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zedsdead
Premium
join:2000-08-24
Burlington, ON
reply to HiVolt

Re: CH 88 on Rogers Cable

That's a spectrum analyser for the return path for a certain node, more than likely for the node your on. The big spikes towards the middle are modems transmitting on that node. Looks like a pretty noisy return path though. Some headend techs like to set these up on a high channel so techs in the field can see what the noise floor etc. looks like.



shaner
Premium
join:2000-10-04
Calgary, AB

Just being a smartass, but do you get to charge them for using your TV for tech support?
--
I got my Sympatico HSE in a London box. Where did yours come from?



HiVolt
Premium
join:2000-12-28
Toronto, ON
kudos:21
Reviews:
·TekSavvy DSL
·TekSavvy Cable
reply to zedsdead

So the spikes are transmissons? or just general modem activity? Could one graph be for transmit, the other receive activity on the node? and this one steady graph, i wonder what that's for...
--
Crunch for Team Discovery!
Also visit www.ihaterogers.ca



DKS
Damn Kidney Stones
Premium,ExMod 2002
join:2001-03-22
Owen Sound, ON
kudos:2
reply to zedsdead

Nothing on our channel 88 in Owen Sound.
--
Bell HSE user by default...



zedsdead
Premium
join:2000-08-24
Burlington, ON
reply to HiVolt

The large spikes to the middle of the graph are modems transmitting back to the headend. The graph is from 5mhz to 42mhz (docsis specified return path) and reads from left to right. As you can see the lower the frequency (more towards the left) the more noisy it gets, which is normal to a point. However looking at the overall noise floor it looks high, that node probably wouldn't pass a DQM. Of course these are just my observations looking at a still picture Hard to say for sure without looking right at the analyzer.



zedsdead
Premium
join:2000-08-24
Burlington, ON

reply to DKS

Not all cable companies put these out on the system. We (Cogeco) to my knowledge do not. At least I've never seen or heard of us doing it. However in the office I work in we have the capability to look at analyzers in some of our systems remotely for monitoring purposes. Every headend definetly has an analyzer to look at the nodes that are served from it.
[text was edited by author 2002-07-28 21:18:28]

[text was edited by author 2002-07-28 21:20:04]