14 True receivers - how many LNB's needed?

[Archie Pelago]

Another tech question, this time for the satellite tv boffins.

Need to supply 14 True Move receivers for a ship - and I am not sure how many LNB's this requires. Is it one LNB per unit?

Or does it depend if they are being set up in different physical locations on the ship?

Same question for CTH receivers - they need 5 of those, would I need to get the 5 matching LNB's?

Sorry if this sounds like a basic question - this is not my area of expertise, and many google searches left me even more confused.

[Jdietz]

You'll need something like this:

http://www.satellitesuperstore.com/emp-centauri_multiswitches.htm#5in

for True you will only use one input, but can use the others for different satellites. Just need the one dish / one LNB for now.

Added wiring diagram sample. Diplexers are only needed if you also add a terrestrial antenna. Otherwise outputs can go straight to the Sat. boxes.

AFAIK CTH is on the same satellite cluster, so just use a CTH box instead of a True box on the multiswitch output and all will be well.

[Pib]

How many dishes are involved? If one dish is going to be involved you need one LNB...then that LNB feeds a multiswitch which inturn feeds the individual TVs.

[gerry123]

hi the most i have seen is lnb x2 outlets however there must be multi set ups for hotels /condos etc isuggest you go off to your local sat shop and ask them or google lnb a see what you get

[AnotherOneAmerican]

You only need 2 LNBs for each satellite company (1 Horizontal and 1 vertical).

Those 2 feeds can then be split and distributed to all the receivers.

[Archie Pelago]

Hi, thanks for the replies so far (you guys are quick).

I went to 3 local satellite shops today - when I mentioned the receivers were going on to a large ship, this had them stumped and I get 3 different answers from 3 different shops (1 LNB, 2 LNB's and 1 LNB for each of the 14 receivers)

So I went back to google, and although there were plenty of threads on different forums, I couldn't find anything that addressed my specific situation - hence posting here.

[RichCor]

One Dual-LNB per satellite.

If all of your TrueVision programming content is delivered over a single 'bird' then you need

one Dual-LNB, with both 'feeds' connected to a single 'multiswitch'. Each Set Top Box is then connected to the 'MultiSwitch' with an individual coaxial cable.

Size the multiswitch to the number of Set Top Boxes.

The Set Top Boxes will autoselect the correct Horizontal/Vertical signal feed provided by the dual-LNB

[Archie Pelago]

I do love this forum. Really appreciate the contributions, many thanks

[Pib]

You only need 2 LNBs for each satellite company (1 Horizontal and 1 vertical).

Those 2 feeds can then be split and distributed to all the receivers.

Actually, TrueVision signals/channels are horizontally polarized therefore you only need a one output LNB. CTH probably the same way. That's why you see all these small dish systems around Thailand with just "one cable" running up to the one output LNB. Now when you want to start viewing other transmissions/channels that can be transmitted in horizontal or vertical polarizaiton and you want to use just "one" LNB, well, that's when you need a two output LNB feeding a multiswitch so multiple receivers attached the multswitch can simultaneously tap into channels that are vertically or horizontally transmitted. It's like the multiswitch shown in RichCor's post above...the 13V/Vertical feed and the 18V/Horizontal feed which would connect to a 2 output LNB.

[RichCor]

What Pib says about all TrueVision or CTH programming streams being within the same polarization feed are correct for the Ku Band (small dish setup) -- they are both at the same location they are on opposite polarization feeds.

Ku Band

TrueVisions on Thaicom 5 at 78.5°E Horizontal Feed only

CTH on Thaicom 6 at 78.5°E Vertical Feed only

C Band

CTH on Thaicom 5/6 at 78.5°E both Horizontal and Vertical utilized

To cut down on cost I would recommend a single largest-size Ku dish, with a Dual-LNB, and run each separate LNB output to a single-input MultiSwitch dedicated for TrueVision receivers, and the outer LNB output to a single-input MultiSwitch dedicated for CTH receivers.

[Pib]

Just to hurt everyone's head a little more who are not familiar with "multiswitches", here's a diagram showing 4 dual-output LNBs (C and KU band LNBs) feeding into a multiswitch and then the multiswitch feeding a variety of receivers. To each receiver it only sees whatever satellite(s) it is set for. The LNBs could possibly be mounted on the same dish or on separate dishes.

[jimmym40]

Maybe I'm missing something. You say these are going on a "ship". How in the world are you going to direct the LNB to the satellite? The dish must be stationary and not move. If the ship moves just a few degrees, you will loose the signal.

[thedemon]

Maybe I'm missing something. You say these are going on a "ship". How in the world are you going to direct the LNB to the satellite? The dish must be stationary and not move. If the ship moves just a few degrees, you will loose the signal.

I've noticed that many of the barges and tug boats going up and down the Chao Praya have TRUE dishes so it must be fairly easy to solve this problem.

[joncl]

They use a simple gyro lock dish for each satellite normally on the Ku band only so even if the ship moved the dish stays locked on the satellite selected..