TeeVee over Fibre

Oh learned s.c.d; the source spring of all knowledege; I humbly request a very small smidgen of your wisdom.....

TV over fibre -- No, not the stuph Verizontal sells....

I have a friend & client building a log cabin in the woods. (To set the scale, the [indoor] pool is 80Kgallons.)

It's 1200 ft to where the solar array and satellite dishes will be. My question is: who if anyone makes the electronics needed to convert to glass for both video down and any data back up?

I have as little to do with TV, much less satellite TV, as possible; I assume you can use one dish on multiple receivers, which implies the feed from the dish is at some IF but is broadband of many megahertz.

(The alternative is the channel selection takes place at the dish; which would one channel at a time. I understand that's how SBC's U-verse is set up; the settopbox actually sends channel commands back to the 29-B coffin..)

I welcome enlightenment.

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A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
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Reply to
David Lesher
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You can make it fiber if you convert everything to a network stream at the feed end and back to video/data/all else on the receive side. Essentially placing a server at the signal source, and use a media server in the home to pull streams from it.

Use 10GbE or 100GbE over fiber.

There will be no inexpensive method to pipe the streams you want, the way you want. I just hope you know that.

Reply to
Copacetic

There is no advantage in fiber for a direct connection this short.

Reply to
Sjouke Burry

So price is no problem ?

Cable-TV companies have used a variety of high linearity transmitters to transfer something like 0-800 MHz across a single fiber. Using separate receivers for each sub-band and polarization on using WDM for each satellite / subband / polarization would allow all visible satellites down the same fibre.

If the cabin has less than a dozen receivers, this would definitively be the simplest option (provided that there are no extreme temperature requirements at the head end). 1 GbE fiber should easily do the job.

Reply to
Paul Keinanen

Co-ax is fine for that distance; why do you assume fiber?

The LNB, (Low Noise Broadband), amplifier, at the dish converts the K-band signals to an IF frequency in the 50 MHz-2000 MHz band which is then sent to the receiver(s), where the desired channel is picked out.

More than one dish, or a dish with multiple feeds may be required as some TV satellite systems use more than one satellite. An additional amplifier will be needed to drive 1200 feet of coax, but these are readily available. Many apartment buildings have co-ax runs >1200'.

For wide-band net operation via satellite the system is entirely different, but co-ax would be adequate here as well. Depending on the bandwidth required, the data could be di-plexed on the same co-ax or on a separate run.

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VWWall, P.E.
Reply to
VWWall

Why not use Airflex or Ecoflex coax if you are worried about attenuation, then equalize at the amp? Should be cheaper than fiber and less hassle. For the data link I can't imagine that needing more than

1200bd so CAT5 should work. But you may have to splice that since ordinary spools only contain 1000ft.
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Regards, Joerg

http://www.analogconsultants.com/
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Reply to
Joerg

The first thing I would worry about is the lightning protection at such distances.

For a single microwave head for a single polarization generates signals in the 0-2000 MHz range, which would require some intermediate amplifiers, trying to run two polarizations and multiple satellites through a coaxial cable, would require amplifiers every few meters.

Using WDM, there is no problem of handling multiple orbital positions and two polarizations on a single mode fiber.

Reply to
Paul Keinanen

Really from 0 MHz? That would be an inconvenience, else you can place baluns to isolate.

While FO to coax converters are ubiquitous the converters from coax to FO are probably expensive.

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Regards, Joerg

http://www.analogconsultants.com/
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Reply to
Joerg

No, I don't know that. Lots of video is run over fiber in many forms. [Belden just bought one company that does that at sporting events...] When I last looked at broadband video over fiber 15+ years ago, it was doable but pricy. Now, I don't know that's even still true.

True, if we turn it unto TCP/IP at the head end; it's straightforward, but that will need MythTV or similar at each set. I'm aware of an ASTV tuner with internal web server that does that encoding, but is the Satellite TV system feed really ATSC, QAM, or something else?

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A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
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Reply to
David Lesher

Give the man a prize. That's the first reason why I'm big on fiber here. We'll have multiple strands between the two locations as well as the 4160 vac. We can dedicate what's needed to this.

I'm also concerned re: duct space and the hassle of that long run of coax. ISTM some systems require multiple coaxes to the dish as well.

Not sure if they'll need >1 bird, but there shall be multiple sets; he'll have [by then...] teenage daughters....

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A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
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Reply to
David Lesher

On a sunny day (Mon, 12 Apr 2010 22:32:23 +0000 (UTC)) it happened David Lesher wrote in : , but is the Satellite TV system feed

The LNB is simply a down mixer. So the transmission system is not changed, just the frequency.

Reply to
Jan Panteltje

Doesn't look like it:

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Quote "Very few teleports outside the US support the ATSC satellite transmission standard, but teleport support for the standard is improving. The ATSC satellite transmission system is not used for direct-broadcast satellite systems; in North America these have long used either DVB-S (in standard or modified form) or a proprietary system such as DSS or DigiCipher 2."

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Regards, Joerg

http://www.analogconsultants.com/
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Reply to
Joerg

It looks like 200' is the max for unamplified LNB cable runs. Even with low loss cable and amps mid way, it still may not work well. Then you need to power the amps, etc. But, someone does make LNB-Fiber links He should call them to see if it will work in a consumer application.

Cheers

Reply to
Martin Riddle

IIRC Ecoflex is around 11-12dB per 100m at a GHz, so you'd lose 40-50dB over this run. Doesn't sound so terrible if amplified and equalized correctly. Amps can't be that expensive, for regular UHF I've got several in the basement here to drive coax runs.

Sez reasonable pricing, whatever that means :-)

But if the guy has a 80,000 gallon indoor pool it'll all be chump change.

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Regards, Joerg

http://www.analogconsultants.com/
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Reply to
Joerg

And you think those systems are cheap?

Jeez. Wake up. That term I gave was 10GbE, not ONE.

Reply to
Copacetic

I have an Acer Aspire Revo "nettop" computer that was $200. It is running "XBMC" (X Box Media Server). That runs under windows or Linux, and is what most folks are using for media these days, not MythTV.

You should do it as a net stream as that is where things are heading. Even Satellite access is moving toward streaming digital data or files over a network hook than tuning individual "TV channels".

Watch for satellite to make a comeback in the form of a network provider, not a "TV channel" programming provider. There are bi-directional systems already in place, no need for phone like the old Hughes system was.

Reply to
Copacetic

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Mark

Reply to
Mark

But that leave me with my isolation concern.

$1200 and up...

If he spends all his money on this stuff; there will be no pool..

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A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
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Reply to
David Lesher

Still a reach for teenage daughters....

But a Silicon Dust HDHome tuner will bring the DRM/decoding issue into play.

At present, that's what he can get for net access. But no one likes such; just tolerates it....

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A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
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Reply to
David Lesher

Not exactly 0 MHz, since any signal appearing at the image frequency would also get through any front end filtering. Even without any significant signal sources at the image frequency, the first preamp noise falling on the image frequency will also be mixed down to the intermediate frequency, increasing the noise figure.

On the other hand, at least in Europe, the head end unit output is typically from 900-2100 MHz, to allow terrestrial antenna signals below that at standard VHF/UHF channels to be transported in the same cable. For a dedicated system, the lower frequency limit could be considerably lower.

Cable TV companies have used for decades high linearity transmitters and receivers amplitude modulating the laser with the whole cable-TV band, originally containing dozens of analog signals and later up to

256QAM digital signals. No doubt these are expensive.

On the other hand, down converted satellite signals were originally constant amplitude FM signals, later on BPSK or QPSK and just recently with DVB-S2 up to 32APSK. The linearity requirement is far less.

Reply to
Paul Keinanen

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