| [Business] Just got biz installed, 16/2, happy so far. :) We'll see how reliable this is long term! But I'm getting the advertised speeds and bursting to about twice the speed in both directions.
I'm impressed at their packet scheduling; latency barely goes up at all during heavy transfers.
I think I mentioned in a prior thread that I was close to the node so I should get a good signal. Well this is definitely the case, to the point that they had to put a 6dB attenuator in line with the SMC box to get the signal to an acceptable level. Wow.
In any case, thank you to those who provided advice and to others who have posted useful information on this forum. It was very helpful.
My signal stats, just for academic purposes:
Downstream Channel
Downstream Frequency 699000000 Hz
Lock Status Locked
Modulation 256 QAM
Symbol Rate 5.360537 Msym/sec
Downstream Power 7.9 dBmV
SNR 38.500 dB
Upstream Channel
Upstream Frequency 36400000 Hz
Lock Status Locked
Modulation 16QAM
Symbol Rate 5120000 sym/sec
Upstream Power 49.7 dBmV
Channel ID 1 |
|
komat
join:2007-11-07
Morgantown, WV | did you have to pay a install fee or did you do a 3year contract |
|
 ropeguruPremium
join:2001-01-25
Mechanicsville, VA | reply to SpottedCat
They MAY still need to do some adjusting. Especially if your upstream increases much more.
But looks like you are doing good for now. |
|
| reply to komat
It's a two year contract; and no install fee. However, they give you 30 days to decide if the service is adequate, so I went for that.
So far so good. |
|
1 edit | reply to ropeguru
said by ropeguru:They MAY still need to do some adjusting. Especially if your upstream increases much more. But looks like you are doing good for now. When they were setting it up they tried a 3dB attenuator, and that wasn't enough so they tried a 6dB attenuator and that fixed the issue.
They left the 3dB attenuator behind though. Should I add that to the line if the upstream power goes up too much? Or should I just call them and let them deal with it if there's problems?
I can expect the signal to be strong; the node is right outside the window and I'm on the *first* tap on the line. On top of that, there are no other devices on my drop; just the cable modem. |
|
ropeguruPremium
join:2001-01-25
Mechanicsville, VA | There is definitely still an issue somewhere as your upstream should not be that high. |
|
| Well, the installer had a PDA that talked to some central Comcast server, which reported statistics on my line. Initially it reported that the signal from my modem was too strong, so he put in the 3dB attenuator. It was still too strong, so he put in the 6dB instead, and then it was fine.
I did a quick check and added the 3dB attenuator to the 6dB; the upstream power actually went *UP* 3dB to compensate. Needless to say I removed it and am just using the 6dB again.
The installer said my numbers were very good, so I'm going to trust him for now if there are no issues. What makes you think it's too high? |
|
 CableToolPoorly Representing MYSELF.Premium
join:2004-11-12 | reply to ropeguru
said by ropeguru:There is definitely still an issue somewhere as your upstream should not be that high. If he is off of the first tap of the run( which he stated he is) then his upstream would be from 42-44dbmv per spec at the tap. Add in a 6db attenuator to drop the forward which means the upstream is most likely at a 43dbmv at the tap. Thus- after a 6db pad- 49dbmv.
There is no adjusting that needs to be done.
To Spotted Cat- Not that it matters but this isnt DSL. Your reliability or speed has nothing to do with where you are in the plant. You could be right off of the node or 3 cascades away.
--
CableTechs.org/"Horrible People with Integrity" |
|
 beachintechThere's sand in my tool bagPremium
join:2008-01-06
kudos:5
 ·Comcast
| reply to ropeguru
said by ropeguru:There is definitely still an issue somewhere as your upstream should not be that high. That's right where I would expect it with a 6db pad right off a node/active.
--
Tech at the Beach.
I speak for myself, not my employer. |
|
ropeguruPremium
join:2001-01-25
Mechanicsville, VA | reply to CableTool
Thanks for the education guys.. |
|
| as Tool said there is no problem. If he is comming off a node/amp/le there is most likely a 26 value tap. you take tap value + unity gain= trsnsmit value at tap. In my system the unity gain is 18. So a 26 value tap should have a transmit of 44. |
|
| reply to SpottedCat
»Comcast High Speed Internet FAQ »How the CMTS determines your modem's transmit power |
|
ropeguruPremium
join:2001-01-25
Mechanicsville, VA | reply to ComTech 4
I got it, I got it...  |
|
|
|
