	32	2495161	0
15	Locked	32	838083	0
16	Locked	34	155318	0
17	Locked	32	1971676	0
18	Locked	36	73	0
19	Locked	36	142	0
20	Locked	35	1997	0
21	Locked	32	7251107	0
22	Locked	38	5	0
23	Locked	38	13	0
24	Locked	38	21	0
25	Locked	34	4267	0
26	Locked	28	706277852	104257
27	Locked	34	61264	0
28	Locked	34	344476	0
29	Locked	30	156361665	3566
30	Locked	32	41667493	383130

3.1 Downstream channels

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

41

94

4K

1840

QAM 4096

1108

3.1 Downstream channels

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

41

Locked

34

-1.6

196932617

192767441

[grunkp]

Yes I though that message rather odd. The timestamps in the logs are still showing BST !

Every downstream channel now has PRE and POST errors.

My gut feeling is that its the Hub, but I'm no expert on this sort of technology.

[grunkp]

I managed to get around to checking the cable joints and found two that were just finger tight. I locked both down with a spanner - they must come loose with cable movement.

The Downstream PRE and POST errors dropped like a stone and the CM-STATUS messages stopped. The Hub rebooted normally back into Router mode when instructed to do so.

After 3 hours of uptime I've noticed the odd Downstream PRE error but no POST errors and no CM-STATUS msgs.

However the Downstream Correctable errors remains very high but the Uncorrectable errors are zero. From previous posts that may indicate that the hub requires replacing.

Here are the latest hub stats.

3.0 Downstream channels

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

1	586000000	1.2	40	QAM 256	29
2	362000000	2.5	40	QAM 256	1
3	370000000	2.4	40	QAM 256	2
4	378000000	2.4	40	QAM 256	3
5	386000000	2.2	40	QAM 256	4
6	394000000	2.1	40	QAM 256	5
7	402000000	2.3	40	QAM 256	6
8	410000000	1.9	40	QAM 256	7
9	418000000	1.6	40	QAM 256	8
10	426000000	1.5	40	QAM 256	9
11	434000000	1.3	39	QAM 256	10
12	442000000	1.5	40	QAM 256	11
13	450000000	1.7	40	QAM 256	12
14	458000000	1.4	40	QAM 256	13
15	466000000	1.3	40	QAM 256	14
16	474000000	1.3	40	QAM 256	15
17	482000000	1.4	40	QAM 256	16
18	490000000	1.7	40	QAM 256	17
19	570000000	0.9	40	QAM 256	27
20	578000000	1.1	40	QAM 256	28
21	594000000	0.7	40	QAM 256	30
22	602000000	0.7	40	QAM 256	31
23	610000000	0.8	40	QAM 256	32
24	618000000	0.5	40	QAM 256	33
25	626000000	0.6	40	QAM 256	34
26	634000000	0.3	40	QAM 256	35
27	658000000	0.2	40	QAM 256	36
28	666000000	0.1	40	QAM 256	37
29	674000000	0.1	40	QAM 256	38
30	682000000	0.3	40	QAM 256	39
31	690000000	0.8	40	QAM 256	40

3.0 Downstream channels

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

1	Locked	40	1	0
2	Locked	40	0	0
3	Locked	40	0	0
4	Locked	40	0	0
5	Locked	40	0	0
6	Locked	40	0	0
7	Locked	40	0	0
8	Locked	40	0	0
9	Locked	40	0	0
10	Locked	40	0	0
11	Locked	39	0	0
12	Locked	40	0	0
13	Locked	40	0	0
14	Locked	40	0	0
15	Locked	40	0	0
16	Locked	40	1	0
17	Locked	40	0	0
18	Locked	40	0	0
19	Locked	40	0	0
20	Locked	40	0	0
21	Locked	40	0	0
22	Locked	40	1	0
23	Locked	40	1	0
24	Locked	40	1	0
25	Locked	40	0	0
26	Locked	40	1	0
27	Locked	40	1	0
28	Locked	40	0	0
29	Locked	40	0	0
30	Locked	40	1	0
31	Locked	40	2	0

3.1 Downstream channels

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

41

94

4K

1840

QAM 4096

1108

3.1 Downstream channels

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

41

Locked

40

-1.7

102893712

0

3.0 Upstream channels

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

0	49600000	41	5120	QAM 64	5
1	43100000	40.5	5120	QAM 64	6
2	36600000	40.3	5120	QAM 64	7
3	30100000	40.3	5120	QAM 64	8
4	23600000	39.8	5120	QAM 64	10

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

13

10.4

36.2

2K

QAM 256

 

3.1 Upstream channels

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

13

OFDMA

208

74000000

0

0

[Tudor]

Those figures are very good. The correctable are always higher for me too. Only thing I can see is that the  downstream power levels are a bit low, but in spec. Do you have a forward path attenuator on the back of your hub or a splitter for a TV box?

[grunkp]

There is a terminator/joint block on the incoming coax, but the 2nd outlet is capped. We have 3 coax coming off the outside brown box but only one is in use for the Hub, the other two have terminator blocks attached.

Appreciate your advice

J

[Tudor]

Those ‘terminator’ blocks are splitters a they can act as an attenuator. Each ‘leg’ of the splitter is usually marked with a dBm value that is imposed on the line. The need removing and the incoming coax should just have a female-to-female joiner that does not impose any load on the signal. You can get them from Amazon or B&Q.

[grunkp]

The label on it says Vocom VQ330 Isolator, and no dBm values marked, so I'm guessing that it is nothing more than

just an isolator and is not attenuating the signal.

[grunkp]

Hmmmm, to get access to the isolator involved moving it and the associated cables. Suddenly i noticed a whole lot of Pre and Post RS errors etc - sounds like a bad connection or cable end.

[grunkp]

Well,Well. What is this!!

Powered the Hub down and unscrewed the two cables attached to the isolator. The incoming cable and and the corresponding socket on the isolator were covered in a gluey clear substance, (Reminds me of electrical water sealing gel). I've attempted to clean it off with Abs Alcohol, not easy, and brightened up the copper centre. Removed the Isolator and used a straight connector to join the cables. Powered the Hub up and no errors as such.

I guess a call to CS is now in order to arrange an engineer visit to check that its not an incoming cable issue (maybe redo the connector) and to put a new isolator in place.

[Matthew_ML]

Hey grunkp, thank you for reaching out today and I am so sorry to hear about your connection issues.

I've taken a look from our side everything looks great, no issues at all.

Levels are great.

How has it been over the weekend?

Also is the isolator place damaged? 

[grunkp]

Hi Matt

After 2 days of uptime there are some 20-30 Pre RS errors on some of the hi numbered downstream channels (those with the lowest power levels) - see stats below. Apart from that the Hub appears to be behaving and download speeds are good as are the BQM graphs

I could do with a new isolator though and a new cable F connector on the incoming cable as its proving virtually impossible to remove the 'gunge' completely from the Vocom VQ330 and the F connector. Abs Alcohol wont budge it. I also suspect that the gunge is maybe now acting as a leakage path of sorts !

Jeff

3.0 Downstream channels

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

1	362000000	2.9	40	QAM 256	1
2	370000000	2.7	40	QAM 256	2
3	378000000	2.7	40	QAM 256	3
4	386000000	2.5	40	QAM 256	4
5	394000000	2.5	40	QAM 256	5
6	402000000	2.7	40	QAM 256	6
7	410000000	2.3	40	QAM 256	7
8	418000000	1.9	40	QAM 256	8
9	426000000	1.9	40	QAM 256	9
10	434000000	1.7	40	QAM 256	10
11	442000000	1.9	40	QAM 256	11
12	450000000	2.1	40	QAM 256	12
13	458000000	1.7	40	QAM 256	13
14	466000000	1.7	40	QAM 256	14
15	474000000	1.7	40	QAM 256	15
16	482000000	1.8	40	QAM 256	16
17	490000000	2.1	40	QAM 256	17
18	498000000	2	40	QAM 256	18
19	506000000	1.6	40	QAM 256	19
20	514000000	1.6	40	QAM 256	20
21	522000000	1.5	40	QAM 256	21
22	530000000	1.5	40	QAM 256	22
23	610000000	1.3	40	QAM 256	32
24	618000000	0.9	40	QAM 256	33
25	626000000	1.1	40	QAM 256	34
26	634000000	0.9	40	QAM 256	35
27	658000000	0.1	40	QAM 256	36
28	666000000	0.3	40	QAM 256	37
29	674000000	0.7	40	QAM 256	38
30	682000000	0.3	40	QAM 256	39
31	690000000	0.3	40	QAM 256	40

3.0 Downstream channels

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

1	Locked	40	0	0
2	Locked	40	0	0
3	Locked	40	0	0
4	Locked	40	0	0
5	Locked	40	0	0
6	Locked	40	0	0
7	Locked	40	0	0
8	Locked	40	3	0
9	Locked	40	2	0
10	Locked	40	2	0
11	Locked	40	1	0
12	Locked	40	1	0
13	Locked	40	2	0
14	Locked	40	3	0
15	Locked	40	5	0
16	Locked	40	5	0
17	Locked	40	2	0
18	Locked	40	2	0
19	Locked	40	5	0
20	Locked	40	3	0
21	Locked	40	4	0
22	Locked	40	4	0
23	Locked	40	10	0
24	Locked	40	7	0
25	Locked	40	4	0
26	Locked	40	13	0
27	Locked	40	20	0
28	Locked	40	11	0
29	Locked	40	15	0
30	Locked	40	22	0
31	Locked	40	33	0

3.1 Downstream channels

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

41

94

4K

1840

QAM 4096

1108

3.1 Downstream channels

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

41

Locked

40

-1.7

2367085505

0

3.0 Upstream channels

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

0	49600000	41	5120	QAM 64	5
1	43100000	40.5	5120	QAM 64	6
2	36600000	40.3	5120	QAM 64	7
3	30100000	40.3	5120	QAM 64	8
4	23600000	39.8	5120	QAM 64	10

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

13

10.4

36.2

2K

QAM 256

3.1 Upstream channels

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

13

OFDMA

208

74000000

0

0