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Are these good modem signal values?

RolloTomasi
Regular Visitor

Are these good modem signal values?

Yesterday I upgraded my internet to 400Mbs down, and when I do a speedtest, the results are actually much lower than what I was getting before on my 200Mb plan.  I've rebooted my modem, and I plan to call and schedule a tech but was curious if these signal values are ok?

 

 

 

1LockedQAM25621483000000 Hz-10.8 dBmV38.1 dB6102789
2LockedQAM25617459000000 Hz-10.1 dBmV38.7 dB3245711
3LockedQAM25618465000000 Hz-10.0 dBmV38.7 dB3225922
4LockedQAM25619471000000 Hz-10.3 dBmV38.5 dB80311003
5LockedQAM25620477000000 Hz-10.5 dBmV38.2 dB8003753
6LockedQAM25622489000000 Hz-11.1 dBmV38.0 dB4532898
7LockedQAM25623495000000 Hz-11.0 dBmV37.8 dB28761169
8LockedQAM25624507000000 Hz-11.5 dBmV35.1 dB4092816
9LockedQAM25625513000000 Hz-12.0 dBmV37.2 dB1847670
10LockedQAM25626519000000 Hz-13.1 dBmV36.5 dB1855668
11LockedQAM25627525000000 Hz-12.6 dBmV36.7 dB1846737
12LockedQAM25628531000000 Hz-12.1 dBmV37.0 dB1836649
13LockedQAM25629537000000 Hz-11.9 dBmV37.1 dB3231750
14LockedQAM25630543000000 Hz-11.6 dBmV37.3 dB30881152
15LockedQAM25631555000000 Hz-12.0 dBmV36.9 dB1940660
16LockedQAM25632561000000 Hz-12.8 dBmV36.7 dB1945857

 

 
Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA45120 Ksym/sec35600000 Hz54.0 dBmV
2LockedATDMA55120 Ksym/sec29200000 Hz54.0 dBmV
3LockedATDMA65120 Ksym/sec22800000 Hz54.0 dBmV
4LockedATDMA75120 Ksym/sec16400000 Hz54.0 dBmV

 

EG
Expert

Re: Are these good modem signal values?

Both power levels are out of spec. And the SNR is low on some of the downstream channels is low. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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RolloTomasi
Regular Visitor

Re: Are these good modem signal values?

Thank you for the great advice.

 

There are currently 3 cables coming off the amp/splitter in the drop on the outside of the house...1 cable for each level of the house.  All the wiring is in the walls so I don't know if there are other spitters or not, but I've only found cable outlets in 3 rooms, so maybe no splitters exist???

 

The 3 cables going into the house from the drop go right into brick and then disappear in walls.  I will schedule a technician.

EG
Expert

Re: Are these good modem signal values?

If that actually is an amp / powered splitter on the line outside, ensure that it is powered on. If you do get a tech visit, good luck with it ! Please post back with how things turn out.



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RolloTomasi
Regular Visitor

Re: Are these good modem signal values?

Oh yes, the amp is powered.  If it isn't I get no internet service at all!!!  I ran the power myself.

RolloTomasi
Regular Visitor

Re: Are these good modem signal values?


@EG wrote:

If that actually is an amp / powered splitter on the line outside, ensure that it is powered on. If you do get a tech visit, good luck with it ! Please post back with how things turn out.


Hey one more question for you...the modem is connected to a wall jack that's on the complete opposite end of the house from where the drop is.  Could that distance affect the signal values?  Should I install an amp on the wall jack?

EG
Expert

Re: Are these good modem signal values?

O/k, fair enough.



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RolloTomasi
Regular Visitor

Re: Are these good modem signal values?


@EG wrote:

O/k, fair enough.


By chance did you see my other question above about the distance of the wall jack from the outside drop?

EG
Expert

Re: Are these good modem signal values?

Distance can affect / weaken the signals, but it shouldn't be that much. Perhaps there is an impairment with that cable run. Don't install any more amps ! I would let a tech investigate / decide what is needed.



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RolloTomasi
Regular Visitor

Re: Are these good modem signal values?

So tech came yesterday and made a ton of changes.

 

For starters he got rid of the commscope amp that was in the outside drop.  he said signals were good and that it's not longer needed. He said since 2015 when the drop / amp was installed, the signal from the head end has gotten much stronger and an amp no longer needed.

 

Then the signal on the new wall jack I was going to move my modem to was very noisy.  He swapped connectors to no avail, so we ended up running a new cable along the outside of the house and into the wall...and problem solved.  modem levels are now good.

EG
Expert

Re: Are these good modem signal values?


@RolloTomasi wrote:

  modem levels are now good.


For curiosity, can you post what they look like now please ?



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