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NoelSemple1@gmail.com
05-19-08, 02:40 PM
I would be eternally grateful if one of the experts here could give me
some advice.

We live in Toronto and have Roger's cable internet and tv. Both the
cable modem and the tv work perfectly when connected directly to the
wall. However, when I introduce a splitter and attempt to use them
simultaneously, the tv continues to work but the modem doesn't.

I've tried at least 5 different splitters, including a $50 monster
cable model, none works.

I know the best solution would be to call the provider. The problem
is that we have what I think of as "guilt-free free cable tv." We
phoned the provider and told them to cancel the cable tv while
continuing the internet service. They stopped charging us but never
cut off the tv, so we continue to use it. If I call them about the
problem above I think they'll notice that we're not paying for the tv
and cut it off.

Is there any type of splitter or amplifier which would let us use the
net and the tv simultaneously without calling the provider and going
back to paying for both?

Many thanks for your help!
-Noel

Agent_C
05-19-08, 04:15 PM
On Mon, 19 May 2008 11:40:14 -0700 (PDT), NoelSemple1@gmail.com wrote:

>Is there any type of splitter or amplifier which would let us use the
>net and the tv simultaneously without calling the provider and going
>back to paying for both?

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

A_C

Elmo P. Shagnasty
05-19-08, 04:52 PM
In article
<d54d799a-bcf8-455f-b1e8-9bf416d0cc94@l64g2000hse.googlegroups.com>,
NoelSemple1@gmail.com wrote:

> We live in Toronto and have Roger's cable internet and tv.

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

Bill M.
05-19-08, 08:07 PM
On Mon, 19 May 2008 16:52:31 -0400, "Elmo P. Shagnasty"
<elmop@nastydesigns.com> wrote:

>In article
><d54d799a-bcf8-455f-b1e8-9bf416d0cc94@l64g2000hse.googlegroups.com>,
> NoelSemple1@gmail.com wrote:
>
>> We live in Toronto and have Roger's cable internet and tv.
>
>Who's Roger? Your next door neighbor? Are you stealing Roger's cable?
>Or is he letting you share his cable?

LOL Funny :)

--
Bill

Timothy Daniels
05-20-08, 12:18 AM
<NoelSemple1@gmail.com> wrote:
> We live in Toronto and have Roger's cable internet and tv. Both the
> cable modem and the tv work perfectly when connected directly to the
> wall. However, when I introduce a splitter and attempt to use them
> simultaneously, the tv continues to work but the modem doesn't.
>
> I've tried at least 5 different splitters, including a $50 monster
> cable model, none works.
>
> [......]
>
> Is there any type of splitter or amplifier which would let us use the
> net and the tv simultaneously without calling the provider and going
> back to paying for both?


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*

Ed Nielsen
05-20-08, 12:02 PM
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
<http://192.168.100.1>?

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:
> <NoelSemple1@gmail.com> wrote:
>> We live in Toronto and have Roger's cable internet and tv. Both the
>> cable modem and the tv work perfectly when connected directly to the
>> wall. However, when I introduce a splitter and attempt to use them
>> simultaneously, the tv continues to work but the modem doesn't.
>>
>> I've tried at least 5 different splitters, including a $50 monster
>> cable model, none works.
>>
>> [......]
>>
>> Is there any type of splitter or amplifier which would let us use the
>> net and the tv simultaneously without calling the provider and going
>> back to paying for both?
>
>
> 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*
>
>

Agent_C
05-21-08, 02:02 PM
On Mon, 19 May 2008 11:40:14 -0700 (PDT), NoelSemple1@gmail.com wrote:

>Is there any type of splitter or amplifier which would let us use the
>net and the tv simultaneously without calling the provider and going
>back to paying for both?

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

A_C

NoelSemple1@gmail.com
05-21-08, 06:12 PM
On May 20, 12:18 am, "Timothy Daniels" <SpamBuc...@NoSpamPlease.biz>
wrote:
> <NoelSemp...@gmail.com> wrote:
> > We live in Toronto and have Roger's cable internet and tv. Both the
> > cable modem and the tv work perfectly when connected directly to the
> > wall. However, when I introduce a splitter and attempt to use them
> > simultaneously, the tv continues to work but the modem doesn't.
>
> > I've tried at least 5 different splitters, including a $50 monster
> > cable model, none works.
>
> > [......]
>
> > Is there any type of splitter or amplifier which would let us use the
> > net and the tv simultaneously without calling the provider and going
> > back to paying for both?
>
> 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*

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.

NoelSemple1@gmail.com
05-21-08, 06:15 PM
On May 20, 12:02 pm, Ed Nielsen <egn...@netscape.net> wrote:
> 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
> <http://192.168.100.1>?


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

Timothy Daniels
05-21-08, 07:44 PM
<NoelSemple1@gmail.com> wrote
> The problem occurs when I use the splitter with or without the tv
> connected, so I think I can rule out the interference hypothesis.

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*

$Bill
05-21-08, 07:44 PM
NoelSemple1@gmail.com wrote:
>
> 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?

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.

Todd H.
05-21-08, 09:28 PM
NoelSemple1@gmail.com writes:

> On May 20, 12:02 pm, Ed Nielsen <egn...@netscape.net> wrote:
>> 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
>> <http://192.168.100.1>?
>
>
> 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?

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?


--
Todd H.
http://www.toddh.net/

NoelSemple1@gmail.com
05-21-08, 10:17 PM
On May 21, 9:28 pm, comph...@toddh.net (Todd H.) wrote:
> NoelSemp...@gmail.com writes:
> > On May 20, 12:02 pm, Ed Nielsen <egn...@netscape.net> wrote:
> >> 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
> >> <http://192.168.100.1>?
>
> > 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?
>
> 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?
>
> --
> Todd H.http://www.toddh.net/

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 Iíve tried, I get no connection at all and
therefore cannot run tests.

If Timís analysis is correct, I guess I need a technician? (Iím
certainly not knowledgeable enough to answer Timís questions myself.)
Iíd love to call the provider and have them rewire it for free, but as
noted above I donít want my ďguilt-free free cable tvĒ 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.

Robert Nichols
05-22-08, 10:46 AM
In article <1d7bf9af-1749-4935-9b26-8921d8948df9@d1g2000hsg.googlegroups.com>,
<NoelSemple1@gmail.com> 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."

--
Bob Nichols AT comcast.net I am "RNichols42"

Timothy Daniels
05-22-08, 07:37 PM
"Todd H." wrote:
>
> That upstream power looks to be at the very edge of usability in my
> experience.


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*

Timothy Daniels
05-22-08, 07:42 PM
<NoelSemple1@gmail.com> wrote:
> 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 Iíve tried, I get no connection at all
> and therefore cannot run tests.

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*

Bill M.
05-22-08, 08:22 PM
On Thu, 22 May 2008 16:37:23 -0700, "Timothy Daniels"
<SpamBucket@NoSpamPlease.biz> wrote:

>"Todd H." wrote:
>>
>> That upstream power looks to be at the very edge of usability in my
>> experience.
>
>
> 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? <snip>

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.

--
Bill

NoelSemple1@gmail.com
05-22-08, 10:09 PM
On May 22, 8:22 pm, Bill M. <wbill...@hotmail.com> wrote:
> On Thu, 22 May 2008 16:37:23 -0700, "Timothy Daniels"
>
> <SpamBuc...@NoSpamPlease.biz> wrote:
> >"Todd H." wrote:
>
> >> That upstream power looks to be at the very edge of usability in my
> >> experience.
>
> > 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? <snip>
>
> 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.
>
> --
> Bill

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.

Todd H.
05-22-08, 10:34 PM
"Timothy Daniels" <SpamBucket@NoSpamPlease.biz> writes:

> "Todd H." wrote:
>>
>> That upstream power looks to be at the very edge of usability in my
>> experience.
>
>
> 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.

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.

> 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?

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 **** 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,
--
Todd H.
http://www.toddh.net/

Timothy Daniels
05-23-08, 12:22 AM
"Bill M." wrote:
> 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.

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

*TimDaniels*