Signal Quality

[admin_exported]

Hi, Just installed a Quad Lnb ready for my Humax Pvr. I checked the signal strength on my sky box which was 85% to 90%, but the signal quality is only at 50% any ideas how to increase the signal quality.

Thank you and a Happy Christmas.

 

[Dave_]

that's a big decrease in sq, are you sure you havn't knocked the dish out of alignment...

would suggest that the dish needs to be re-aligned/fine tuned.which requires a sat meter, and ideally should be done anyway when changing an lnb, but i appreciate that if your changing it yourself it's not alway's an option

 

[Alsone]

I agree with Daveh, sounds like its misaligned now.

Also, have you dialed in the required amount of Skew? Skew, is not supposed to be that vital but the more alligned it is the better the quality. For my location Skew is minus 12.5 degrees - thats a clockwise turn of 12.5 degrees clockwise as you're facing the dish.

For the exact alignment details for your house, this site is invaluable: http://www.dishpointer.com/

That said, if you've still got 50% quality, you dish is only very marginally out - could only be a millimetre or two in one plane.

Have you also checked you have the right LNB fitted? I believe Sky mini-dishes use a different LNB to full size dishes.

 

[Anonymous]

Hi, Thank you daveh75 and Alsone. Reference the dish alignment I hav`nt touched the dish at all it`s well secured but I did notice there was a spirit level on the dish what is this for any ideas?

 

[Dave_]

ignore that spirit level on the arm, it was supposed to help aid installation, but in reality is useless.

well if your absolutely sure the dish is rock solid and hasn't moved, then check the skew! although it doesn't usually affect the signal to the extent where talking here tbh, but something is amiss somewhere.

on the lnb there should be some numbers marked in degrees with a little marker/pointer(either on top or bottom of lnb dependent on lnb make/type),which you can adjust by rotating the lnb!

if you check the site alsone linked to it should tell you the correct skew needed for your location you can then adjust it accordingly.

it's also worth mentioning i have seen sky boxes working perfectly ok with signal as low as 25%, but obviously the higher you can get it the better,

 

[Anonymous]

Hi daveh75, Ive gone to the link ant the read out I have is ( Elevation 22.9`

Azimuth ( true ) 142.8`

Azimuth ( magn ) 146.1`

Lnb skew - 13.8`

Over to you daveh75 if you can make any sence of this.

Thank you for your input

 

[Alsone]

Azimuth (Mag) is the compas bearing from North. So if you set the Direction of Travel Arrow on the compass base to 146.1 degrees (twist the degree dial on the top of the compass so it aligns with the Direction of Travel Arrow on the compass base at 146.1), and then turn the compass so the needle is pointing north, the Direction of Travel Arrow on the compass should be pointing at the satelite.

Elevation is self explanatory, its the amount you turn the dish up relative to the horizon.

LNB Skew is the amount you turn the LNB off the vertical plane. If its minus then you turn it to the right ie clockwise as you're facing the dish.

To be honest, you really need a sat meter to make adjustments. A compass bearing on gives a rough starting point and with 50% quality your dish isn't far out. Resetting it from the compass in your case is likely to result in a total loss of signal as it will be too course.

Personally, I'd start with the LNB. Many have a scale marked on the top in degrees that will allow you to twist the LNB the required amount out vertical using the scale. Start with that.

If that doesn't work, the you're going to need a sat meter and have to use that to check elevation and then azimuth (direction). Personally I'd always check elevation 1st because once you slack the main pole brackets off to adjust direction the dish will sag downwards so both elevation and direction will be affected making it very difficult to set either.

Adjustments are very fine and although sat meter tone should be used to judge alignement up the ladder, ultimately you need to keep checking the signal quality on the tv by going down and checking the quality reading. Its quality not strength that matters.

When setting up go into the manual tuning menu and choose the transponder recommended in the Freesat manual for tuning (change it back to all later). Doing this will stop the box pulsing as it goes through the list. If you allow it to pulse, the power to the meter will be intermittent and the meter all over the place.

If in doubt, you could always call in a professional but maybe not the same people who fitted the dish originally unless you're absolutely sure it is slippage and not inaccuarte set up to start with.

 

[Dave_]

can't really add anything to alsone's comprehensive instructions (

alsone),other than start with the scew adjustment as alsone suggested as this should be the easiest to adjust assuming you have a sky mini dish as the lnb for these type dishes will almost definately have the scew adjustment marking's on them.

 

[Anonymous]

To Alsone & daveh75,

Well chaps I got the ladders out this morning and worked on the sky signal strength and quality, doing a few adjustments as per alsone & daveh75 posts and I can report an increase in the signal strenght to 90% also an increase in the signal quality to 70%an increase of 20% all this is down to you good guys.

A big thanks to you both for your input. Can not wait to see bbc high def when my Freesat Pvr arrives.

Once again thanks a Happy Christmas to you both.

 

[Alsone]

Glad to be of assistance.

If everythings OK now, then leave it as it is. If it isn't then adjust for more quality. As said above, signal strength isn't very important with satelite, its more about quality than strength. eg. 100 % signal but 40% quality will be a poor picture. However 100% quality and 40% strength will be an excellent picture. In reality, strength is probably never going to fall to anything like 40%, with my larger dish I can literally point it anywhere in the Eastern sky, including completely off all the satelites and below the horizon and still register 80% strength!!! I have 0% quality however! The rule is though adjust for quality not strength and you won't go far wrong.

If you need to make further adjustments but can't get improvement then get something like a Chess meter. They cost around £14 and whilst not brilliant in the quality department, the fact that they have adjustable sensitivity is enough to help you get an accurate lock. They measure strength alone but by turning the sensitivity progressively down and re-adjusting for strength, you can get quality by fine tuning to the alignment to such a degree that its a good indicator of perfect direction and thus quality also. Cross referencing it with the Humax Quality reading will allow accurate alignment even for such a cheap meter.

 

[Anonymous]

J J:

Hi, Just installed a Quad Lnb ready for my Humax Pvr. I checked the signal strength on my sky box which was 85% to 90%, but the signal quality is only at 50% any ideas how to increase the signal quality.

Thank you and a Happy Christmas.

Changed your SINGLE LNB to a QUAD one .............?

1/ Did you change your cable at the same time..............? if not give it a go ............... using the best quality F100 Cable you can buy and make sure it has GOLD FOIL shielding NOT Aluminium.

Check out my friends web site :- http://www.satcure.co.uk/useful/index.html for more details etc.......... Old perished cables, crushed cables (especially where the end fittings are poorly installed, etc ...... can all cause signal degradation.

2/ Your QUAD LNB is heavier than a single, it can cause (Brewer's) droop on your LNB Arm ............... try using fishing line (from the base of the LNB to the top of your dish .............. will help support it on the correct plane.

Have a look at the FAQ section on the above site .................... you may get some pointes ............... and you can buy everything you need as well?

Good luck