Hitron 4582 Signal Issue

  • ATTENTION! As of November 1, 2020, you are not able to reply to threads 6 months after the thread is opened if there are more than 500 posts in the thread.
    Threads will not be locked, so posts may still be edited by their authors.
    Just start a new thread on the topic to post if you get an error message when trying to reply to a thread.

micahelriley

New Around Here
Hi, can someone help me diagnose signal level issues with my Hitron 4582 please? I'm having wireless and wired connection drops with speed tests varying in results. I can post the tables from the DOCSIS WAN, thank you.
 

Datalink

Regular Contributor
You can copy and post the signal level table, from the DOCSIS WAN ..... Downstream Overview line all the way to the bottom of the OFDM/OFDMA section. Ignore the data that resides above the Downstream line as its specific to the modem and should not be posted in an open forum.

If you happen to be a Rogers customer, look at the front of the modem. If both downstream and upstream LEDs (arrows) are a light blue, that indicates that the modem is using an OFDM downstream channel and an OFDMA upstream channel. OFDM downstream has been in use for almost four years and is usually a stable downstream channel. The OFDMA channel is newly enabled and appears to be causing disconnect issues. That can be confirmed by logging into the modem and looking at the DOCSIS WAN tab, specifically the bottom OFDM/OFDMA overview section. You should see one of the two OFDMA channels enabled.



If you don't have an OFDMA channel enabled, then you have other problems to contend with.
 
Last edited:

micahelriley

New Around Here
Hi, thanks for replying. The IS is Eastlink, but both the up and down are showing blue on the modem. As you can see the channels are disabled in the OFDMA, but last time I checked one was enabled. Seems this issue is not consistent, but if you review the tables and give some feedback I'd really appreciate it. thanks,


Port IDFrequency (Hz)ModulationSignal strength (dBmV)Channel IDSignal noise ratio (dB)BytesCorrectedsUncorrectables
Downstream Overview
1375000000256QAM-2.799140.94622688480400
2381000000256QAM-2.500240.94622059972100
3387000000256QAM-3.000340.94622092248700
4393000000256QAM-3.500440.36622122865000
5399000000256QAM-2.700540.94622019377200
6405000000256QAM-3.099640.36621859801800
7411000000256QAM-4.200740.36621833915800
8417000000256QAM-3.200840.94621911449700
9603000000256QAM-7.099938.60522582157400
10609000000256QAM-7.0991038.98323413328300
11615000000256QAM-8.2991138.98321903371300
12621000000256QAM-8.2001238.60521763325300
13627000000256QAM-8.9001338.60522102956300
14633000000256QAM-9.2001438.60521714206800
15639000000256QAM-10.0001538.60521732105000
16645000000256QAM-9.2001638.60521532563300
17651000000256QAM-9.7001738.98321209162300
18657000000256QAM-8.5991838.60522920463600
19663000000256QAM-8.0001938.98323175727000
20669000000256QAM-8.2002038.60522849350100
21675000000256QAM-8.5992138.60522562254900
22681000000256QAM-8.9002238.98323401208300
23687000000256QAM-9.2002338.98322689266000
24693000000256QAM-9.7002437.636080
Reset FEC Counters
ReceiverFFT typeSubcarr 0 Frequency(Hz)PLC lockedNCP locked,MDC1 lockedPLC LocationOccupied BW(MHz)SubcarriersPLC power(dBmv)
OFDM Downstream Overview
04K695600000YESYESYES1504751 ~ 844.951840-14.200001
1NANANONONONA0 ~ 0NANA
Port IDFrequency (Hz)ModulationSignal strength (dBmV)Channel IDBandWidth
Upstream Overview
12345600064QAM44.52026400000
23676800064QAM45.52046400000
33011200064QAM45.52036400000
41840000064QAM43.76013200000
Channel Index,Statelin Digital AttDigital AttBW (sc's*fft)Report PowerReport Power1_6FFT Size
OFDM/OFDMA Overview
0DISABLED0.00000.00000.00000.00000.00002K
1DISABLED0.00000.00000.00000.00000.00002K
 

micahelriley

New Around Here
I should correct that it wasn't one of the OFDM/OFDMA channels that was enabled before, I was looking at a different table.
 

Datalink

Regular Contributor
The short story, you need a tech to inspect and possibly replace your external cable and its connectors.

The longer story .......

micahelriley signal levels.png


Very simply, you have a signal level problem. The chart shows the DOSCIS 3.0 signal levels, channels 1 to 24 from your data. That line should be a flat line at 0 dBmV, not dropping down to -10 dBmV. In your case, that data almost doesn't matter as the modem is running DOCSIS 3.1 on the downstream side and is most likely not using the DOCSIS 3.0 channels. That depends on whether or not the modem is running DOCSIS 3.1 on the downstream side, neglecting any DOCSIS 3.0 data, or possibly running in a hybrid mode, using both DOCSIS 3.0 and 3.1 data.

In your case, Eastlink has configured the DOCSIS 3.1 OFDM channel to start at 695.6 Mhz which is at the far right hand corner of that curve. The occupied bandwidth runs from 751 to approx 844.95 Mhz, even further to the right. So, at that point the signal levels are dropping off of a cliff. That would explain the poor downstream performance. Its possible that the modem is having a hard time processing the OFDM data, and might be switching back and forth between the DOCSIS 3.0 and 3.1 data. It all depends on the limits that Eastlink is using.

Food for thought, its typical on many ISP systems to see a high frequency roll off starting at 750 Mhz, which means that the signal levels drop even further at or above 750 Mhz. That's due to older equipment in place that isn't designed to support frequencies above 750 Mhz. That's a reflection of the design of the cable system to support analogue cable tv. To support higher frequencies, the output cards of the neighbourhood node, any amplifiers between the node and your modem, and the local tap have to be rated for higher frequencies. The local tap is located at the nearest utility pole, or in the case of underground cabling, inside the nearest pedestal, which should be visible from your front door. That tap looks like this:


You and your immediate neighbours will be connected to a local tap.

Given the higher frequency range of the DOCSIS 3.1 OFDM channel, Eastlink should have ensured that all of the cable system components in your local area support frequencies above 750 Mhz. If not, that high frequency roll off will be a problem for the OFDM channel.

Call Eastlink tech support and ask them to run a signal check on your modem. I'm assuming that they have an automated display that should simply indicate a pass/fail result. The result should indicate a failure. For the Hitron modem, there is a signal display available that breaks down the OFDM channel into 10 or 12 sub-bands. The might not be available to the front line techs, but you can always ask. If not, the only data that the tech sees will be a single line of data, just like what you see in the OFDM data line. The OFDM channel signal level might fail on two accounts, simply for low signal levels, and for an excessive downward slope if the signal level drops even further above 700 Mhz. There isn't enough data available to determine that, but, if the tech has an OFDM sub-band data display, that drop would show up on his or her data display. No matter what, given the signal data and the signal drop-outs that occur, the tech should agree that there's a problem that requires a field tech to check out.

The upstream frequencies run under 50 Mhz, which is on the left hand side of that chart. Those channels are a little high, normally their in a 36 to 40 dBmV range. If the tech solves the issue with the cabling and its connectors, I'd expect to see those signal levels drop into the 36 to 40 dBmV range. Where they are now isn't a problem, their just higher than I would normally expect, but, given the downstream signal issues, where they currently sit does make sense.
 
Last edited:

micahelriley

New Around Here
The Tech. was here earlier and completed a signal check. I mentioned we had a storm months ago where a tree fell on the lines and stressed the hell out of it. After testing and checking the cable/connectors he said it looks like water ingress in the cable. They're replacing the entire cable from the pole to the house next week. Funny part, or not so funny part is that I had a hard time convincing the Tech Support over the phone that there were issues, as all their tests showed passing results. As well, the speed tests online showed passing levels which made things more confusing. Maybe their pass/fail criteria is set beyond the limits as to what they should be, or perhaps they should know how to read the data tables, or ask the customer to read them the tables if they can't access them. Anyway, thank you for taking the time to respond and educate, you were right on the money with the cable!
 

Datalink

Regular Contributor
Fwiw, when the tech is around, running cable from the utility pole, ask him what the frequency range happens to be for the tap that's located up on the pole. It should be at least 5 to 1000 Mhz, considering that Eastlink is running a high OFDM channel that runs from 751 to approx 844.95 Mhz. If the tap is rated for 5 to 750 Mhz, then you're going to experiance a high frequency roll off due to the decreasing frequency response above 750 Mhz. Depending on how fast that roll off is, it might affect the OFDM channel performance. I'd say that there's a better than average chance of that occurring.

So, it would make sense to find out, just to know what to expect. The tech should be able to take one look at the tap when he's up on the utility pole replacing your cable, and tell you what the frequency response is. If the taps need replacing to accommodate higher frequencies, I'd expect any ISP these days to be replacing those taps as the opportunity presents itself.

Newer taps these days run from 5 Mhz to 1218 Mhz to allow high frequency OFDM channels. That upper range above 1000 Mhz is part of the newer DOCSIS 3.1 specs.
 
Last edited:

micahelriley

New Around Here
The Tech. actually came back to replace the cable, so unfortunately I can't ask, but if you think I should ask Eastlink I will. He also replaced an unused splitter in the basement that gained approx 3.5dB. Here's a look at the tables after the fix.


Port IDFrequency (Hz)ModulationSignal strength (dBmV)Channel IDSignal noise ratio (dB)BytesCorrectedsUncorrectables
Downstream Overview
1375000000256QAM5.400140.94647786902400
2381000000256QAM5.400240.36648359860900
3387000000256QAM5.400340.94649630493100
4393000000256QAM5.300440.94649190854600
5399000000256QAM5.300540.94650211266500
6405000000256QAM5.300643.37651469767100
7411000000256QAM5.099740.36651435218800
8417000000256QAM5.300840.94655607097500
9603000000256QAM4.800940.36656951984770
10609000000256QAM4.6991040.366567885502110
11615000000256QAM4.6991140.94653518513300
12621000000256QAM4.6991240.94653741636350
13627000000256QAM4.5001340.94653601648200
14633000000256QAM4.5991440.36652842121900
15639000000256QAM4.5991540.94653456987900
16645000000256QAM4.6991640.94652513115700
17651000000256QAM4.5001740.94653287406100
18657000000256QAM4.5991840.36656924763100
19663000000256QAM4.4001940.94658064873620
20669000000256QAM4.4002040.94658391307760
21675000000256QAM4.0992140.94659385920510
22681000000256QAM4.0992240.94659761350100
23687000000256QAM4.0002340.36660208150720
24693000000256QAM3.7002440.3660140
Reset FEC Counters
ReceiverFFT typeSubcarr 0 Frequency(Hz)PLC lockedNCP locked,MDC1 lockedPLC LocationOccupied BW(MHz)SubcarriersPLC power(dBmv)
OFDM Downstream Overview
04K695600000YESYESYES1504751 ~ 844.9518402.400002
1NANANONONONA0 ~ 0NANA
Port IDFrequency (Hz)ModulationSignal strength (dBmV)Channel IDBandWidth
Upstream Overview
12345600064QAM39.52026400000
23676800064QAM40.02046400000
33011200064QAM39.27036400000
41840000064QAM38.76013200000
Channel Index,Statelin Digital AttDigital AttBW (sc's*fft)Report PowerReport Power1_6FFT Size
OFDM/OFDMA Overview
0DISABLED0.00000.00000.00000.00000.00002K
1DISABLED0.00000.00000.00000.00000.00002K
 

Latest threads

Sign Up For SNBForums Daily Digest

Get an update of what's new every day delivered to your mailbox. Sign up here!
Top