100M : Changing power levels

[borrissey]

My power levels seem to be changing a lot. would this cause the break up on HD TV channels and the odd disconnect I've been expriencing?

I'll post my changing power levels in here:

18.15

Downstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 77 55616000 Kbits/sec 299000000 Hz -4.1 dBmV 34.3 dB Hybrid
Locked QAM256 78 55616000 Kbits/sec 307000000 Hz -4.3 dBmV 34.5 dB Hybrid
Locked QAM256 79 55616000 Kbits/sec 315000000 Hz -4.3 dBmV 34.8 dB Hybrid
Locked QAM256 80 55616000 Kbits/sec 323000000 Hz -4.7 dBmV 35.0 dB Hybrid
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Upstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power
Locked ATDMA 5 20480 Kbits/sec 45800000 Hz 52.5 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

18.35

Downstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 77 55616000 Kbits/sec 299000000 Hz -3.1 dBmV 37.9 dB Hybrid
Locked QAM256 78 55616000 Kbits/sec 307000000 Hz -3.4 dBmV 38.0 dB Hybrid
Locked QAM256 79 55616000 Kbits/sec 315000000 Hz -3.5 dBmV 37.9 dB Hybrid
Locked QAM256 80 55616000 Kbits/sec 323000000 Hz -3.8 dBmV 38.0 dB Hybrid
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Upstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power
Locked ATDMA 5 20480 Kbits/sec 45800000 Hz 50.8 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

18.40

Downstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 77 55616000 Kbits/sec 299000000 Hz -4.1 dBmV 35.9 dB Hybrid
Locked QAM256 78 55616000 Kbits/sec 307000000 Hz -4.4 dBmV 36.1 dB Hybrid
Locked QAM256 79 55616000 Kbits/sec 315000000 Hz -4.3 dBmV 36.3 dB Hybrid
Locked QAM256 80 55616000 Kbits/sec 323000000 Hz -4.7 dBmV 36.2 dB Hybrid
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Upstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power
Locked ATDMA 5 20480 Kbits/sec 45800000 Hz 51.5 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

[craigj2k12]

your SNR is getting quite low, so there could be noise coming from somewhere

[Sephiroth]

This is likely to be a dodgy street box amplifier (evidenced by the varyying power levels).

There could, of course, be a poor connection somewhere that is just about making. So make sure your coax cables are tight at each end. It could also be a dying SH but this is unlikely. It's the first thing a field engineer will change, usually.

Otherwise it's a network team job (not an ordinary field engineer)

[borrissey]

So far I've had 4 techs here to sort the problem. 2 ordinary techs, a senior tech, then my head of area tech. but it's still happening. They've changed taps at the cab, checked levels etc.

Last visit was from my head area tech geezer in his 60's. In the box outside on my wall he changed the active splitter and all the connections on the wires. But the same thing is still happening, break up on the HD channels and the odd disconnection with wired and wireless internet connections.

[Sephiroth]

When everything else is OK, and especially when levels are changing, it leads back to the street cabinet amplifier. IMO.

[borrissey]

Yeah I guess they try the cheaper options first to see if that sorts it...

[philipp]

Has your neighbours mention anything? Are there have the same problem? Mention "CARDY" to the local techs. Its a tool where they can look at surrounding equipment after that identified the cab you are on assuming all areas have the same software. They can distinguish what is causing the problem e.g. the amp or if its your drop cable , etc.

[borrissey]

Guy next door said he's had some break up on the HD channels when I spoke to him the other day, he hadn't reported it.

TiVo box upstairs up from 48.

Mod:Picture removed due to showing MAC/SERIAL/CN

TiVO box downstairs up from 44.

Mod:Picture removed due to showing MAC/SERIAL/CN

[babis3g]

how are the power levels in the morning???are more stable??

if they change in the morning it could be from the cabinet or if they steady other off peak times it could be due to traffic which cost more noise ratio

[craigj2k12]

dont let thenry see those mac addresses :P

[Sephiroth]

If this is a block of flats, try to find the incoming splitter and see what you can see. Are you a long way from the street cabinet?

[Dash: CF noob]

Different QAMs is that normal?

[General Maximus]

Originally Posted by Dash: CF noob

Different QAMs is that normal?

good point dude, I didnt notice that. I dont think it would make that much difference. You would see a difference in speed but I dont know what sort of throughput tv needs. I suppose if it works, then it works. You cant watch tv any faster than real time

[Sephiroth]

My Tivo has different QAMs; I think the video is 64QAM and the Broadband 256QAM.

But the Tivo Return Power at 58 dBmv confirms what the modem stats are showing; there is attenuation on the line. This could be due to the street cabinet as I indicated earlier or if this is a block of flats, poor distribution (splitting).

[borrissey]

I live in a house have two phone lines, 2 TiVos, V HD and SuperHub. I'm about 400 metres from my cabinet.

TiVo Upstairs photo taken an hour ago.



TiVo Downstairs taken an hour ago.




Active Splitter they fitted a few months ago.



My VM Cab.



11.25

Downstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 77 55616000 Kbits/sec 299000000 Hz -1.1 dBmV 39.1 dB Hybrid
Locked QAM256 78 55616000 Kbits/sec 307000000 Hz -1.5 dBmV 39.0 dB Hybrid
Locked QAM256 79 55616000 Kbits/sec 315000000 Hz -1.7 dBmV 38.8 dB Hybrid
Locked QAM256 80 55616000 Kbits/sec 323000000 Hz -1.9 dBmV 38.6 dB Hybrid
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Upstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power
Locked ATDMA 5 20480 Kbits/sec 45800000 Hz 49.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

11.30

Downstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 77 55616000 Kbits/sec 299000000 Hz -1.3 dBmV 39.0 dB Hybrid
Locked QAM256 78 55616000 Kbits/sec 307000000 Hz -1.5 dBmV 39.1 dB Hybrid
Locked QAM256 79 55616000 Kbits/sec 315000000 Hz -1.8 dBmV 38.9 dB Hybrid
Locked QAM256 80 55616000 Kbits/sec 323000000 Hz -2.0 dBmV 38.7 dB Hybrid
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 0.0 dB Unknown
Upstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power
Locked ATDMA 5 20480 Kbits/sec 45800000 Hz 49.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
Unlocked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV