# Cable Signal Strength Help



## kturcotte (Dec 9, 2002)

I think I'm having problems with my cable signal, or I'm going to down the road. Earlier this morning, they came and installed the cable card. The signal from the cable company was coming directly into the house, and split 2 ways, one to the Premiere and one to my cable modem. He measured everything, and it was excellent. Premiere was reporting 35dB and getting low 90's for signal. I was on satellite, but I found the PQ on the HD cable acceptable, so I converted the whole whose over to cable. Now the signal goes into a 4-way splitter, with one of those lines feeding another 4-way splitter which is feeding my Premiere, cable modem, and 2 digital cable boxes. Everything is working fine, but when I go into DVR Diagnostics, I'm getting a 31dB-32dB and a signal strength in the mid to high 50's. First, is that fine? Will that cause problems done that road? Thinking it would, before the second splitter, I added a preamp (Channel Master 7778) and fed the output from that into the splitter. The Premiere loved it. 37dB and low 90's for signal strength. The cable modem did not however. It absolutely refused to connect. The *ONLY* way I could get it to connect was the completely remove the amp from the setup, which is how I have it now. I even tried adding a couple of splitters before the modem, to kill some of the signal, and that didn't work. Is this going to be all right like this? If not, what can I do?


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## orangeboy (Apr 19, 2004)

If you can, isolate the run to the cable modem, and amp all the others?


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## kturcotte (Dec 9, 2002)

Is this something the cable company can/should fix at the pole? If not, what is a recommended amp for cable (Bi-Directional)?


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## drewdog (Feb 3, 2007)

This is the cable companies problem to fix. They have specs that they have to follow for acceptable signal to any digital device. Likewise with the modem service as well. An amp should never be needed for a location only split 4 way. Unless you're 500 ft. + from the tap outside. The digital channels they check with their meter really shouldn't read outside of +7db to -7db. Consider Zero perfect.


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## kturcotte (Dec 9, 2002)

drewdog said:


> This is the cable companies problem to fix. They have specs that they have to follow for acceptable signal to any digital device. Likewise with the modem service as well. An amp should never be needed for a location only split 4 way. Unless you're 500 ft. + from the tap outside. The digital channels they check with their meter really shouldn't read outside of +7db to -7db. Consider Zero perfect.


Well, split 4 ways and then split 4 ways again lol IF they can't/won't fix it, what do you guys think of the Channel Master 3414: http://www.crutchfield.com/p_6593414/Channel-Master-3414.html?search=channel+master+3414&ssi=0&tp=6341? Would that fix it, or be too much signal?


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## drewdog (Feb 3, 2007)

Without knowing what the signal levels are to start, there is no way of know how much it needs to change. I don't know how your cable provider handles these types of issues, but here they have to fix this stuff. Their policy is to home run all the outlets where you would not have a situation where 4 pieces of equipment are on one outlet. I'd just hate to see you spend you money where it sounds like they have some things to correct. 

Given that the Tivo preferred the amp you have and the modem wont work off it.... I'd say something needs looked at.


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## drewdog (Feb 3, 2007)

About the only thing you can do with a signal level meter is check the levels in your cable modem. You should be able to get them by typing 192.168.100.1 in your browser address bar. Look under signal or something like that. (all modems are different) and post you rx and tx (upstream and downstream) power level. Also, if it tells you post what frequency it's on.


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## orangeboy (Apr 19, 2004)

drewdog said:


> This is the cable companies problem to fix. They have specs that they have to follow for acceptable signal to any digital device...


I don't believe this is true. I think the requirement is an adequate signal at the point the signal enters the eaves. Beyond that, it is up to the occupant to distribute the signal to the outlets.

Edit: And of course I can't find any link or information to back that up...


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## drewdog (Feb 3, 2007)

I'm sure it's different wherever you live. Here, if a service call is ran, the signal must be brought to an acceptable level. The only instance where the customer is really ever charged is when the problem was caused by the customer. But, I'm sure that whole situation varies by company, local office, even individual technicians and their desire to actually do any work that day. 

And there's always the "Well, this Tivo is your box, if you had our dvr we'd fix it." BS Remind them it's THEIR cable card in the box!

I guess I was just being optimistic for this guy


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## kturcotte (Dec 9, 2002)

drewdog said:


> I'm sure it's different wherever you live. Here, if a service call is ran, the signal must be brought to an acceptable level. The only instance where the customer is really ever charged is when the problem was caused by the customer. But, I'm sure that whole situation varies by company, local office, even individual technicians and their desire to actually do any work that day.
> 
> And there's always the "Well, this Tivo is your box, if you had our dvr we'd fix it." BS Remind them it's THEIR cable card in the box!
> 
> I guess I was just being optimistic for this guy


"It's your Tivo" I'm ready for lol Okay, I DO own the cable modem, lol, but all the other cable boxes in the house are THEIRS. I've noticed the picture on them breaking up too.


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## hmm52 (Feb 25, 2008)

kturcotte said:


> Well, split 4 ways and then split 4 ways again lol IF they can't/won't fix it, what do you guys think of the Channel Master 3414: http://www.crutchfield.com/p_6593414/Channel-Master-3414.html?search=channel+master+3414&ssi=0&tp=6341? Would that fix it, or be too much signal?


FWIW I'd just rule out using a preamp or distribution amp altogether. They should never be needed unless you're living in Fontainbleu. The 4X4 then 4X4 splitter series is not good. After the main splitter, it's best to not have any more splitters before the modem or before the TiVo.

I believe it is the cableco's responsibility to deliver a good signal as far as the device, not just to eaves. But you're better off if you've got a decent cable layout in place.


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## andyf (Feb 23, 2000)

You're amplifier may be a one-way device. Need to make sure if the amp is in front of the cable modem, that it can pass traffic in both directions.


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## kturcotte (Dec 9, 2002)

hmm52 said:


> FWIW I'd just rule out using a preamp or distribution amp altogether. They should never be needed unless you're living in Fontainbleu. The 4X4 then 4X4 splitter series is not good. After the main splitter, it's best to not have any more splitters before the modem or before the TiVo.
> 
> I believe it is the cableco's responsibility to deliver a good signal as far as the device, not just to eaves. But you're better off if you've got a decent cable layout in place.


I've got to feed the Premiere, the cable modem, a 2nd HD DVR (I wouldn't use the thing lol) and 3 HD boxes (Non DVR). I'll try bypassing the 2nd splitter and running directly into the Premiere and see what I get.


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## hmm52 (Feb 25, 2008)

My primary splitter is 5 way. Verizon provided that along with rewiring the whole house (early adopter; take no chances on cabling errors). Splitters should be available up to 8 way and provided by any cable company, I think.

2nd HD DVR?? Sony?
3 HD Boxes (Non DVR)?? Zenith or LG DTV receivers?
just curious...


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## Eddief66 (Oct 24, 2009)

andyf said:


> You're amplifier may be a one-way device. Need to make sure if the amp is in front of the cable modem, that it can pass traffic in both directions.


Exactly. In order for an amplifier to work for the internet it has to be 2-way.

@kturcotte,
Neither of the amplifiers you mentioned say anything about working with a cable modem or if they're 2-way. Search for broadband or internet amplifier and you'll get plenty of results. BTW, for an amplifier to work best it should be installed right where the cable comes into your house.


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## orangeboy (Apr 19, 2004)

I've got one of these: http://www.pctinternational.com/_products/northamer/amplifiers/dropamps.html

A contractor for BrightHouse gave it to me to compensate for poor cabling in an apartment complex.


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## kturcotte (Dec 9, 2002)

hmm52 said:


> My primary splitter is 5 way. Verizon provided that along with rewiring the whole house (early adopter; take no chances on cabling errors). Splitters should be available up to 8 way and provided by any cable company, I think.
> 
> 2nd HD DVR?? Sony?
> 3 HD Boxes (Non DVR)?? Zenith or LG DTV receivers?
> just curious...


The other boxes are all Cisco (Cable).


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## hmm52 (Feb 25, 2008)

My house is still cabled for quite a few outlets but I'm using much fewer than I originally thought I would. Two cablecard TVs have their own direct connections to the main splitter (homerun), as well as direct connects to a main splitter near preamp for OTA. Other HDTV devices with their own direct shots also. Everything except the TiVos has since fallen by the wayside. For tuner, guide and recording the TiVos are simply preferable especially for my wife. Not to mention the ability to transfer recordings (CCI:0X02 excepted). So I have a lot more capacity and cable than I need.

BTW if you do install more cable, I don't think there's any point in quad shield as long as you don't have or don't watch any analog channels. Quad shield takes larger terminals which cableco techs don't have, in my limited experience.


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## kturcotte (Dec 9, 2002)

Okay, I 'm not sure what's going on. I disconnected the splitters, and did a DIRECT run to the Premiere. 36dB 84 signal but 120 RS uncorrected in 1 min. Just the FIRST splitter connected, and a direct run from that to the Premiere. 32dB 59 signal and 0 RS uncorrected after 5 mins.


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## ewilts (Feb 26, 2002)

I believe the best solution is to do the following:
1. Directly from the wall, go into a HIGH QUALITY 2-way splitter. One goes to the cable modem and one is reserved to TV signals. 

2. From that 1 TV output, add a decent signal booster - Comcast provided mine - and from the go to HIGH QUALITY splitters.

Not all splitters are created equally. When I had Comcast out working on my signal issues, the tech gladly gave me a handful with no questions asked. Comcast originally tried to charge me for the signal booster but when I phoned as soon as my bill arrived, they immediately gave me a credit. I've been happy ever since.


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## hmm52 (Feb 25, 2008)

Yes, you need to be sure you have a high quality splitter as your primary. Right now I think you've been recycling the splitters on hand.

84 isn't a terrible SS value, though not ideal. The 14.5 update may improve this as seems to have happened OTA Premiere. With Series 3's, I sometimes have a small number of RS Uncorrected, in the 100s dependent on channel. But they have accumulated only in the brief phase of locking signal. After that there is no further accumulation - cable and OTA the same. If that is all that's happening with yours, I wouldn't worry about it. You're not having display issues with 84 SS, are you?


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## andyf (Feb 23, 2000)

ewilts said:


> I believe the best solution is to do the following:
> 1. Directly from the wall, go into a HIGH QUALITY 2-way splitter. One goes to the cable modem and one is reserved to TV signals.
> 
> 2. From that 1 TV output, add a decent signal booster - Comcast provided mine - and from the go to HIGH QUALITY splitters.
> ...


That is exactly my setup. I split the signal coming into the house 2 ways. One is for the modem, the other has an amp on it for the rest of the house.


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## kturcotte (Dec 9, 2002)

I am having *SOME* pixelating and blocking and stuff. The splitters are Skywalker splitters 5-2300 Mhz (Originally used for satellite). Model SKY23304D http://www.skywalker.com/itemdisplay.aspx?item=8972 http://www.solidsignal.com/pview.asp?mc=03&p=SKY23304D&d=Skywalker-4way-Splitter-for-Offair-and-Satellite-signals-%28SKY23304D%29&c=Signal%20Splitters&sku=


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## vman41 (Jun 18, 2002)

I use my modem (Mot. SB5100) to measure signal strength via its built-in web server at 192.168.100.1. This gives you the actual power level as well as signal-to-noise ratio. In my office, where the modem normally sits, it currently measured -1 dB power level and 39 dB SNR. If I move it to the living room just before the splitter, it sees 3 dB and 38 dB respectively. Note that the SNR was marginally worse even with a 4 dB stronger signal (anything over 32 dB is more than adequate). These power levels are degraded due to the heat, they will go up quite a bit when it cools off at night.

The cable feeding my office is RG6 which runs to a 6dB tap near where the service enters the house in the basement. The tap's output goes to a 35 ft run of ancient (1970's vintage) RG59 that ends in a wall plate in my living room. Since the cable run lengths are close to the same, the observed power levels are consistent.

I'm finally upgrading to digital cable on Monday and the installer may want to do something about the RG59 since it has higher loss than RG6 as the frequency goes up (RoadRunner is using channels at 651 and 657 Mhz). I don't want to mess with the wall plate though since it's congested with cable, phone, and internet, but still don't want it bypassed either. I'll suggest connecting the existing RG6 directly to the grounding block and moving the tap to a spot where it turns towards the office that will only leave a a 5 foot section of RG59.


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## kturcotte (Dec 9, 2002)

This is what the modem is giving me (I have NO idea what most of it means lol):
Status
Comment
Acquire Downstream Channel 633000000 Hz	Locked
Connectivity State OK	Operational
Boot State OK	Operational
Security Enabled	BPI+


Downstream Channel


Lock Status Operational
Modulation 256QAM
Channel ID 1
Provisioned Rate 15360 kbps
Symbol Rate 41879.195 Ksym/sec
Downstream Power -12.0 dBmV
SNR 33.0 dB


Upstream Channel


Lock Status Operational
Modulation 16QAM
Channel ID 2
Provisioned Rate 1024 kbps
Symbol Rate 2560 Ksym/sec
Upstream Power 50.0 dBmV


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## hmm52 (Feb 25, 2008)

Take what I say with many grains of salt because I don't have a cable modem, don't have a Premiere - maybe different SS scaling than a Series 3, and I'm not an authority on any of this. But it appears your signal level is too low if -12.0dBmv at modem is a good indicator. -6.0 to +6.0dBmv is the right range at every device, 0 to 1.0 being ideal for a TiVo as I recall. The reading of 59 SS would be way low for the Series 3; tiling and pixelating, lack of signal lock, begin in the high 60s and deteriorate from there. The fact that you have no RS Uncorrected at 59 is odd. Keep in mind that the values _can_ vary much from channel to channel. If you don't have display/tuning problems at 59 SS, when do you have them?

With Series 3s, my values are typically 90-100 SS, 34-37 SNR, RS uncorrected 0 on all channels except those due to signal lock phases occasionally. Some OTAs are in the 80s and 70s SS but without issue. Was told signal at TiVo was 1.0dBmv the last time it was checked by tech but I have no way to check this myself. If your signal is in fact too low at entry point to the house, it's definitely the cable company's responsibility.

Good luck.


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## kturcotte (Dec 9, 2002)

I installed the Channel Master 3414 splitter/amplifier seen here: http://www.crutchfield.com/p_6593414/Channel-Master-3414.html?tp=6341.These are my readings now. Good/bad?
Tivo:
Low-mid 90's for signal strength 37.0 dB

Cable Box
Inbound Quality-1 0.0 dB mV 36.0dB
Inbound Quality-2 0.0 dV 36.0 dB
FDC RF Quality 4.0 dB mV 31 .0 dB
OOB Network RDC Power 45.0 db MV 
Modem: 
Status
Comment
Acquire Downstream Channel 633000000 Hz	Locked
Connectivity State OK	Operational
Boot State OK	Operational
Security Enabled	BPI+

Downstream Channel

Lock Status Operational
Modulation 256QAM
Channel ID 1
Provisioned Rate 15360 kbps
Symbol Rate 41879.195 Ksym/sec
Downstream Power 6.0 dBmV
SNR 38.0 dB

Upstream Channel

Lock Status Operational
Modulation 16QAM
Channel ID 2
Provisioned Rate 1024 kbps
Symbol Rate 2560 Ksym/sec
Upstream Power 49.0 dBmV


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## vman41 (Jun 18, 2002)

kturcotte said:


> I installed the Channel Master 3414 splitter/amplifier seen here: http://www.crutchfield.com/p_6593414/Channel-Master-3414.html?tp=6341.These are my readings now. Good/bad?


The readings look serviceable, but the lack of upstream amplification shows. 45 and 49 dB power levels are in range but on the high side.


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