signal strenght problem with adelphia?

I had the exact same problem on Comcast before I replaced the SB5100 with a Linksys BEFCMU10 (V3) -Dave

You are so full of shit, Warren. I was watching the signal strengths on the SB5100 when the problem was present, and when it was not. There was no change. There was no line problem. There was no problem that a line tech could solve, unless he brought a new modem with him. The problem disappeared at the exact time that the modem was replaced. I don't know if the OP has a bad modem, but *I* sure as heck did. -Dave

Well if you won't listen to logic, I guess I'd have to conclude that you're a moron. I know what the symptoms suggested. I also know what fixed the problem. For you to argue at this point makes you look like exactly what you are. -Dave

All the clues are there that there is a line problem. I could be as close as a splitter inside your house, or as far away as where the coaxial RF part of the network meets the fiber-optic part of the network (which could be miles from your house).

I don't know if Adelphia still uses different techs for "data" than for other problems, but ask the tech if he's a data tech there to fix your computer, or if he's there to fix the signal problems. If he's a data tech, make sure he understands that you are having a signal problem, and he needs to get someone out to address that.

Oh, and ignore the guy who is saying your problem will go away if you buy a new modem. He doesn't know what he's talking about.

If you did have the "exact same problem", then it was solved by Comcast line techs, and it was pure coincidence that you happened to buy a new modem at the same time.

I would say yes.

Downstream Receive Power: avg -15 to +15 (-10 to 0 preferred) Upstream Transmit Power: -8 to +58 (+25 to +55 preferred) SNR: 30 to 37 (>= 35 preferred)

For receive: The closer to the center of the spec, the better. For transmit (or output power), modems above 55 dBmV may experience random disconnects.

Buy some RG-6 or RG-11 and tie it on the end of your RG-59 and pull it back through your walls (unless you can get the tech to do it for you).

What does you cabling look like ? Splitters/type/model which leg are they connected to, etc ?

Start at the point where the cable arrives at/near the house.

Incoming line -->terminal block (grounded) --> 2-way splitter (5-1000MHz, 75 Ohm Imp.) | | | | | | V V Cable modem TV ?

etc.

This is turning into a story of the boy who cried wolf. I guess if you suggest replacing modem X with a Linksys BEFCMU10 (V3) often enough, one of these times you're bound to hit on a situation where it will be the right thing to do. Unfortunately, as is usually the case, this is not one of those situations.

Dave, if you remember, I was not the only one who told you that the symptoms you described were not those of a modem problem. YOU presented the set of facts that everyone else agreed indicated that it was NOT a modem problem. Then you tried to spin them, but no matter how much you spun, the FACTS still indicated it was NOT a modem problem, and everyone told you so. Repeatedly.

I don't know if you still believe that if you say something often enough it becomes true. But no matter how resolved you are, you were, and are, still wrong. And it's not just me who said so. The facts that YOU presented simply were not those of a modem problem, no matter how often you claim otherwise.

Now you can continue to spin all you want, but you're still not going to get anyone to agree with you that you had a modem problem unless you make-up new facts that contradict what you originally presented.

It's becoming tiresome that your solution to every problem is to buy a Linksys modem. Looking back at the entirety of your contributions here, it's starting to look like you're just a shill for Linksys. The only thing that doesn't make sense is that one would expect a shill for a technology company to actually have some technical abilities. You don't. Your constant solution to everything is buying a Linksys modem does not contribute to this group.

I'm sure there must be something you have some worthwhile knowledge about. Go find a newsgroup on that topic, and stop trying to pretend that you know a damn thing about the topics discussed here.

I know what the symptoms suggested, as did the others. You wanted the symptoms to suggest something else. I, and a number of others tried to no avail to show you how your desired outcome was not what logically followed the facts you presented. You rejected logic entirely.

You don't have any idea what fixed the problem. You only know what actions you took at the time the problem was resolved. However there was never any logical reason to believe that your actions were the cause of the resolution. Logic, as was pointed out to you, was that the problem was fixed by the cable company. But you rejected logic.

When talking about people who reject logic, Dave, you are the champion here.

As a further update, my service finally came back on by itself seemingly out of the blue. So, when the technician comes it won't be down for him to troubleshoot. However, I did save a screen print of the cable modem's signal strength page as I mentioned in my previous post from how it was behaving in the down time.

Now that its back on, I can go back in the signal page of the modem and see some big differences.

For downstream when the modem is synched and working, the signal to noise ration is on 38db. The downstream powerlevel shows as 0db.

For upstream, the powerlevel reads 51 dbm v and does not go below 50. This number doesn't have the wild fluctuations like it did during the outage. What does that indicate? Seems like it has to be something with the signal.

Also, do the power level readings have anything to do with the ac power that the modem is plugged into? If so, could a bad surge strip cause the wild readings? Or is the power level term with cable modems just applicable to signal characteristics?

Thanks for the help!!

Drew

Hi Robert:

Thanks for your help.

When its working , the upstream power level stays on 51 dbm almost constantly. If I set and refresh the cable modem signal page many times within a minute it will ocassionally go to 50 instead of 51. But when working, it never seems to move below 50 or above 51.

I'm going to print your email to show to the technician. None of them have said anything about realizing the upstream level is near its limit.

They have only been when its working so far and all they do is plug the coax into their meter and say signal looks good, there's nothing else to check!

So, maybe this will help.

Thanks man! Drew

In article , Drew wrote: : :As a further update, my service finally came back on by itself :seemingly out of the blue. So, when the technician comes it won't be :down for him to troubleshoot. However, I did save a screen print of :the cable modem's signal strength page as I mentioned in my previous :post from how it was behaving in the down time. : :Now that its back on, I can go back in the signal page of the modem :and see some big differences. : :For downstream when the modem is synched and working, the signal to :noise ration is on 38db. The downstream powerlevel shows as 0db. : :For upstream, the powerlevel reads 51 dbm v and does not go below 50. :This number doesn't have the wild fluctuations like it did during the :outage. What does that indicate? Seems like it has to be something :with the signal. : :Also, do the power level readings have anything to do with the ac :power that the modem is plugged into? If so, could a bad surge strip :cause the wild readings? Or is the power level term with cable :modems just applicable to signal characteristics?

How _high_ does the upstream power level get when the modem is working? That +51dbmv is a very high upstream power level. Your modem is having to transmit at near its maximum level of +58dbmv in order to make itself heard. If the losses in the cable system rise by just a few db, your modem won't be able to transmit a satisfactory level to the head end and you'll see the failure symptoms you describe.

In your case, it would be best if the technician came out while the modem *is* working. Any competent data technician should recognize the upstream level near its upper limit, and that's a more concrete symptom than just "modem can't sync."

BTW, the reason that the upstream level fluctuates wildly during the outage is that your modem is trying different upstream channels in an attempt to get a connection, starting each channel at a low transmit power and gradually increasing to the maximum, then moving on to the next upstream channel.

Mine's always in the 50-53 range and my SNR is a bit low, but it works fine (Terayon TJ715 rental). Today's numbers :

RF Parameters Parameter Value Units Tx Power 52.2 dBmV Rx Power -6.7 dBmV Downstream SNR 31.8 dB Tx Frequency 33000000 Hz Rx Frequency 705000000 Hz

Yeah, its almost a constant 51 when its working.

The apartments I live in were built in 1985 and the landlord says they have the old RG58 cable running thru them.

There is some kind of box behind the apartments that has a coax line for each apartment connected to a jack. I'm guessing this is the thing that connects the cable from the pole to run into the apartments.

Just as a test, should I have the technician just run a RG6 cable from this point thru a window or open door directly to the room where my cable modem is and then look at the signal levels again.

Or is it even possible that its the cabling inside of my apartment? It seems like if that were it that the problem would be more consistant.

I did do some googling on upstream power levels. Lots of forums and posts indicated that a upstream power level in the 50s was just too high and should be lowered by the cable company.

I understand the cause of the problem now. It sounds like something happens that makes the cable modem unable to send a signal back to the head end at its highest power level (58). Could this maybe be indicative of a bad amplifier in the neighborhood or something?

I just have a feeling that Adelphia is going to be unwilling to chase the problem. And I don't have much confidence in the techs that have visited so far. Nice guys but they just don't seem to have a thorough knowledge of what's going on.

Maybe something good will happen tomorrow when he visits. Should I still point out the higher end upstream power to him?

Thanks! Drew

In article , Drew wrote: :Hi Robert: : :Thanks for your help. : :When its working , the upstream power level stays on 51 dbm almost :constantly. If I set and refresh the cable modem signal page many :times within a minute it will ocassionally go to 50 instead of 51. :But when working, it never seems to move below 50 or above 51. : :I'm going to print your email to show to the technician. None of them :have said anything about realizing the upstream level is near its :limit. : :They have only been when its working so far and all they do is plug :the coax into their meter and say signal looks good, there's nothing :else to check!

If the level is pretty steady around +51dbmv that shouldn't be a problem. It's quite high, but still within the acceptable range. I was hoping you would see quite a bit of fluctuation, indicating an upstream signal path problem which, if it got much worse, would cause loss of communication. Sounds like you don't have that.

In article , Drew wrote: : :Yeah, its almost a constant 51 when its working. : :The apartments I live in were built in 1985 and the landlord says they :have the old RG58 cable running thru them. : :There is some kind of box behind the apartments that has a coax line :for each apartment connected to a jack. I'm guessing this is the :thing that connects the cable from the pole to run into the :apartments. : :Just as a test, should I have the technician just run a RG6 cable from :this point thru a window or open door directly to the room where my :cable modem is and then look at the signal levels again. : :Or is it even possible that its the cabling inside of my apartment? :It seems like if that were it that the problem would be more :consistant. : :I did do some googling on upstream power levels. Lots of forums and :posts indicated that a upstream power level in the 50s was just too :high and should be lowered by the cable company. : :I understand the cause of the problem now. It sounds like something :happens that makes the cable modem unable to send a signal back to the :head end at its highest power level (58). Could this maybe be :indicative of a bad amplifier in the neighborhood or something? : :I just have a feeling that Adelphia is going to be unwilling to chase :the problem. And I don't have much confidence in the techs that have :visited so far. Nice guys but they just don't seem to have a thorough :knowledge of what's going on. : :Maybe something good will happen tomorrow when he visits. Should I :still point out the higher end upstream power to him?

It's unlikely that the RG58 cable is at fault. The upstream channels are at the low end of the frequency spectrum (below 50 MHz). It's pretty unlikely that the cable would be satisfactory for the downstream channel (300 MHz to 1 GHz, typically around 700 MHz) but unable to pass the low frequency upstream channel.

A bad amplifier is certainly a possibility. That's going to be hard to pin down unless the technician can check while it is failing. There is also the possibility of some interfering signal at the upstream frequency being injected into the cable system, but that should affect a lot more users and be easily detectable by the cable company. And of course this could jut be an intermittent problem in your modem

Yes, I'd point out the high upstream level as a possible warning sign. Hey, even if that's not the root cause, correcting it could also fix the real problem.

Thanks :)

An an update, when the cable technician made the most recent service call, I suggested that we run a cable straight from the cable drop box behind the apartment directly into the room where my computer is. So, this is where cable comes into my apartment now. Previously, it first came into another room and then into the computer room via two splitters.

Now the cable comes straight into my apartment in the computer room. It runs right into a 3 way splitter (Adelphia splitter that they like to be used.). One leg for the cable modem, one leg for my computer's tv card, and then another leg for cable out to the rest of the apartment.

With this configuartion the upstream power level changed. Now instead of 51-53, it is reading consistently at 49-50. No downtime as of yet but I'm going to wait a bit longer to see if the problem occurs as it was not an all the time thing to begin with.

With this new configuration, the possibility of bad RG58 cable in the apartment has been eliminated as the new cable line the tech installed comes right into the computer room bypassing the cable put in when the apartments were built.

Is this upstream power dropping a significant improvement? Maybe this has it fixed.

Also, while the tech was there, I explained to him how many of my channels just look really grainy when watching TV. A couple of the channels, like 8 (FOX in my area) will have white specks dancing all across the picture. Its not overly distracting but still, its there. I've sort of got used to it I guess. Just to eliminate the possibility of bad cabling in the apartment, we ran a new line of coax straight from the splitter in the computer room to the TV in the living room so that the old RG58 cable was bypassed in the walls. We just laid it across the floor and hooked it up to test. The picture quality didn't change at all and the tech said, "Yeah, there shouldn't be graininness in the picture like that but the problem isn't in your apartment." All the signal levels are fine and we eliminated the RG58 cable as a potential problem.

He said thiis could be related to my signal dropping out. He said there was really nothing else that he could check. I asked if it was possible that there was a problem with some equipment between the cable office and my apartment. He said that he couldn't think of anything else to explain the picture quality and dropping Internet signals. He then went on to say that it would be very difficult for them to pursue the problem any further and that the management at the local Adelphia would probably not go any further. He then suggested that I move! LOL...should have saw that coming. After I said, "That's nuts, I shouldn't have to move to get a good picture.", the tech then said that I should consider upgrading to digital cable and that would make the signal a lot better.

Is that true? It looks to me like if there were problems in picture quality with analog cable that digital cable would have problems too. Sounded sort of like a rehearsed answer to me!

So, if it happens again, it looks like I'll be moving back to the trusty Sprint DSL service. I had it for a long time and never had any problems with it. It sounds like Adelphia isn't willing to chase the problem any further.

Thanks! Drew

"Digital cable" *sounds* like it would be a lot better quality than "analog cable", but it ain't necessarily so. It it's not going to change channel 8.

Essentially you have a whole spectrum of radio frequency (RF) signals coming through the cable. It's divided into RF channels. Good old fashion analog cable has one station you can watch on each channel matching the same channels on old TV's (up to a certain point), with more such stations you can view using a "cable ready TV."

With digital cable, you still have all of what you have on analog cable. But additional RF channels - beyond what even a "cable ready" TV set can receive - are used. The stations carried on those channels are digitally compressed, and multiple stations are carried on each channel. No longer is the mapping on station per channel.

You might compare the situation to photos on a computer. Analog would be like a BMP, and digital would be like a JPG. The BMP is limited by the format. The final picture takes up a lot of data space, but it is what it is. But if you save it as a JPG, it's digitally compressed. More JPG's fit in the same space the BMP fit, but depending on how far you compress it, some data may be lost.

But none of that is going to make the analog picture better on channel

8 -- unless they duplicate all the analog channels as digital channels, too, which under normal conditions probably wouldn't happen. Why waste even a compressed spot on the digital channels just to duplicate something that's already there in the analog channels? But this might be the case if channel 8 also has an HD version, if that HD version is available on one of the digital channels, if you get HD digital cable, and if you have an HD TV. That's a lot of if's.

Is the only problem on channel 8? Do other channels have problems, too? Do others in your complex have the same problems?

The wider-spread these problems are, the more willing they'll be to tracking it down and fixing it. Imagine the tenants of every apartment in the complex calling to complain about spots on channel 8. The folks in the call center may not notice a pattern as they schedule truck rolls for everyone, but when the field operations realize that they're spending half their resources on truck rolls to a single apartment complex, they're going to find a way to fix the big problem, rather than look at it as a bunch of small problems. Especially if people call back on a regular basis if the problem isn't solved.

On the other hand, if this isn't a problem shared by your neighbors, then we're not talking about a big problem, either. But despite how much has already been done to track down the problem, perhaps a new set of eyes on a new day may find the problem. Another call, and another single truck roll may be all that's needed to track down the problem, and fix it.

Don't settle until it's fixed.

Also keep in mind that if the problem is affecting TV reception, the local franchising authority can get involved officially. (If it's only affecting the Internet service, they may still be willing to get involved, but they won't have the same official leverage they have for TV issues.)

Hopefully it won't turn into a battle that big. And the next time a cable company employee suggests that moving may be the solution, suggest that dropping the service, and getting DSL and satellite TV may be the solution. And if that's not practical where you are, and you do have to move, that once you move it'll be to somewhere that DSL and satellite are practical solutions. You don't have to be their customer. They don't have a monopoly on anything that they bring into your apartment. They can be replaced.

Thanks Warren:

I only know one other person well in the apartments and see he doesn't have any cable problems like what I've described. I'm going to ask some of my other neighbors and get some feedback on that.

It so weird. I was noticing it again last night when I was watching Despearte Housewives and Boston Legal. These are channel 10 (ABC affiliate) in my area, so the problem isn't just limied to a single channel.

When someone was on screen in the shows and the background behind them was not a lighter color, you could see like a perfect silohette type thing of them repeated just beside the actual image. The picture was also grainy but the "ghost" problem was much more noticeable. Also noticeable is the station logo that many stations leave down in the corner or at least have their when a commercial is returned from. You could see a shadow of the TV14 or whatever thing perfectly. Very irritating.

And I can usually see ghosts on Monday Night Football which especially gets on my nerves!

Is there anything in particular that can cause the ghosting or grainy effect?

Thanks! Drew