How to Configure for a Stacked LNB?

[cyberham]

Today installed an inherited LNB on my fixed experimental dish. It's a Star Choice part number 150478 and is described as a California Amplifier linear popcan stacked single LNBF. It's working fine, but when I blind scan I receive all transponders on both polarities. How can I configure my receiver so the blind scans give correct results.

 

[cyberham]

Searching through this forum, I think I've learned I must blind scan Horizontal only first using LO of 11250 MHz, then blind scan again Vertical only using LO of 10750 MHz.

 

[cyberham]

http://www.satelliteguys.us/threads/145978-What-is-Single-Stack-LNB-Type

 

[catamount]

I knew you were going to try it some day,LOL

The horizontals are stacked 575 Mhz above vertical. Options:

Scan vertical only - 11700 - 12775

Scan 11700-12200 vertical, then 12200 -12775 horizontal

With these two methods, horizontal will be 575 above true frequency! Verticals will show correct frequency.

Create 2 ku lists for a satellite, i.e. ku 103 V 10750 and ku 103 H 10175

We have been waiting for years for receiver manufacturers to figure this out. The Micro HD was not able to implement this feature, unfortunatly!

Catamount

 

[cyberham]

This is good info. Unfortunately, my S9 cannot scan only one polarity at a time. It also can't scan a manually programmed range of frequencies. The microHD can do both. For limited use, this LNB is fine on a fixed dish for picking off a channel or two. I can only imagine the chaos resulting by blind scanning a satellite like Galaxy 19. 10175 is not a provided LO frequency on either of my receivers.

 

[primestar31]

This is good info. Unfortunately, my S9 cannot scan only one polarity at a time. It also can't scan a manually programmed range of frequencies. The microHD can do both. For limited use, this LNB is fine on a fixed dish for picking off a channel or two. I can only imagine the chaos resulting by blind scanning a satellite like Galaxy 19. 10175 is not a provided LO frequency on either of my receivers.

I sure hope not, as that's a typo and should be: "10750".

 

[cyberham]

To get correct frequencies, I could scan vertical 11700 to 12200 using LO of 10750 MHz. Then scan horizontal 12200 to 12700 using LO of 11250 MHz.... (?).

 

[Keith Brannen]

I sure hope not, as that's a typo and should be: "10750".

No, 10175 is correct. From my post on the above linked thread:

My Pansat 3500SD has a single stack, but it shows:
10750 V / 10175 H

Anyhow, I did use my stacked Star Choice LNB (dual LNB) at one time, and here are the notes I wrote on it. I cannot remember now if I used the single stack setting or not.

On a horizontal scan only, the vertical frequencies are 575 lower than actual, while the horizontal frequencies are correct. If the vertical is scanned then the vertical frequencies are correct and the horizontal are 575 higher than actual.

 

[Keith Brannen]

To get correct frequencies, I could scan vertical 11700 to 12200 using LO of 10750 MHz. Then scan horizontal 12200 to 12700 using LO of 11250 MHz.... (?).

To get horizontal you need to use a low of 10175, and scan 12200 to 12700 to get the correct frequency numbers. Are you sure to can't manually type in a LO on the MicroHD? I can on both my AZBox and on my old Pansat 3500SD.

 

[cyberham]

Then I can't display correct frequencies on horizontal with either S9 or microHD. There is no LO of 10175 and you can't manually enter an LO frequency.

 

[Tank]

cyberham
on the microHD there is an option for 10750/10175. scroll down in the lnb lo list and it will show STACKED (10750/10175) as an option

 

[cyberham]

I had seen those stacked settings and forgotten about them. I'm a little handicapped in testing now since my fixed dish happens to be on 121W which only has V transponders. When the weather warms, I can move the dish to a satellite with active V and H transponders. Interestingly, about the only Ku satellites available with strong transponders on both V and H are 87W and 97W neither of which may be viewable at the location of this dish (may be behind The Tree).

For now, when I scan the full range 11700~12750 using the 10750/10175 setting, the results show all V transponders on the correct frequency but wrongly labeled with H polarity. I get the same results if I only scan 11700~12200. If I only scan 12200~12750, I receive nothing.

So it seems the receiver sees nothing above 12200. As mentioned previously, if I use an LO of 10750 and scan 11700~12200, I receive all V transponders two times with one set labeled H and one set labeled V. A curious LNB.

 

[Keith Brannen]

There are a couple of Horizontal transponders on 121W, which, for me, are not quite as strong as the vertical transponder with the FTA channel you are getting. I have no idea whether they are available in your area or not. Anyhow, since you are not receiving any horizontal transponders, you might want to check the LNB by rotating it 90 degrees and see what scans in. The only reason I mention it is that one of my old SC stacked LNBs crapped out where the horizontal channels could no longer be received, and just the vertical worked. Of course, you may have already tested the LNB, but just in case you haven't it might be an idea to check.

 

[cyberham]

I think my LNB is broken like yours was. When I rotate it 90 degrees, I now receive a couple of new transponders. One is even a non-Dish HD tp. I think I may retire this LNB.

 

[catamount]

As mentioned previously, if I use an LO of 10750 and scan 11700~12200, I receive all V transponders two times with one set labeled H and one set labeled V. A curious LNB.

Yes, this is correct!

I requested the 10750/10175 setting for the micro HD request thread. Brian acknowledged later on that they couldn't get it to work. I don't know why they kept in in there. To get any horizontal TP's you have to scan 12200-12775, using Lof of 10750 (standard). It doesn't matter if they are labelled H or V , but giving them H is what they are, however 575 higher.

Catamount

 

[catamount]

pic

Here is a pic of mine pointed at 103 with about 20 degree funky skew applied!

 

[cyberham]

I've now installed my faithful DGL990D LNB on this dish again. That other one is too much trouble.

 

[Keith Brannen]

I think my LNB is broken like yours was. When I rotate it 90 degrees, I now receive a couple of new transponders. One is even a non-Dish HD tp. I think I may retire this LNB.

Mine was damaged by water/ice repeatedly getting in the outdoor switch it was connected to when it was on my SC dish for my sub. Spent a couple of times on winter nights up on a ladder with a hairdryer before it crapped out one of the LNBs. Bought a new SC LNB (quad output) after that, and never have had a switch outdoors since (all my switches for FTA are indoors). Did use the LNB (the other LNB on the dual satellite holder was fine) for a while, before buying a new SC LNB to replace it when I wanted both H and V on that LNB.