PDA

View Full Version : Hooking a satellite to 4 TVs


capacitor
08-13-2000, 12:22 AM
If one has a Dual-LNB satellite, and has the multi-switch from RCA that can connects to four TVs or receivers, how many receivers does the installer need for all 4 TVs to function independently?

Homer
08-13-2000, 02:13 AM
Okay, first off, you do NOT need a separate LNB for each TV. If you have a dual LNB, you can connect as many TVs as you want. All you need are the boxes themselves connected to each TV.

The satillite signal is received in 2 parts. We'll call them 'left' and 'right.' If you have a single receiver hooked up, you only need one LNB, because it can just switch between l and r as it needs to. BUT when you hook up 2 receivers, you need a dual LNB. You CAN use a single LNB, and split the signal, BUT, since it is receiving from two sources, changing the channel on one may force the channel on the other TV.

The solution is to get a dual LNB. That way, if receiver 1 is using the R channel, receiver 2 can use the L channel, and vice versa.

If you have more than 2 receivers hooked up, you still only need 2 LNBs, because if one receiver is on the R signal, and another is on the L signal, the third can just share whatever 'side' it needs. And so on and so forth.

Make sense? Note to purists: This is purposely extremely simplified.

--Tim

archmichael
08-13-2000, 02:19 AM
Homer is right. I work for that particularly company, and his is a pretty good explanation.

You have to remember that it is an encrypted signal that needs to be decoded. That is why your TV's picture-in-picture doesn't work very well with DIRECTV systems. It can only decode one channel at a time. Some of the next generation boxes will have dual decoders, which will allow the box to generate a PIP.

capacitor
08-13-2000, 02:51 AM
Okay, thanks for the information. Let me clarify. How many of these "boxes" being referred to do I need in order for each of the 4 TV's to be independent from the channel to which another TV connected is tuned? (Each person using a different TV have very diffferent viewing habits.) I have been given conflicting answers to that question, between Sears, Circuit City and Radio Shack. Would one 'master' receiver 'box' do, or do I need two, three, or all four, one for each TV?

archmichael
08-13-2000, 03:34 AM
Four. One for each TV

pldennison
08-13-2000, 09:18 AM
Corollary question: If you have the reciever hooked up to your VCR, then your TV, can you do the "watch one channel tape another" thing, or would you need a separate receiver for your TV and your VCR?

justwannano
08-13-2000, 09:58 AM
I'll take s stapb at it guys
The big picture
I'll explain Cband because thats what I have experience in.

The satellites are only 12 channels but they get away from this by polorizing the signal. Channel 1 is horizontal channel 2 is vertical. Both use the same frequency. Thats what phe polorotor is for.It recieves the signal. Dual lnbs are mounted at right angles to each other so one is receiving hor the other vert.Thus a dual polorotor which really isn't a polorotor any more.
Obviously to recieve all 24 channels you have to switch between the lnbs.
OK now we have the signal to the house.
In the house you must have a switch method for each reciever. Someone mentioned master and slave units. The master supplies the LNB with the proper voltage to operate. The slave just uses whatever is fed to it.They can be exactly the same model reciever except the slave has a dc block installed.
Two coax lines have to go to each reciever one for hor the other vert.
On C band you have the option of moving the dish. This becomes more complicated since some satillites use channel 1 hor and some vert.
I've left out hookup instructions because it gets kind of hairy.

justwannano
08-13-2000, 10:06 AM
Next time I'll reread the question before posting. If you want a reciever to operate independently there first must be a reciever. FOUR is the correct answer

Katie Scarlett
08-13-2000, 05:37 PM
Just a note....DON'T let the retailers trick you into buying 4 SYSTEMS....you only need one system and 3 stand-alone units. A system includes the dish and LNB, a stand alone is just the IRD (box, receiver, that black thing that goes on top of the TV) This is something that many consumers don't realize and the sales people have a vested interest in NOT explaining this to you. I've seen too many people buy at a major retailer and be given bad information. When in doubt, contact a local SATELLITE dealer, NOT a major retailer. In fact, if you are in AL, AR, MO, MS, TN, KY, LA, GA, VA, WV, PA, OH, MI, WI, or in some parts of FL, I can get you information on dealers that actually KNOW what they're talking about, or about installers nation-wide.