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batsona
Maryland
join:2004-04-17
Ellicott City, MD

batsona to jasontaylor

Member

to jasontaylor

Re: [HD] Is Verizon lying about HD?

Sooo.. The limitation here is the RG6 coax connecting to the STB, where VZ is only utilizing 860Mhz (~810 usable) correct? Mathematically, that does limit the number of QAMs, as was seen in an earlier post.

Any Dish implementation uses RG6, and the signals come off that dish somewhere between 1,000 and 1,500Mhz, right? Plus... Any VZ installer makes sure that the coax cabling has good integrity anyway.. why not allow the use of ~1.5Ghz of space, instead of the current 860Mhz on that coax?

One reason is that they might not trust the integrity of that cabling, since attenuation increases with the higher frequency...
jasontaylor
join:2010-11-17
Kensington, MD

jasontaylor

Member

"why not allow the use of ~1.5Ghz of space, instead of the current 860Mhz on that coax?"

If there are 4 or more 4 tvs + 1 router, the signal might not be strong enough. Splitters aren't perfect, and they get worse above 1 ghz. A few db here, a few db there, and pretty soon, no signal. Each splitter halves signal strength, which is 3db. However, below 1ghz you can have 8 tvs.

Techygeek
@jillyred.net

Techygeek

Anon

Mister Taylor the reasons you give for verizon not going above 1ghz are incorrect. First of all when verizon launched fios, and even today there are no STB ,manufacturers making boxes with tuners above 860mhz. No cable company has boxes tuning above 860mhz. Only tunjng above 860mhz on fios boxes is moca (or mocha as u call it) which is in the 1.1ghz range. Fios signal strength out of the ONT can easily handle 8 sets in most situations and an amp is installed if signal strength is not enough for bigmhomes with long runs. Splitter loss is 3.5th not 3db and is closer to 4 or more DB on high ehd of the spectrum.

ITALIAN926
join:2003-08-16

ITALIAN926 to jasontaylor

Member

to jasontaylor
From Motorola...
»www.motorola.com/staticf ··· inal.pdf

For the newer 7232...

Video QAM 54 - 860Mhz
IP 1125Mhz - 1525

The old 2500 IP is 1125Mhz - 1425

I thought Moca ran between 860 and 1000?

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MVM
join:2005-09-26
Cape Coral, FL

More Fiber

MVM

said by ITALIAN926:

I thought Moca ran between 860 and 1000?

MOCA WAN is 1000 Mhz (975-1025).
MOCA LAN is 1150 Mhz (1125-1175).

ITALIAN926
join:2003-08-16

ITALIAN926

Member

So, the majority of splitters in the real world, and the ones primarily installed by Verizon are rated 5-1000Mhz, but the MOCA LAN works on 1150Mhz, interesting to know that the splitters will pass that.

landminer
@verizon.net

landminer

Anon

said by ITALIAN926:

So, the majority of splitters in the real world, and the ones primarily installed by Verizon are rated 5-1000Mhz, but the MOCA LAN works on 1150Mhz, interesting to know that the splitters will pass that.

verizons plan from the beginning was to use as much installed in home wiring as possible to cut down on installation cost, labor, and inconvenience to customer. that included the widely installed base of coax & 1000mhz splitters. those splitters are rated and guaranteed for 1000mhz but pass frequencies much higher. there is not a hard stop band @ 1000mhz however there is roll off which means more loss as you go higher above 1000mhz. MOCA was designed specifically with this in mind.
Expand your moderator at work

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MVM
join:2005-09-26
Cape Coral, FL

More Fiber to ITALIAN926

MVM

to ITALIAN926

Re: [HD] Is Verizon lying about HD?

said by ITALIAN926:

MOCA LAN works on 1150Mhz, interesting to know that the splitters will pass that.

Splitters don't stop passing higher frequencies just because they're only rated to a certain frequency. It just that the attenuation is higher above that frequency.

A 5-1000Mhz splitter is typically rated by the manufacturer to pass 5-1000Mhz with only 3.5db of loss. Loss as 1150Mhz might be 3.9db. Not within spec, but tolerable for MOCA. MOCA claims to be usable up to 50db of loss. I'm skeptical of that number, but keep in mind that MOCA must pass through every splitter between every endpoint on the coax network and those losses are cumulative (including losses on each of the coax segments).

DocDrew
How can I help?
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join:2009-01-28
SoCal
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3 edits

DocDrew to batsona

Premium Member

to batsona
said by batsona:

Sooo.. The limitation here is the RG6 coax connecting to the STB, where VZ is only utilizing 860Mhz (~810 usable) correct?

No coax isn't the limitation.

The limitation is trying to broadcast all the channels at the same time even if no one is watching them. Why fill the pipe with 400 channels when only 5 different ones are being watched in the home at any one time?

If Verizon switched to IPTV, like Google or AT&T, they have enough bandwidth for all the channels. Their equipment can handle it.

Coax can handle 5 Gbps of data using QAMs. HD channels at mpeg2 are 12-14 Mbps each. Google couldn't even handle 1/4 of the channels FIOS does if they broadcast them like FIOS. AT&T couldn't even handle the data of 1 QAM (38 Mbps) to every house.

And if you don't think FIOS is looking at IPTV what do you think TV Everywhere is?
batsona
Maryland
join:2004-04-17
Ellicott City, MD

batsona

Member

I wonder what the holdup is on IPTV then.. I bet Verizon is afraid about having to deal with QOS all the way out to the IP-enabled STB. you need a rock-steady stream in order to make IPTV look like classical TV-via-RF...