Scalar and LNB Focal Distance

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Babadem

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May 21, 2007
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I have the WSI $69.99 6ft special, and WSI ESX242 C-BAND LNB and I'm not getting the Escape on 99.0°W and REELZ on 91.0°W, but I was getting those on my 1.2M MiniBUD, even though the signals were kind of weak. The signals should have been stronger on the 6ft dish instead of not being there at all. Could it be that I have not placed the LNB at the right focal distance? For those with the WSI 6ft special and getting those channels that I mentioned, how far is the LNB placed on your Scalar? Is the WSI special a deep or shallow dish? I have attached pictures of where my LNB is placed on my scalar. Thanks, in advance for your contributions and solutions.
 

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F/D Ratio 0.38
Focus Length 682 mm

Do you have a signal meter? Reelz is unreal I get crazy good Sig Q from it. I would post a pic of mine but my 6 foot speical has been smashed twice now and is bent big time so I don't think it would help much since I can't get too much anymore with it.
 
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F/D Ratio 0.38
Focus Length 682 mm

Do you have a signal meter? Reelz is unreal I get crazy good Sig Q from it. I would post a pic of mine but my 6 foot speical has been smashed twice now and is bent big time so I don't think it would help much since I can't get too much anymore with it.

Yes, I have a signal meter the SATHero 200. The signal is there, but too weak to lock or display on the receiver (Micro HD).

F/D Ratio 0.38
= Should this correspond to the markings on the LNB?
Focus Length 682 mm = This would be the distance from scalar to the middle of the dish? Since the middle of the Dish has a hole, how can one measure it accurately?

Looking at the pictures do you think that the placement of the LNB on the scalar is fine or needs adjustment?
 
It looks like the feed throat is sticking out of the scalar a little too far for a .38 FD. Did you peak your signal by moving the feed in and out to settle on that position?

You can put anything across that hole (paper plate, piece of duct tape...?) and measure from it to about 1/8" or so into your feed throat to get your focal length.

Using the manufacturers FL and FD numbers assumes the dishes parabolic shape is at manufacturers spec.
 
F/D Ratio 0.38 = Should this correspond to the markings on the LNB?
Yes. I Just pulled out a new esx-242 and put it at .38 your's looks pretty darn close I can't tell from the picture angel.
photo (1).JPG
Have you played with the skew at all?
 
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Scalar and Feedhorn placement will certainly have an effect on Signal Quality, but shouldn't result in such drastic attenuation.

I agree, the skew setting is the most likely cause.
 
Yes. I Just pulled out a new esx-242 and put it at .38 your's looks pretty darn close I can't tell from the picture angel.
View attachment 81807
Have you played with the skew at all?
Since it's a motorized setup, I placed the zero "0" skew marking on the LNB at 9 O'clock and this was done at the highest point of the dish which is 71.03. I will look at the skew and the F/D again and see what I come up with.
 
Scalar and Feedhorn placement will certainly have an effect on Signal Quality, but shouldn't result in such drastic attenuation.

I agree, the skew setting is the most likely cause.

I will look more closely at your suggestion. So would you categories this as a shallow or deep dish based on the F/D of 38 and focal length of 682mm?
 
It looks like the feed throat is sticking out of the scalar a little too far for a .38 FD. Did you peak your signal by moving the feed in and out to settle on that position?

You can put anything across that hole (paper plate, piece of duct tape...?) and measure from it to about 1/8" or so into your feed throat to get your focal length.

Using the manufacturers FL and FD numbers assumes the dishes parabolic shape is at manufacturers spec.

Thanks for the tip!
 
Even though my dish is on the roof, I can get it down to where I can look directly into the feedhorn. Other people go a few degrees off one way or the other, but I line my vertical pickup to be directly vertical when the dish is at zenith. You would mark the scalar at the bottom exactly where vertical is, and if you can't see inside of your lnb like I can, you mark the outside of the lnb where the vertical probe is.

I say that because I get Reelz fine with that setting
 
Even though my dish is on the roof, I can get it down to where I can look directly into the feedhorn. Other people go a few degrees off one way or the other, but I line my vertical pickup to be directly vertical when the dish is at zenith. You would mark the scalar at the bottom exactly where vertical is, and if you can't see inside of your lnb like I can, you mark the outside of the lnb where the vertical probe is.

I say that because I get Reelz fine with that setting

I think from my varied results in the past that this could probably be the truth , seems each lnbf is a bit different on its alignment . making the probes align up with v being vertical and H being horizontal would probably place the 0 at 12 oclock could be a quick fix / test
 
Realignment of the skew and moving the F/D to 38 from about 40+ did it! I can now get Reelz at 68% quality, and Escapes comes in but bounces between 10% to 25% quality. Thank you all for your help!
 
Realignment of the skew and moving the F/D to 38 from about 40+ did it! I can now get Reelz at 68% quality, and Escapes comes in but bounces between 10% to 25% quality. Thank you all for your help!

That's great news good job for not just giving up. :)

Reelz is an awesome channel I enjoy it very much.
 
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