How to improve indoor dish reception issues

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newbie08

Member
My Satellite Setup
raven sky minidish, internally mounted behind window
My Location
Brighton
I have a Raven sky Mk4 Satellite Mini Dish (oval 60cm) with Quad LNB (Zinwell J4S) pointed out the window connected to a sky HD box. I receive some channels perfectly but others have no signal and some others are pixelated and unwatchable. I get about 30% signal quality according to the sky box.

Just wondering if anybody has any suggestions to improve the signal, a bigger dish is not possible due to the window size. I am considering upgrading the LNB or perhaps trying the Multimo cassegraine twin LNB. A search on this forum and others concentrates on whether a signal can be received not how to improve it. Any suggestions appreciated.
 
Have you tried fine tuning the alignment of the dish and the LNB skew? Aside from that, not convinced that there is much you can do, it may be that the window is simply attenuating the signal too much
 
Ay.

There are those who suggests the U value of the glass can be important, and no doubt it's orientation relative to the dish, it's thickness and whether it is single, double or triple glazed will also be relevant (Of course, these latter factors are connected with the U value).
 
Try lowering the physical height of the dish, you may be losing alot of signal if the dish is too high as most of the signal will be blocked by the wall above the window.
 
Yes DD is quite correct you may be assuming the signal arrives perpendicular to the dish face but it does not, you need the dish lower than the window, see the picture below
 

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If it's double glazing then break out the inner pane.
 
Many thanks for the feedback,

I have fine tuned the dish and LNB skew and I have no doubt that the angle to the glass has an effect. In regard to lowering the physical height of the dish, I assume this means i would need to move the dish further back from the window to avoid the lower wall , I tried to slightly lower it in its current position and the signal cuts out. I have included a pic to show the setup.

However, assuming all things are installed and tuned as well as possible, would a better LNB result in better reception?
 

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newbie08 said:
However, assuming all things are installed and tuned as well as possible, would a better LNB result in better reception?
Click to expand...

To be frank, I suspect not. The problem is that you aren't actually delivering sufficient coherent signal to the LNB in the first place, so replacing it with one with a lower Noise Figure and higher Gain is almost an irrelevance.

In any event, what is "better" ?

That's posed rhetorically because headline parameters tend to refer only best performance over a small part of the relevant Band (ku band) and are difficult to assess and compare on a theoretical basis.

However, not to be a complete kill-joy, they are cheap as chips and most of us have at least one in a drawer somewhere than can be used as a spare or for practical experimentation - you've nothing much to lose by trying another one anyway.

Edit #1: Nice view of the oggin, by the way!

Edit #2: As it's a "Sky" dish as opposed to a proper one, your choice of LNBs is pretty restricted - and there isn't much to choose between them from either a theoretical or a practical standpoint.
 
Probably a completely stupid suggestion, but can you not open the window to see how much improvement you would get? That way at least you would satisfy yourself that it was the glazing that was causing the problem not a misalignment/lnb issue. Or is it not an opening window? Nice tripod by the way!

@Tivù : Thank you for 'oggin'. I looked it up thinking it was an archaic term for window frame, but no. It's now gone into my mental Scrabble dictionary.
 
Sorry, Pete - force of habit. 'twas what we called the sick-making ether when I was serving in the Andrew (Pete leans once more towards his Learning Resources.................... )
 
You could always try mounting the dish upside down, then you could drop it slightly and get a little closer to the window, works well for internal installations.
 
Tivù said:
Sorry, Pete - force of habit. 'twas what we called the sick-making ether when I was serving in the Andrew (Pete leans once more towards his Learning Resources.................... )
Click to expand...

Not leans, but merely opens a new tab on Firefox and searches......Andrew Miller, 'a very zealous Press Gang Officer who pressed so many men into service that it was said he thought the Navy his own property'. Very interesting but completely off the original topic so the language lesson had better end here or else we'll have some admin bod clattering our 'lugholes....
 
rolfw said:
You could always try mounting the dish upside down, then you could drop it slightly and get a little closer to the window, works well for internal installations.
Click to expand...
If you do that, do you have to turn the LNB to skew it on the other side, or does that get cancelled out by it being upside down?
(Not sure I've explained this clearly enough)
 
The skew would not need to be adjusted if upside down.
 
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