Do these power levels look normal?
 

Just asking for a friend who is having issues right now with his connection.


https://www.cableforum.co.uk/images/...2016/01/31.png

Re: Do these power levels look normal?
 

There is a problem with frequency 561

Re: Do these power levels look normal?
 

Those carriers are 6mhz wide not 8, that's from an American CATV system?

Re: Do these power levels look normal?
 

He has 250 meg with Comcast and i wasn't entirely sure who else to ask if this was bad or not

Re: Do these power levels look normal?
 

There's definitely some "suckout" around 561-567

Re: Do these power levels look normal?
 

He managed to get a technician to come out though on there end there was nothing wrong and his internet keeps going between 275-280 to 2 in a matter of minuets

Re: Do these power levels look normal?
 

There is something wrong

Re: Do these power levels look normal?
 

Very wrong


https://www.cableforum.co.uk/images/...2016/01/16.jpg

Re: Do these power levels look normal?
 

Looks wider than that as the group of unlocked channels from 531 to 549 indicate. An incorrectly terminated cable is the most likely cause. Such a cable acts as a tuned circuit and can cause severe signal loss over a restricted range.

To the OP, does the installation have any splitters and/or unconnected cables in the house?

Re: Do these power levels look normal?
 

I said around not limited to :) As I'm not sure what downstream setup Comcast uses I didn't mention the unlocked channels as there may be 16 down streams available but the modems only use 12

Re: Do these power levels look normal?
 

I'm 95% sure he just has one cable going straight into his modem and that's it

Re: Do these power levels look normal?
 

The technician who visited needs retraining.

4 downstream channels, channels 2 - 5 on that list, are so broken they can't even be locked.

Channels 6 and 7 are way out of spec, channel 6 so much so it's basically unusable.

I recommend your friend registers at http://www.dslreports.com and then posts in https://www.dslreports.com/forum/comcastdirect so that he can get help from Comcast directly :)

---------- Post added at 12:47 ---------- Previous post was at 12:43 ----------

vm_tech / jb66 I'm sure you guys will appreciate Comcast cramming 4 x 6.4MHz 64QAM upstreams into a US DOCSIS subsplit, 5-40MHz returns :)

14.1MHz - 39.7MHz is solid 64QAM returns. How easy do you guys have it with your 5-50MHz, 5-65MHz and on newer/upgraded plant 5-85MHz returns?

Re: Do these power levels look normal?
 

Going down as low as 14mhz is asking for trouble unless it's a squeaky clean network! Unfortunately I work on a 42mhz network with 1 1.6 carrier 1 3.2 and 3 (sometimes 2 depending on node) 6.4!

Re: Do these power levels look normal?
 

He got a second tech out coming Saturday since the first didn't fix anything but i will certainly send him that link thank you.

Re: Do these power levels look normal?
 

24 channels on this system. Poster's mate is using a 16 channel modem. :)