Best option for Freeview (strange situation ahead)

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#275299 22-Nov-2009 21:35

Darn!

Thanks for the clarification Cyril. What would be the most cost effective option for me then?

- New LNB on my 1 meter dish to feed my computer directly
- New dish just for Freeview
- Splitting the cable from the LNB on the current dish after the booster thing and running a separate coax cable to my computer

Do I need an inline booster after 50 or so meters of RG6 cable or is it good up to 100 meters?

Thanks for your help guys. This is helping me a lot! :)

cyril7

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#275302 22-Nov-2009 21:40

Hi, you did not explain about the current splitters in more detail, purhaps you should do that with a photo.

you say there is a 3way and a 4way, I presume the three way splits the Lband (dish) feed to the three recievers, and the 4way is used to combine the three modulator outputs (black boxs), but could you confirm that. Also is there a V/UHF antenna feeding into all this and if so are there active filters on the antenna feed or just a broadband couple.

Cheers
Cyril

DravidDavid

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#275310 22-Nov-2009 22:18

There is no UHF aerial installation. The Freeview website states it would be "Unlikley" I would pick a UHF signal up from Wellsford. However I have spotted a house with a rather large one on their roof. I should ask them about it.

Here is the current setup:

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_001.jpg

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_002.jpg

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_003.jpg

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_004.jpg

The black box is some kind of modulator. The three decoders on the racks and splitters.

The connector next to the round multibox plug above the black power supply at the bottom left hand corner of photo 4 is where the satellite cable first meets an intersection. Since the connector is plugged in, I suspect it is some form of booster?

Maybe you can make more of it :)

cyril7

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#275545 23-Nov-2009 17:40

Hi, I did produce a quite detailed response earlier today, but have only just noticed that it did not get accepted by the server, purhaps I took to long to write it, very annoying.

Anyway the first coupler you see is the injector to power the LNB. I presume from there there is a way splitter to each of the STBs, so is there not one spare.

Its odd that you only have 3 sky channels distributed to the rooms. The FTA TV1/2 satellite signals have been there for 8yrs or more, well pre freeview, surprising that you have not used them to at least get TV1/2 for the rooms.

Anyway if there is a unused port on the 4way splitter from the dish then there is no reason you cannot use it. You mention there is a 3way splitter as well where does that fit in to the system, as it appears the modulator is a 3 or 4channel unit with internal combiners.

If there is a spare port and you use it you may find at the end of 50meters the signal may be a bit below the recievers threshold, so an inline amp (14-16dB gain should be fine) between the splitter and the 50m of cable may be needed, but you should place it up at the splitter not down at the new reciever.

Purhaps you could explain what splitters are curently in circuit and where.

Cyril

DravidDavid

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#275649 23-Nov-2009 22:24

Ok.

I need:

- 1x 14-16dB booster
- 6 to 8 port splitter to replace the current 4 port splitter
- 50 meters of cable

The only splitters I can find around the place have only 10dB gain. Is the booster something I would have to plug in? Should I buy two sets of 25 meter cable so I can place the booster in the middle rather than each end? Or is plugging the booster "directly" into the splitter ok?

I can't really explain the splitters in more detail, as I have no idea what does/goes to what myself.
It looks like there is one intersection for the modulator thingy and another intersection to separate the satellite feed from the RF feed to the units.

It looks like the splitter with the most coax cable coming out of it is the one I need to replace. So that is what I will do. *crosses fingers*

Now I just need to find a 16+ dB splitter somewhere.

richms

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#275658 23-Nov-2009 22:47

any chance of drawing a diagram of how its all done at the moment, I cant follow the picture and the words are too confusing for me.

A satillite booster will not need to be plugged in, it gets the power from the coax cable, so your PCI card will power it up the cable.

Richard rich.ms

DravidDavid

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#275979 24-Nov-2009 22:27

Thanks for all your help guys!

I have just decided to go with a separate dish. Its less risky, and I can chop/change or upgrade anything on my own dish rather than the motels.

It works out much cheaper to buy a package deal with 90cm dish, cable, STB and LNB over wiring 80 meters of RG6 cable from a splitter with boosters out to wazoo. I also made a deal with my parents and they have agreed to split the price as they want it too!

I can get a 90cm dish, wall mount, LNB, cable and set top box for $238.95 NZD from:
http://www.freeviewshop.co.nz/product_info.php?products_id=347{16}47{15}45{18}53{29}188

Is this a good price?

Thanks again guys!

Sharesies

Trade NZ and US shares and funds with Sharesies (affiliate link).

DravidDavid

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#277295 28-Nov-2009 20:10

I didn't think it was necessary to make a new thread to ask this question, so I will ask here.

Can I run the cable from my LNB into an 8way splitter (only 3 ports occupied) and then 30 meters from the splitter to a two way splitter where it will connect the STB's? Can I get 30 meters without a booster? The other unrelated thing is all the splitters are power-pass. Will this blow something up if all the STB's and DVB-S PCI cards connected are able to pass on power?

Cheers! :)

richms

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#277323 28-Nov-2009 22:22

Probably will be fine, the attenuation will see a drop in signal but as there is almost no noise domestically in the L band (other than dect phones) you dont really see much of a change to the carrier to noise even with considerable loss.

The 8 way with the ports unterminated will probably be more of a problem than attenuation, but depending on various things if you do end up with some weird notch filtering happening that affects you just swapping splitter ports around to different cables should clear it up.

Far from ideal however.

Richard rich.ms

DravidDavid

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#277326 28-Nov-2009 22:27

What is the most ideal way to split the signal to 4 or 5 STB's/DVB-S cards without blowing something up or loosing signal then? Do I just buy a booster for the longer runs (for example the 30m run). I'm not sure what "unterminated" means.

This is these where the splitters I was looking at buying:

http://www.trademe.co.nz/Browse/Listing.aspx?id=256234315

http://www.trademe.co.nz/Browse/Listing.aspx?id=256234423

:)

richms

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#277345 28-Nov-2009 23:24

unterminated means a splitter without anything connected to the port - it makes an impedance mismatch as the signal bounces back into the cable. Too many of them and you get reflections going back and forth making the quality drop heaps, even tho the strangth may still show good. Think large echoing room and trying to understand people, its not the loudness, its the reflections making it hard to hear.

Best way is a single splitter, all unused ports with a 75 ohm terminator in them, they are available at mastertrade/corys etc, just screw into the ports. Well better is to not have unused ports since that means you are not wasting signal into a terminator.

Cascading splitters means that you have more loss on those ones, and that's normally done at the end of a cable so its worse again. The other issue with cascading splitters is that the ones going thru 2 splitters may end up with too much voltage drop to make the LNB go into horizontal polarity since each splitter will drop 0.7v of what is available, and the cable loss as well over that length means you may be below the 15 or so volts that most trigger at.

Also a 30m run means it may be going between buildings. Make sure that they share an earth before putting cables between them, otherwise bad things with ground loops may happen.

Richard rich.ms

eXDee

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#277346 28-Nov-2009 23:24

I'm very surprised there isnt a product for Sky, or even standard free to air DVB-S which does a large distribution setup for motels.
I know very big hotels will have an entirely automated/computerized system with all the pay per view movies etc, but for the smaller ones that want to offer sky or freeview it doesnt work out that good.

DravidDavid

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#277352 28-Nov-2009 23:32

So if I purchased a 4 port power-pass splitter that connected the 2 DVB-S cards and 2 STB's (which would be all I would need) I would not need to terminate them since all the cables are connected and I would have less attenuation improving strength and quality? Also avoiding burning my LNB to a crisp by using a power pass splitter?

The 30M RG9 cable is going though walls in the house in order to get to my room, it is not crossing houses.

richms

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#277354 28-Nov-2009 23:33

There is a few in the UK that will take 5 DVB-T channels and output 5 analog channels on various UHF freq's, which would be good for places that want to get proper aspect off the FTA channels into a whole lot of TVs or for some reason want tvnz 7, but I have not seen one that does mpeg4.

As for satilite, most places get by with the modulators in the boxes and then a little conditioning of the levels before distribution. Without a spectrum analyzer its almost impossible to get working right. And if you are a hotel then you can afford a few 100 for an installer to do all the work for you IMO...

Richard rich.ms

wmoore

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#277359 28-Nov-2009 23:37

DravidDavid: There is no UHF aerial installation. The Freeview website states it would be "Unlikley" I would pick a UHF signal up from Wellsford. However I have spotted a house with a rather large one on their roof. I should ask them about it.

Here is the current setup:

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_001.jpg

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_002.jpg

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_003.jpg

http://i135.photobucket.com/albums/q131/13CentKiller_Sniper/skysetup_004.jpg

The black box is some kind of modulator. The three decoders on the racks and splitters.

The connector next to the round multibox plug above the black power supply at the bottom left hand corner of photo 4 is where the satellite cable first meets an intersection. Since the connector is plugged in, I suspect it is some form of booster?

Maybe you can make more of it :)

Who did your sky install ? What a mess. Shouldn't those decoders be on proper shelves.
And why is it (not getting at you, but generally) when people take photos of stuff, it is usually too dark to see
or out of focus, or they focus on the wrong part.

I think as others have said it would be best to draw a diagram of the wiring.

"In the end, it's not the years in your life that count. It's the life in your years." -
-- Abraham lincoln

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