Single/Dual LNB & Multiple Receivers

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Jake_E

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Jan 1, 2007
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Fayetteville, NC
Been a while since I've posted here (still haven't set-up a system yet, either, more on that in a bit).

I'm looking at setting up 1 (possibly 2, which would let me grab the whole sky, almost) T-90s and in an effort to get 2 deg separation I was thinking about going with single LNBs for some birds. Mainly, the ones that are predominantly feeds, i.e. I'm the only one that's going to watch them, no one else in the family will.

If I set up 2 T-90s, I can do 80 deg of sky, but that will require me to grab birds that are 2 deg apart on the same dish. I've read through Iceberg's thread on his experience with the T-90 and anything else I can find on it. In that thread there was a nice, small LNB, but it was a single. Since I'm looking at over 16 birds, being able to use single LNBs for some of them will save a lot of work. The only problem, that I could see, is that at some point I will have up to 6 receivers (1 PC, 1 office, 1 MBR, 1 family room, possibly my daughters' rooms later on). The traditional answer is, "if you have more than one receiver, you need a dual."

Well... What if we really aren't going to have anyone trying to watch some of those birds at the same time, let alone at the same time on different TPs/polarizations? Will a single be good?

If so, does that make a difference when it comes to switches? I've seen a couple of layouts that will allow 16-32 (and one had 64) birds (or 8/16/32 dual LNBs), will they still work with single LNBs? Not to mention that I'm looking for a switch that will allow the terrestrial antenna to piggyback on the same wires.

Its quite an ambitious project, I know, but if I'm going to do it, I'm going to go all the way on the first shot.
 
Ku band only?

A guick scan of FTAlist shows 16 satellites.
A similar peek at Global-CM shows 19, if you ignore a couple useless Dish birds.

Maybe a first step would be to list and categorize the satellites of interest.
A bit of input from the feed-hunters might add or delete some satellites.
Supporting more than four receivers for any particular LNB gets spendy.

I assume a 2x4 switch is needed for any multi-receiver LNB, and maybe a 2x8 if you insist on all six receivers being able to access it.

So, does this make three categories?
1) feed only, use a single output LNB, no switch
2) 4 receiver support, dual output LNB, use a 2x4
3) up to 8 receivers, dual output LNB, use a 2x8

I didn't mention feeding your OTA through all the switches.
There's a lot of signal loss through switches, splitters, and diplexers, so you may need to look for alternate solutions in that department.
 
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With my T90, I can get 2 degree spacing, meaning 2 lnbf's side by side, but I can't get 3 lnbf's together at 2 degree spacing. You're right on needing dual lnbf's for your project. I think you're going to need something like a 4x8 multi switch to be able to use 6 receivers. I have 13 lnbf's (being used like 12 lnbf's) from 129.0w to 83.0w. I currently have four 4x4 muti switches, using it with an EMP-Centauri 8x1 Diseqc switch for one receiver. I have three more 8x1 switches for three other receivers. It works quite well, but I need some more dual lnbf's and four more 4x4 multi switches. I'm planning on setting up a P* dish I recently inherited for 72.0w, 74.0w and 79.0w. This project is not cheap, but it's worth it in the long run. Good Luck with your adventure!

Al
 
Yea, I think VoomVoom is right.
If you use 4x4 or 4x8 switches for every two LNBs, that probably makes more sense than one 2x4 or 2x8 switch for every LNB.

Then, the 4x- switches select which LNB by 22khz tone, and which polarity by voltage.
Follow those with an 8-input diseqc to select 1 of 16 birds.

Is that the right way to configure, guys?
 
yep

at one point I had 8 LNB's on 4 4x4 multiswitches going to 4 4x1 diseqc switches. When I had the 8x1 I had a couple 22k switches in the batch too
 
Well, after cruising through the lists and looking for stuff that sticks out to me, this is the list I have so far (including the DBS birds for subscription stuff, know that I'll need the reverse circular, etc. but I just put them in this list so it provides the whole picture).

129.0 West - EchoStar 5 (Circular)
123.0 West - Galaxy 10R (Linear)
121.0 West - EchoStar 9 (Linear)
119.0 West - EchoStar 7 (Circular)
113.0 West - SatMex 6 (Linear)
110.0 West - EchoStar 8/10 (Circular)
105.0 West - AMC 15 (Linear)
103.0 West - AMC-1 (Linear)
101.0 West - AMC-4 (Linear)
97.0 West - Galaxy 25 (Linear)
95.0 West - Galaxy 3C (Linear) (?)
93.0 West - Galaxy 26 (Linear)
89.0 West - Galaxy 28 (Linear)
87.0 West - AMC-3 (Linear)

Not sure if Galaxy 3C is worth it or not. Basically my big things are the foreign stations (Galaxy 25 pretty much takes care of that), the Dish stuff for the subscription, and then worthwhile birds for feeds (which I know next to nothing about).

For those of you that have been around the game much longer than I have, what would you add or remove to the above list? What good feed birds am I missing, etc.

87 W to 129 W should be possible, and I might be willing to try for wider, but at this point I think I'm good. While doing two T-90s is tempting, the cost would be too much for the gain, IMO.

This list is only 14 birds, so it will be much easier to figure out the switching issue, and I should be able to use dual LNBs for all of them (unless it would be pointless from someone's experience to do so).

So... Lay it on and don't hold back :D I will truly appreciate it.
 
Well, if you are subscribing to Dish, take all their birds out of the list.
You can have LNBs at 110, 119, 121, and 129, but they don't factor into your switching matrix.
Those would use dedicated switches and be hooked only to the Dish receivers.
Your Dish receivers won't command the unique switch matrix you are building for the FTA receivers.
If you receive those satellites now, I'd put up my T-90 and get it operational for FTA, and then as a very last step, try to integrate the Dish LNBs.

You might also have more wiggle room for the FTA LNBs you need, if you don't have to deal with all those circular LNBs being in the way. :cool:
 
what subscription do you have for Dish? Maybe you dont need 105,121,129. 105 had some locals but those are mirrored on 129. 121 has Int'l subscription programming and 129 has HD
 
We've got international and HD stuff. Is everything on 105 mirrored on 129? I'll have to go take another look at the EchoStar KB.

What about the FTA stuff & feeds? I know you have some input on those, I'm sure. :D
 
You were right, 105 doesn't apply to us...

Not to mention we don't have anything pointing at 105 right now anyway :( Some days aren't my best, lol.
 
Your's is simular to my T90 set-up:
129.0w = Linear, horizontal only
123.0w = Linear
119.0w = Circular, vertical only
116.8w = Linear
113.0w = Linear
110.0w = Circular
103.0w = Linear
101.0w = Linear
97.0w = Linear
93.0w = Linear
89.0w = Linear
87.0w = Linear
83.0w = Linear

I have 13 lnbf's, posing as 12 lnbf's, with 4 @ 4x4 multi switches and 1 @ EMP-Centauri 8x1 Diseqc switch. I have 3 other 8x1's, but I haven't moved the dish to it's permanent home, yet. Good Luck on your project!

Al
 
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