Scientific Atlanta 16 foot dish

[1captain]

Hi Linuxman, hope you had a nice New Years.

all sounds great for having a fixed C-band dish, but the only problem that you may run into maybe be to much signal, yes that right "too much". I ran into this years ago when the DSR-920 first came out, customer had a 14-foot solid Channel Master dish an it would cause the 920 to freeze its picture, we changed several lnb's an other 920 receivers, an had hours on the phone to G.I. an 1 of their techs sujested to antuate the IF signal, an got a IF antuator an it stop the frezing problem. now this was with a 920, have never ran into that problem agin, now the 922 that may not be a problem or it may, but most people don't have that large of a dish, so signal level is very important, but their is a point when their is to much also.

an the same thing aplies to TV sets when they are real close to the transmitter they will over load the tuner an have problems receiveing that station or other stations that may be week, same thing also goes true for satellite signal, but those receivers (commercal) will take more imput than what a residnetal receiver like a 920 or 922 will, it all come back to the agc an how it set an controlled in the receiver.

Good luck getting that dish will be a keeper, an a nice 1 at that.

 

[linuxman]

Hi Linuxman, hope you had a nice New Years.

all sounds great for having a fixed C-band dish, but the only problem that you may run into maybe be to much signal, yes that right "too much". I ran into this years ago when the DSR-920 first came out, customer had a 14-foot solid Channel Master dish an it would cause the 920 to freeze its picture, we changed several lnb's an other 920 receivers, an had hours on the phone to G.I. an 1 of their techs sujested to antuate the IF signal, an got a IF antuator an it stop the frezing problem. now this was with a 920, have never ran into that problem agin, now the 922 that may not be a problem or it may, but most people don't have that large of a dish, so signal level is very important, but their is a point when their is to much also.

an the same thing aplies to TV sets when they are real close to the transmitter they will over load the tuner an have problems receiveing that station or other stations that may be week, same thing also goes true for satellite signal, but those receivers (commercal) will take more imput than what a residnetal receiver like a 920 or 922 will, it all come back to the agc an how it set an controlled in the receiver.

Good luck getting that dish will be a keeper, an a nice 1 at that.

Hey 1captain.

Hope you have a great new year too!

I have almost all but ruled out getting the big dish for myself. If someone here wants it, I'll try and claim it for them.

Right now I am more interested in pursuing a fixed dish solution for the entire arc for both C and Ku.

 

[linuxman]

Hey Cadsulfide,

I am pretty sure I understand the concepts of the 8X1 un-committed and committed diseqc switches. I also have a pretty good grasp of how 22Khz switches work.

The part I don't have a good grasp on is how to get the signal from all those lnbfs to multiple receivers so they don't interfere with each other.

 

[voomvoom]

Fred, I use 8 @ 4x4 multi-switches (Zinwell), going to 4 @ 8x1 uncommitted diseqc switches (Digiwave). It works great! I'm currently only using 7 of the multi-switches in the mix, I have room for two more twin lnb's (lnbf's) and as many dishes as they might need? I use a dual C-Band feedhorn with 2 @ Norsat 8115 lnb's, and a P* 1m with it's original V/H lnb, and 10 @ twin JSC322 lnbf's, on a T90 and 2 more on a 90cm dish. I originally used the Emp-Centauri 8x1 switches, but had lots of problems with them. I won't recommend them.
I should also be able to put some 4x1 diseqc switches in front of the uncommitted switches and get up to 4 times as many lnb's envolved, using the same type switches. But, I don't currently see a need for that..... yet?

And I'm feeding a Pansat 9200HD and 3 @ Coolsat 5000's from this set up.

 

[linuxman]

Fred, I use 8 @ 4x4 multi-switches (Zinwell),

Ok, so these are standard 4X4 multi-switches (2 - 13v outputs, and 2 - 18v outputs of which 2 are 22Khz on, and 2 are 22Khz off)?

going to 4 @ 8x1 uncommitted diseqc switches (Digiwave).

I had read elsewhere here that you had good success with the Digiwave switches.

It works great! I'm currently only using 7 of the multi-switches in the mix, I have room for two more twin lnb's (lnbf's) and as many dishes as they might need? I use a dual C-Band feedhorn with 2 @ Norsat 8115 lnb's, and a P* 1m with it's original V/H lnb, and 10 @ twin JSC322 lnbf's, on a T90 and 2 more on a 90cm dish. I originally used the Emp-Centauri 8x1 switches, but had lots of problems with them. I won't recommend them.
I should also be able to put some 4x1 diseqc switches in front of the uncommitted switches and get up to 4 times as many lnb's envolved, using the same type switches. But, I don't currently see a need for that..... yet?

And I'm feeding a Pansat 9200HD and 3 @ Coolsat 5000's from this set up.

So how did you hook them all up?

You knew I would ask. HeHe

 

[Anole]

I use 8 @ 4x4 multi-switches (Zinwell), going to 4 @ 8x1 uncommitted diseqc switches (Digiwave).

Imagine this picture but with more 4x4 multiswitches, and the Digiwave 8x1 diseqcs instead of the little 4x1's.
And if you really needed more receivers, then I suppose the multi-switches could be 4x8's, instead!

I think the biggest problem with a custom switch array, is that some receivers won't talk through it properly.
The ones you have today might, but what about that next receiver you get? Will it?
The 4DTV's sure won't.

 

[linuxman]

Imagine this picture but with more 4x4 multiswitches, and the Digiwave 8x1 diseqcs instead of the little 4x1's.

Ok, I think I am starting to understand. I will have to stare at the picture and explanation for a while though.

So I would need to have dual output LNBFs. Standard single output LNBFs won't work for this scenario?

And if you really needed more receivers, then I suppose the multi-switches could be 4x8's, instead!

I think the biggest problem with a custom switch array, is that some receivers won't talk through it properly.
The ones you have today might, but what about that next receiver you get? Will it?
The 4DTV's sure won't.

The 4DTV's won't even be in this equation.

You are correct, the receivers would need to be Diseqc 1.1 compliant or as close to 1.1 compliant as possible.

 

[Anole]

gettin' 2°

Just thinking out loud here about how many C-Band dishes needed to cover most of the arc using fixed dishes and multiple C and/or C/Ku LNBFs.

1 - 72W AMC6 could be combined to get 74W H2 Ku as well.
2 - 87W AMC3, 89W G28, 91W G17 for C and Ku signals
3 - 95W G3, 97W G25, 99W G16 for C and Ku signals
4 - 101W AMC4, 103W AMC1, 105W for C and Ku signals
5 - 107.3W AnikF1 for C and what Ku is there
6 - 121W G23, 123W G18, 125W G14/AMC21 for C and Ku
7 - 127W G13, 129W G27, 131W AMC11 for C and Ku
8 - 133W G15, 135W AMC10, 137W AMC7, for C-Band

Assuming that you can get 3 satellites with 2 degrees of separation per Big Dish using 8 dishes one could get most of the arc with most of the English channels viewable from NA.

edit: looks like if you could use 1" dual-output LNBs, you could rule the world.
In some places ya might get 2" units to work. And, being larger, they might collect more signal.
But that's for Ku band; I don't think you can get C-band LNBF's that close together.

Here's what I got for some representative birds, given a 40.875" focal length for the Birdview:

a). 72° to 74° = -1.996" horiz, -0.57" vertical from first LNB to 2nd LNB
b). 91° to 93° = -2.28" horizontal, 0 " vertical
c). 101° 103° = - 2.139" horiz, +0.356" vertical
d). 101° 105° = -4.20" horizontal, +0.78" vertical
e). 135° 137° = -1.28" horizontal, +0.998" vertical

Your 10" Unimesh with 48.25" focal length would do a little bit better.

These caluclations were based on a nearby zip code of 63102, and I used the GeoSat Satellite Finder for basic numbers.

 

[voomvoom]

Ok, so these are standard 4X4 multi-switches (2 - 13v outputs, and 2 - 18v outputs of which 2 are 22Khz on, and 2 are 22Khz off)?

Yes

So how did you hook them all up?

You knew I would ask. HeHe

Of course I figured as much
basically it's fairly simple, using 1.1 diseqc commands

C-Band = 1 - 1 Off, 10' dish with dual feedhorn & 8115 Norsat's, the voltage is supplied by a 922 (4dtv)
129 = 1 - 1 On, 90cm dish with twin JSC322 ku lnbf
125 = 1 - 2 Off, 90cm dish with twin JSC322 ku lnbf
123 = 1 - 2 On, Primestar 1m with original V/H lnb
105 = 1 - 3 Off, T90 with twin JSC322 ku lnbf
101 = 1 - 3 On, T90 with twin JSC322 ku lnbf
97 = 1 - 4 Off, T90 with twin JSC322 ku lnbf
93 = 1 - 4 On, T90 with twin JSC322 ku lnbf
89 = 1 - 5 Off, T90 with twin JSC322 ku lnbf
87 = 1 - 5 On, T90 with twin JSC322 ku lnbf
83 = 1 - 6 Off, T90 with twin JSC322 ku lnbf
79 = 1 - 6 On, T90 with twin JSC322 ku lnbf
74 = 1 - 7 Off, T90 with twin JSC322 ku lnbf
72 = 1 - 7 On, T90 with twin JSC322 ku lnbf
my 8th multi-switch is empty at present
these same settings are used in both the Pansat 9200 & all 3 Coolsat 5000's

 

[Anole]

VoomVoom -

Wow, that's a nice setup! - :up
And I hope you got a wholesale price on all those JSC322's.
I just did a quick Google search, and found 'em from $16 to $30!

I know a while back we found the Digiwave 8x1 diseqc switches for under $20.
Haven't shopped 'em lately.

Was looking on the DMSI web site for something just now and found they now have an 8x1 diseqc.
Unfortunately, there are no specs on it, and neither Sadoun nor IvyStonePlace seem to list it.

Now if we can talk Linuxman into a T-90 (or two), he might free up all those 84e & 1m Primestars for customers! -

 

[linuxman]

edit: looks like if you could use 1" dual-output LNBs, you could rule the world.
In some places ya might get 2" units to work. And, being larger, they might collect more signal.
But that's for Ku band; I don't think you can get C-band LNBF's that close together.

Here's what I got for some representative birds, given a 40.875" focal length for the Birdview:

a). 72° to 74° = -1.996" horiz, -0.57" vertical from first LNB to 2nd LNB
b). 91° to 93° = -2.28" horizontal, 0 " vertical
c). 101° 103° = - 2.139" horiz, +0.356" vertical
d). 101° 105° = -4.20" horizontal, +0.78" vertical
e). 135° 137° = -1.28" horizontal, +0.998" vertical

Your 10" Unimesh with 48.25" focal length would do a little bit better.

These caluclations were based on a nearby zip code of 63102, and I used the GeoSat Satellite Finder for basic numbers.

I agree. I talked to Mike Kohl about the C-Band multi-LNBFs, and his suggestion was pretty much the same. You could only do two LNBFs with 2 degree spacing and that would need to be done on at least a 10 foot dish with a very flat F/D ratio like the Unimesh.

The most I could probably hope for is 3 or 4 fixed C-Band dishes with only 2 LNBFs each on them pointed at the most often viewed satellites. Of course they could be shared by all receivers.

Of course I figured as much
basically it's fairly simple, using 1.1 diseqc commands

C-Band = 1 - 1 Off, 10' dish with dual feedhorn & 8115 Norsat's, the voltage is supplied by a 922 (4dtv)
129 = 1 - 1 On, 90cm dish with twin JSC322 ku lnbf
125 = 1 - 2 Off, 90cm dish with twin JSC322 ku lnbf
123 = 1 - 2 On, Primestar 1m with original V/H lnb
105 = 1 - 3 Off, T90 with twin JSC322 ku lnbf
101 = 1 - 3 On, T90 with twin JSC322 ku lnbf
97 = 1 - 4 Off, T90 with twin JSC322 ku lnbf
93 = 1 - 4 On, T90 with twin JSC322 ku lnbf
89 = 1 - 5 Off, T90 with twin JSC322 ku lnbf
87 = 1 - 5 On, T90 with twin JSC322 ku lnbf
83 = 1 - 6 Off, T90 with twin JSC322 ku lnbf
79 = 1 - 6 On, T90 with twin JSC322 ku lnbf
74 = 1 - 7 Off, T90 with twin JSC322 ku lnbf
72 = 1 - 7 On, T90 with twin JSC322 ku lnbf
my 8th multi-switch is empty at present
these same settings are used in both the Pansat 9200 & all 3 Coolsat 5000's

Thanks Al!!

I am starting to get the picture.

You have both been very helpful. I can see where a lot of money can get tied up real quick just for convenience sake.

But I think in the long run it might be worth it.

 

[voomvoom]

The Digiwave's came from the Cyberstore @ $20 a piece. The JSC's came from DMSI through PSB's store. I ordered a dozen and paid about $180 (I think?). I got the Norsat's @ Rick's Satellite. Don't remember what I gave for them, it's been a while. I just got the Digiwaves, and I like them.

 

[Anole]

Well, I think VoomVoom has a more reasonable requirement.
Probably has only the one 4DTV receiver.
And apparently just the one C-band dish to move.

You have how many 4D's?
None of them are going to talk to fixed C-band dishes, unless THEY are slaved to some other receiver.
Mostly, 'cause I don't think they have a mechanism to choose which dish they talk to.
I think once you solve that problem, then the rest of the problems will be much simpler.

On another note, how about putting three LNBF's on a BUD?
If you recall a recent thread by Iceberg, he did one LNBF at the focus, and one LNBF off to just one side.
That was his six-foot Fortec Star dish.
I forget the spacing, but you could probably manage 4° .
Try rearanging your bird-list a bit, and see if two dishes, with 4° birds, covering the same part of the sky, would help the problem.
In other words, get every other bird on one dish, and the remaining sats on the 2nd.

 

[linuxman]

Well, I think VoomVoom has a more reasonable requirement.
Probably has only the one 4DTV receiver.
And apparently just the one C-band dish to move.

You have how many 4D's?
None of them are going to talk to fixed C-band dishes, unless THEY are slaved to some other receiver.
Mostly, 'cause I don't think they have a mechanism to choose which dish they talk to.
I think once you solve that problem, then the rest of the problems will be much simpler.

As I wrote above, the 4DTV receivers I have will each have their own separate dish to satisfy their needs and won't be part of the equation.

On another note, how about putting three LNBF's on a BUD?
If you recall a recent thread by Iceberg, he did one LNBF at the focus, and one LNBF off to just one side.
That was his six-foot Fortec Star dish.
I forget the spacing, but you could probably manage 4° .
Try rearanging your bird-list a bit, and see if two dishes, with 4° birds, covering the same part of the sky, would help the problem.
In other words, get every other bird on one dish, and the remaining sats on the 2nd.

from what I posted a couple of posts back: Post #31
I agree. I talked to Mike Kohl about the C-Band multi-LNBFs, and his suggestion was pretty much the same. You could only do two LNBFs with 2 degree spacing and that would need to be done on at least a 10 foot dish with a very flat F/D ratio like the Unimesh.

The most I could probably hope for is 3 or 4 fixed C-Band dishes with only 2 LNBFs each on them pointed at the most often viewed satellites. Of course they could be shared by all receivers.

 

[voomvoom]

Well, I think VoomVoom has a more reasonable requirement.
Probably has only the one 4DTV receiver.
And apparently just the one C-band dish to move.

Yes, I have the Pansat 9200 in the same room as the 922 (4dtv) and use the 4dtv to move the dish. Any of the DVB receivers can view any of the ku sats and whatever the C-Band happens to be pointing to.
The Norsats each have a 2x1 HF splitter with one port power pass and the power pass goes to the 4dtv receiver, the other port goes to the V/H ports of the 1st multi-switch and set to 1-1 Off in the receivers.

 

[Cadsulfide]

Hey Cadsulfide,

I am pretty sure I understand the concepts of the 8X1 un-committed and committed diseqc switches. I also have a pretty good grasp of how 22Khz switches work.

The part I don't have a good grasp on is how to get the signal from all those lnbfs to multiple receivers so they don't interfere with each other.

Linuxman;

I wasn't trying to kick sand....sorry.

I have four coax feeds from the house to the array, and have each reciever modulated to a different channel IE Merc II to ch4, DP311 to Ch24, Neusat to Ch36, piped throughout the house. I'm using Powermid remote extenders at each tv, and planning to get a couple of learning remotes to reduce that clutter. You could get the whole arc on a few centralized recievers with simpler switch wiring.

 

[linuxman]

Linuxman;

I wasn't trying to kick sand....sorry.

I have four coax feeds from the house to the array, and have each reciever modulated to a different channel IE Merc II to ch4, DP311 to Ch24, Neusat to Ch36, piped throughout the house. I'm using Powermid remote extenders at each tv, and planning to get a couple of learning remotes to reduce that clutter. You could get the whole arc on a few centralized recievers with simpler switch wiring.

No Problem!

I found your drawing in your thread in the FTA Shack. It is very nice and quite extensive.

Thanks for sharing.

 

[FTA hunter]

i have the same dish but dont have the lnb holder please could give me some pictures of the lnb holder