Thread Tools Display Modes
Old 09-25-2002, 04:15 PM
ready29003 ready29003 is offline
Join Date: Apr 2002
Posts: 450
how does directv do more than 2 tv's?

I know a dual LNB thing on your dish gives you 2 feeds, but how do they handle it if we want more than 2 feeds? I figured someone here would be able to answer faster than Directv support.
Old 09-26-2002, 04:32 AM
Bryan Ekers Bryan Ekers is offline
Join Date: Nov 2000
Location: Montreal, QC
Posts: 57,520
Re: how does directv do more than 2 tv's?

He dates them on seperate nights.
Old 09-26-2002, 07:36 AM
kanicbird kanicbird is offline
Join Date: May 1999
Posts: 18,861
I think you need another dish
Old 09-26-2002, 10:02 AM
Algernon Algernon is offline
Charter Member
Join Date: Nov 2001
Location: Milwaukee
Posts: 2,732
I'm not sure what you mean by a "dual LNB thing", but it doesn't matter if all you want is to have more than one or two televisions getting a satellite signal. (I think "dual LNB" enables Picture-In-Picture, and might allow you to tape one program while watching another.)

I have a single DirectTV satellite dish. I'm running three televisions off the single feed from the dish. However, at each television you have to have a separate satellite receiver box. The selection of which channel you want to watch is controlled by the receiver. It is like the cable boxes of old.

With a separate receiver for each television, all three televisions can be showing a different channel. All with a single satellite dish.

Now, you could get by with only one satellite receiver, but then all three televisions would be forced to watch the same program.

Or, assuming that "dual LNB" sends two separate channels, you could have two televisions controlled by the "dual LNB" receiver and a third television controlled by a separate "single LNB" (?) receiver.
"Time flies like an arrow, fruit flies like a banana." (Groucho Marx; but also used to test a language recognition algorithm)
"The essential is invisible to the eye." (The Little Prince)
Old 09-26-2002, 11:26 AM
quar quar is offline
Registered User
Join Date: Sep 2001
Location: Flower Mound, TX
Posts: 31
Each LNB talks to exactly one receiver. If you have a dual dish and more than 2 receivers, you'll need a can help you out...
Old 09-26-2002, 11:26 AM
ready29003 ready29003 is offline
Join Date: Apr 2002
Posts: 450
yea that makes sense, why do they insist you have a dual thingy rather than a single thingy if you want multiple televisions? It seems you can have multiple tv's with just one cable coming from the satellite..but they say you have to have 2....if you want 2 or more?

dunno.. Makes no sense. Must be a scam.
Old 09-26-2002, 05:25 PM
Belrix Belrix is offline
Join Date: Mar 2002
Location: Denver, CO, USA
Posts: 2,733
The dual-LNB thing is because Dish Network has two satellites. The satellites are close enough in the sky (10-degrees, I think) that they can use one dish and two LNBs about 10-degrees apart.

Each cable from the LNB combines with some little gizmo and runs into the one receiver.

If you want to use more than one TV then you have to get more than one receiver. Dish network has a PDF diagram here of how everthing connects. There's other installation diagrams here to their other setups.

Old 10-01-2002, 04:54 PM
Belrix Belrix is offline
Join Date: Mar 2002
Location: Denver, CO, USA
Posts: 2,733
For the record, after going back and looking, you were asking about Direct TV and I answered for "Dish Network" aka "Echostar".

Never mind...
Old 10-01-2002, 05:45 PM
JimOfAllTrades JimOfAllTrades is offline
Join Date: Mar 1999
Location: Utah
Posts: 1,633
I have Dish Network, not Direct TV, but it may be similar. I have 1 dish, and 4 boxes for watching separate channels on 4 different TVs.

As it came, the dish had the capability to run 2 decoder boxes, and I paid (and pay each month) a few bucks extra for the extra 2 boxes and the capability to feed them. As you look at the dish, there appear to be 2 "receivers" next to each other, each getting the signal from the satellite. I guess each one of these is a "Dual LNB", or something similar. The “focus” point of the dish must be wide enough to allow the 2 receivers to both get enough signal. There are 4 coax lines (2 going to each receiver) running from the dish into the house, and then 1 goes to each decoder box.

I was told if I wanted more than 4 boxes, they would need to install a second dish, which could then handle up to another 4 boxes, and so on.

My brother just had Direct TV installed, and from what he told me, it seems to be about the same story.

Old 10-01-2002, 06:39 PM
scotth scotth is offline
Join Date: Aug 2001
Location: Dallas, TX
Posts: 1,325
The key piece is the multiplexer on the back of the antenna.

For DirecTV things work like this.

1) Dish focuses radio waves for as many LNB's as you have (I have 3, round dishes can only do one, each LNB hits a different satellite).
2) Each LNB picks up vertically and horizontally polarized radiowave. It puts out signals of each polarization on seperate output jacks.
4) Two cables from each LNB feed a multiplexer.
5) The multiplexer feeds the reciever(s). The multplexer must have an output jack per reciever. The receiver puts a DC bias on the cable connecting it to the multiplexer. Based on the DC bias, the multiplexer choses which LNB/polarization combo to send to the reciever.
6) My multiplexer supports 4 receivers, I have them seen them with as many as 12 outputs. Special high capacity units are available for apartments and such.
7) A seperate cable must be run for each receiver from the multiplexer. For DirecTV, this is generally located on the back of the dish and isn't too convenient sometimes.

In summary, the multiplexer allows multiple output (to receivers) to choose one of x number of LNB inputs (6 in my case).


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 06:40 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.

Send questions for Cecil Adams to:

Send comments about this website to:

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Copyright © 2018 STM Reader, LLC.

Copyright © 2017