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Topic # 13194 27-Apr-2007 11:31
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I have Sky satellite with standard Motorola STB. Also VHF/UHF aerial cabled seperately (from Sky) into house. Both dish and aerial have 14m runs and use RG6 Sky approved cable.

I want to distribute RF and Sky around the house to a couple of TVs and couple of TV tuner cards (yet to purchase).
Had been thinking of feeding VHF/UHF aerial into 'RF In' on Sky STB and taking 'RF Out' (which includes the Sky channel modulated to UHF signal) from Sky STB to a TV distribution/splitter/amplifier box. It is also possible to feed a modulated DVD signal into the box (DSE sell a Hills box).
This enables each TV/TV tuner card to individually choose any VHF/UHF broadcast and to 'see' the Sky channel as selected on STB and watch DVD. Lounge TV would use composite or component from Sky STB and DVD player. Could also incorporate remote control extender either stand alone or via the coax. Appreciate everyone 'sees' same Sky channel with only one Sky STB.

What length of runs can you use before needing an amplifier as opposed to just a splitter. All runs within the house would also be RG6 cable and F connectors. The runs could be up to 16m each.

Recently I have become aware of the Freeview launch and want to make sure that what I do is 'future proofed' so I can take advantage of any additional Freeview channels not broadcast on FTA VHF/UHF.
Appreciate that Freeview needs a decoder for each device if you want individual channel selection, but at least we could buy TV tuner cards that decode Freeview for the PC's.

If we went with Freeview satellite, how do you distribute Freeview signal to each TV and also allow that TV to select the Sky channel currently 'on' via the Sky STB. Ie does Sky STB output via it's RF Out the full frequency range (incl satellite frequency) or just up to 806mhz covering VHF/UHF. If it covers full range (and assuming Sky have moved to horrizontal) I could take the feed off the dish into back of SKY STB and then distribute RF Out (on basis it covers satellite frequency) around the house using distribution/splitter/amplifier box that covers full frequency range.

If Sky STB does not RF Out the satellite frequency range, then I would have to split the feed from the dish into the Sky STB and direct to distribution box and also take the RF Out from Sky STB to distribution box (at UHF frequency) to get the Sky channel into the distribution box.

The key to all this is what frequency range does the Sky STB cover at RF Out.

Another alternative is to use Freeview terrestrial when available and have the Sky STB RF Out and the Freeview UHF aerial both feed into distribution box. Such box would only then need to cover VHF/UHF range (DSE have one of these from Hills).

Any other suggestions or issues with these alternatives.


Steve

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  Reply # 68643 27-Apr-2007 12:00
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Hi Steve,

My current set up (which is against Sky's T and C's) is:

Satellite feed: Sky satellite feed -> FTA STB -> SKY STB.

This works well at the moment with the FTA STB on either TV 1 or TV 2 on the Optus D1 12671 transponder which is not encrypted and is a Vertical Polarity signal. The FTA box is an Antronic one which is sold on Trademe. It has a through feed so both STB's access the satellite LNB fine as long as I don't select a Horizontal feed on the FTA STB (which TV3 and TV4 currently are).

The FTA box has an RF out which modulates on any UHF frequency I choose. This goes:

FTA -> SKY RF IN -> Coax feed to Hub. This Hub feeds the whole house and is a clipsal Starserve which came with the house. It is just a basic model which has a 12 volt transformer and boosts the coax feed to the rest of the house.

For the DVD input you can get a cheap modulator from Jaycar for $24.00 (not including a 12 volt powerpack) which will modulate the DVD signal to UHF. www.jaycar.co.nz CAT. NO. LM3873.

So, with my current setup, I have two channels tuned on each TV in the house, one is the sky box and one is the FTA box. I don't have the modulator as I have a wireless AV sender I was given. This also allows me to change the channel on the Sky box from another room as it has a remote control extender.

I don't have a VHF or UHF aerial on the roof at all.

From what I can gather you are OK running up to three TV's off a single splitter before you need to get into an amplifier.

I hopes this helps a bit.

Cheers.






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  Reply # 68645 27-Apr-2007 12:11
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steve2222: The key to all this is what frequency range does the Sky STB cover at RF Out.

Any other suggestions or issues with these alternatives.

The Sky STB RF Out only includes VHF and UHF channels SFAIK.

Another important consideration is to make sure that the RF modulator used with your DVD player is on a selectable channel and that it doesn't output at too high a signal level or it can block nearby channels.  I remember this used to happen with our old VCR that output on VHF with the effect that it blocked TV1 completely while it was switched on, even though TV1 was on a different Low-band VHF channel.

The only way you can get access to the full range of satellite channels is to split the IF signal coming out of the LNB (on your dish) before it enters the Sky STB.  Apparently it is possible to combine this satellite IF signal with VHF and UHF channels using a diplexer, but any further details would be best provided by our resident experts:

SBiddle  or  Cyril

Cheers,
Grant.

P.S.  Welcome to Geekzone Smile

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  Reply # 68650 27-Apr-2007 12:47
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Essentailly No problem doing what you want to do, but something to be aware of is that if Macro vision is enabled on the disc and your player has not been doctored to ignore it then you may have difficutly viewing some DVD's due to macro vision issues. You also could save some money and use a VCR as a modulator, but again macrovision may foul things.

If you want to distribute both LBand IF from the dish LNB and VHF/UHF then you can use a diplexer, you will require one after on the final combined V/UHF RF feed and one at each terminal point. I recommend that you place a 75ohm Fcon termination on any LBand port of a diplexer not used. A diplexer has three ports, V/UHF, LBAnd and Combined.

As for losses, you most likely will find that you will need an amp after you have combined the Antenna/SkyRFout/DVB-SRFout/DVDRFout, then push this combined signal into a diplexer with the dish feed, and the split out.

There are plenty of pitfalls with all this, and quite honestly I recommend a competent antenna/Sky installer do it all for you so he can check the levels with a FeildStrength Meter of both V/UHF and Lband are balanced through out the process otherwise the wheels will fall off rather quickly.

Cyril



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  Reply # 68685 27-Apr-2007 16:38
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Thanks for your help and the warm welcome.

If I go with IF Lband being piped around the house coupled with UHF (for modulated DVD and Sky STB RFOut) over the same cable, is there a recommendation for a TV Tuner card that can decode Freeview DVB -S as well as accepting the UHF signal from the one RG6 cable?

Steve

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  Reply # 68688 27-Apr-2007 17:00
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I have not dabbled in the area of PCI DVB cards, so probably not the best to ask, however here is a card that has both DVB-S and analog terrestial. But dont ask me if its a good one or not I dont know. As you can see it still has two tuner inputs (one for LBand and one for U/VHF) so you still need to supply an external diplexer to seperate the two off a common cable, diplexers only cost $15-$20 each and are similar sized and look just like a two way Fconnector splitter. Obviously you will need to have installed one as a combiner before splitting the signal about the house.

Again, you will need to take account of levels for both the Lband and V/UHF sides of the system, I would advise you deploy someone with experience and a signal level meter to ensure a satisfactory outcome.

Cyril

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  Reply # 68690 27-Apr-2007 17:38
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If you want to future proof,a multiswitch may be your best bet.Then with the appropriae diplexer,you can have Sat
& Terrestrial on all outlets ie you  can put a STB on any outlet.then when the DVB T starts, you can have variuos combinatons
Bear in mind you will lose approx 10db on terrestrial, I concur with Cyril'Hire a Pro'

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