Cable modem not working with TV cable plugged in

Waste of $25 - take it back if you can. $5 should get a decent 1-2 bi-directional splitter.

Are you able to access the power levels on your modem web page ? If so, what are the readings with and without the TV on ?

What kind of TV is it ? Plasma by any chance ? How far from modem ?

I would think a decent 5-100 MHz 1-2 bi-directional splitter would work if you have good power levels to the bedroom, but normally you only want one splitter on the modem line and that would give you a second one (but it still works with the TV off, so I don't think it's a problem for you having two splitters power-wise). Your description would make one believe there was some sort of interaction between the modem and TV. What are the exact numbers on the 2GHz splitter ? Everything written on it - model, low to high numbers, name, manufacturer.

Hello!

Here is more details:

1.Modem config page is disabled so no info is available.

1. TV is a regular analog TV-set (2 year old 27" Sony) located about

8-10 feet from the modem. modem located about 2 feet from the wall/outlet

1. There is only one signal split (and splitter) on the cable line in my bedroom 2, the main line splits into 2 lines, one goes to the TVset the other to the modem.

Now here is an interesting thing (I wasn't clear enough in my first post). What makes me think it's a signal strength issue is that when I use either regular (for $5, 1GHz, RCA, no other info ) or monster (already returned) splitter, the modem is not working even with TV cable unplugged. It looks like (to me) that the signal after the split is too weak. I mean too weak for the modem since TV always works fine.

So I bought an amplified splitter

which I am also thinking about returning) and there is an improvement! Modem works fine with the splitter on the line (which I interpret as a stronger, amplified signal ) but under one condition: TV cable has to be unplugged. This suggests me that with TV cable on signal gets weaker (is that true?) and modem stops working.

My another choice would be a signal booster with very good reviews:

But I am getting a kind of tired of driving back and forth and returning items one by one. And I am not completely sure if it's only the signal strength what causes this weird behavior.

Thank you for your reply, problem still not solved! Luke

$Bill wrote:

Why ? What kind of modem ? Make, model.

So that gives a total of two splits (you always try to keep it to one). What make/model is the other splitter at house entry ? Maybe you should swap that one out.

I don't like splitters with no info on them. Did you Google the model for more info ? Intermodulation, Return Loss, Isolation, Insertion Loss, etc are all useful pieces of info.

What happens if you put a 75 ohm terminator in the TV leg ? They're real cheap.

It's Toshiba 2500/2600 sth. I am at work now, I can post detailed info when I'm back at home. I've read that many cable companies block that page (by firmware changes) so users don't try to hack modems.

You're right. But the very first split is hidden somewhere inside the walls thus not accessible to me /and I am just renting this apartment/.

Monster info was on manufacturer's web page. As for RCA splitter I didn't find anything. I'll try to buy one more today (a cheap one). But I did checked RCA splitter in my friend's apartment (similar setup, tv/internet split) and it worked fine.

Tried this with RadioShack splitter (it came with 3 terminators) and it didn't help.

I'll try to borrow another modem for a few hours tonight and check if that helps.

And what do you think about Motorola booster I mentioned previously? Looks like there are dozens satisfied users/owners...

Thanks again, Luke

I'm not an expert but in my experience a cable modem has to be on its own leg from the splitter. In other words, the incoming line from the street goes into a 2 way splitter and one leg of the splitter goes to the modem, the other leg to the tv(one or more). When I tried my modem in a different room it did not work as well. I concluded that it's a signal strength problem. I think you would need a really strong signal entering the house to allow the modem to be not the original split and still work well. What you probably could do is to replace the original

2 way splitter where the line first enters the hous with 3 way splitter--and connect the modem to the output leg with the lowest signal loss, and the two tv's to the other legs. If that doesn't work you could try putting the 2 way splitter back and put an amplifier where the line enters the house, before the 2 way splitter. This might let you split the stronger signal to the modem with the tv in the room.

Ken

Luke wrote:

Kenneth,

I understand but I can not make this kind of changes to the apartment I rent. I don't even know where to look for the first splitter! It may be somewhere in TW cable box as well.

And as I said the modem/Internet does work with 2 splitters for me (2nd splitter amplified). But as soon as I plug in tv cable to the amplified splitter the modem stops working. For the moment however (checked it this morning), they are both working! And then after 10-15 secs modem's cable led goes off.

As if there was a logical rule programmed in somewhere (in the modem?): disable Internet cable signal when tv cable plugged in/detected. Is that possible?

And one more thing: I would rate my bedroom 2 tv signal quality as good, not perfect but I am ok with that. I can see no difference between when I have tv with no splitter in my bedroom 2 and tv signal going through the splitter.

They (tv, internet) both work fine with 2 splitters - but separately. Just can not work together and I am trying to determine why.

Each splitter weakens the signal but this happens regardless of whether there is anything plugged in or not - at least I would think so.

Luke

Kenneth J. Harris wrote:

That would mean running another line to the bedroom. If he can do that, it would probably work fine. I was assuming he didn't want to or couldn't run another line.

It may not be blocked - it may be off by default. There may be some hacks available. The 2600 has to be enabled by ISP I hear - I have some help suggestions that were posted that you can try for the 2600 if you want.

The RCA worked for him or for you ? If you, with or without TV on it ?

No experience - maybe someone else has some first-hand experience.

How could I find it? Any thread name/date/website?

It worked fine in his apartment with internet and tv. But his signal might have been stronger... we don't know.

I just found 2 threads with similar problems:

people say about filters which prevent feedback signal from TV interfering with splitter/cable modem. That might be it... what do you think?

Thanks, Luke

Email me and I'll send what I found. It's all available via Google search. Do you have a 2500 or 2600 ?

Certainly worth a try if you can find one.

It's PCX2500.

I'll try to email you!

Luke

OK, much of that info was for the 2600 only I believe.

Don't forget to remove the SPAMOLA from the email addr.

It's a pity, I would still like to check my modem signals...

Yep, and here is the problem! I post messages via www (google [no spell checker]) and your full email address is not revealed. What I can see is snipped-for-privacy@SPAMOLAtodbe.com. Moreover, it's not editable so there is nothing I can do... At least not using www (my newsgroup client is not configured)

Anyways... a miracle happened tonight!!! My apartment experienced an unexplainable signal boost! TV picture quality on both lines is just incredibly sharp (as never before) and ... modem is working as I wanted it to be working with a regular splitter (RCA). No amplifier necessary! I am keeping my fingers (not cables :-) crossed and hopefully I will not have to come back to this thread and ask for help anymore.

But I still want to get to my modem config page so if you have any useful information on 2500 model I would try to email you anyway. Is it worth it?

Thanks a lot, Luke

just use news for the username: news (at) todbe.com

It's not obvious how much of the info is 2500 vs 2600. Email me and I'll send it all and you can try a few things.