pete_at_home
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Joined 10 years ago
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Re: Signal Levels now 6dB down following Fibre Node replacement
SNR used to be 40-41dB on all channels. Now many are 38dB which is minimum for reliable 256QAM. US is screaming at 50dB, which agin is theoretically ok, but the HFC plant works best with 40-45dB from the modem. My V6 TV box signal is also well low due to the location of the splitter feeding the modem & then a long cable for the V6. One of the problems is the VM procedure for aligning the HFC has flaws in it (yes I have a copy). The VM contractors did spot another cabinet with signals on the tap bank all a bit low, so he moved them all up one step. Then got called away before doing my drop cable as well. All in all a badly setup area since the new fibre node !! All they need t odo is align that properly, because the RF Amps were correct & not touched.Signal Levels now 6dB down following Fibre Node replacement
Last week (Thursday 14th Aug), there was an outage in my area while VM upgraded the local Fibre Node. Since then my DS levels have dropped by 6dB, and US now sending 6dB higher. In itself this would not sormally be an issue, BUT the SNR on my Hub-5 has definitely degraded on a percentage of the QAM channels. US channels regularly drop back to 32QAM or sometimes 16QAM. Yes, I know the levels are "within the standard VM range", but the Post RS Errors are excessive. Somewhat frustrating for someone who has worked on HFC & Docsis for well over 20 years !! Someone has not aligned the new fibre Node correctly. Guess I have to call customer service & chase through the maze of getting them to understand !! The outage:Re: Hub 5 power levels too high
Downstream levels are slightly high based on VM's install practice, but well within the Docsis Standard (-15dBmV to +15dBmv). Either the network needs aligning properly (most likely), as your local network has too much US attenuation, and not enough DS attenuation !! Chances are other people connected to the same street cabinet have similar issues, but simply haven't noticed !! They could fit a Forward Path Attenuator to your line. This will lower the DS levels leaving the US as they are. If they fit a Wideband attenuator then the DS will drop, but the US levels will increase, leading to possible distortion & more issues !!Re: Worthwhile to Pursue An Engineer/Technician Visit?
Spirit, While VM are sorting their network issues, you should probably check & clean browser clutter on your PC. I have found similar Hub to Computer issues, especially when my browser cache has not been cleared for a while. Try "ccleaner" free version & do a manual cleanup or cookies & history. It should leave your bookmarks, passwords, etc intact. Your Samknows tests are exactly as they should be, so another PC test is to use the Speedtest Windows app instead of a browser to check performance. Pete
