Trying to split a cable signal ...

Yes, a Monster Cable TGHZ-2RF. Connect the cable modem to the "Power Pass" lead.

A_C

Who's Roger? Your next door neighbor? Are you stealing Roger's cable? Or is he letting you share his cable?

LOL Funny :)

A normal splitter should work. Is it possible that you used splitters made for satellite use? What is the passband for the splitters that you used? A normal splitter made for CATV and cable/internet would have a passband of 5MHz to 900MHz or 1,000MHz. BTW, anything made by Monster Cable is grossly overpriced and intended to suck money out of gullible people. A good splitter is cheap enough to be given away by the cable company. I once walked into the supply yard of the local cable company (now Time Warner) and asked for a splitter and offered to pay for it. A technician went to his truck and just gave me one and said to forget it.

There is also the possibility that you need a filter for the TV. It keeps the electrical noise from the TV from getting into the cable infrastructure of the cable company. Some older TVs can also make enough noise to interfere with the upstream internet signals. These you *might* be able to buy at Radio Shack, but more likely you'd have to get one from your cable company.

*TimDaniels*

Tim brings up a very good point about a diplexer. Make sure that the splitter used reads 5-1000MHz and not 5-860 on one leg and 950-2000+ on the other leg.

With just your cable modem connected, what are the signal levels (downstream and upstream, as well as S/N) as found at ?

Monster is getting to be sadly hilarious. Now, they are suing a miniature golf course in Rancho Cordova along with the Rhode Island woman who sells Monster Mini Golf franchises for trademark infringement.

CIAO!

Ed N.

Timothy Daniels wrote:

Yes, a Monster Cable TGHZ-2RF. Connect the cable modem to the "Power Pass" lead.

A_C

Many thanks Tim for your help. I have tried 2 splitters rated

5-1000 MhZ, plus the Monster which I agree was ludicrously overpriced even it had worked.

The problem occurs when I use the splitter with or without the tv connected, so I think I can rule out the interference hypothesis.

Thanks Ed! Here are my signals:

Downstream Value Frequency 615000000 Hz Signal To Noise Ratio 38.6 dB Power Level -1.0 dBmV The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading

Upstream Value Channel ID 4 Frequency 25296000 Hz Power 55.2 dBmV

how does this look to you?

thanks again,

-Noel

wrote

Hmmm... suspicion turns to the cable between the wall and the splitter. Who attached the connectors for that cable and what kind of connectors are they (e.g. hex crimp [boo], compression fit such as SnapNSeal, Digicon, SuperLok [yayy], push-on [superBoo])? Are the connectors sized to match the cable size? Is the cable shielded under the outer sheath with what looks like aluminum foil in addition to the metal braid?

*TimDaniels*

Your Tx power is on the top edge of acceptable at 55.2, Rx is a bit high, but well within bounds and your SNR is very high (which is good).

Is this with or without the splitter ? If it's without, you're gonna have problems when you put it back in. Put it back in and post the new numbers if so.

That upstream power looks to be at the very edge of usability in my experience.

If you ping -t google.com for about 30 seconds and hit ctrl-t what sort of packetloss are you seeing?

Thanks again everyone for all of your helpful advice!

The numbers posted above are without the splitter. Also without the splitter, 500 pings to google.com produced 0% packet loss. With any of the three splitters I=92ve tried, I get no connection at all and therefore cannot run tests.

If Tim=92s analysis is correct, I guess I need a technician? (I=92m certainly not knowledgeable enough to answer Tim=92s questions myself.) I=92d love to call the provider and have them rewire it for free, but as noted above I don=92t want my =93guilt-free free cable tv=94 axed.

Maybe I should hide the tv and just say that the signal is problematic in that the upstream power is too high? Then, hopefully, the Rogers tech will rewire and I will bring the tv back out from hiding and the modem and tv will live happily ever after together?

But if they ask why the excessive upstream power is bothering me, is any problem other than the inability to split the signal which I can complain about? Maybe I should just pay another technician to check the wiring.

Once again, much obliged for all your assistance.

In article , wrote: : :But if they ask why the excessive upstream power is bothering me, is :any problem other than the inability to split the signal which I can :complain about? Maybe I should just pay another technician to check :the wiring.

Just tell them, "Sometimes it works, sometimes it doesn't. And, even when it's working, my upstream power level is running right at the maximum my modem can put out."

That generally means that the modem is transmitting at such a high power because it can't "hear" the downstream packets well, doesn't it? IOW, there's some kind of attenuation of the down- stream signal. Is there a chance that the OP is using a tap, i.e. a directional coupler, as a splitter and he has the modem on the tapoff port of the coupler?

*TimDaniels*

Assuming that those really are splitters, suspicion turns to the cable that runs between the wall and the splitter, or between the splitter and the modem. Substitute other cables for those and run the test again.

*TimDaniels*

I thought the CMTS sends instructions to the modem to command it to increase or decrease its upstream power level on a continuous basis so that the upstream signal strength *at the CMTS* is within spec. If so, it would mean that upstream and downstream power levels are independent of each other.

Well the tech came and replaced all of the cables running from the alleyway to the house, which he said were obsolete. Somehow, this cut off the guilt-free free tv, so the splitter issue is moot. Thanks anyway for all of your help.

Actually it means the upstream signal is getting attenuated on its way to the headend to and the head end during training keeps saying "crank it up, can't hear you" until they arrive at 55dB.

Possible. But more likely, he may be using a n inexpensive splitter where a DC should be used. I haven't followed the whole thread, but really this shit is best left to the cable company to do. Consumers can't seem to easily/reasonably get their hands on the things needed to do it right: namely, directional couplers and high quality cable terminations, and in some cases amplifiers with a passive return are needed (but are a last resort, as they add noise which the cable modems hate even more than poor signal levels).

Best Regards,

Ooops, I think you're right. The CMTS is in charge.

*TimDaniels*