Picture breakup

WightWalker

New Member
I occasionally get picture breakup which is a band of random pixilated colours across any part of the screen. It might just happen once or twice a night but on other occasions it can occur every few seconds.

I first thought that this was when I was recording 2 programs whilst watching another and the heads couldn't necessarily keep up. But I then noticed that it happened when just viewing 1 program without any recording activity.

Signal strength is good on both LNBs.

Haven't noticed this when the Humax is connected to a different system.

Could it be a problem with the LNB or dish alignment?
 

Martin

Member
I get the same sometimes when we have heavy rain or a storm in the area, does not have to be raining here but storm clouds in the direction the dish is pointing will cause it. I am on the South Downs looking out over the channel and often a storm in the channel will do the same, sometimes the signal is lost completely. Signal is normally 100%
 
OP
W

WightWalker

New Member
Living on the Isle of Wight, we look directly across The Channel, so it could be that. I'll have to pay particular attention to the weather at the time it next occurs.
 

Mike2

Scrat
Living on the Isle of Wight, we look directly across The Channel, so it could be that. I'll have to pay particular attention to the weather at the time it next occurs.


I have had that a few times recently. It happened last night a couple of times and there was no rain about, as far as I know. My impression is that it has recently become more frequent. It's like a coloured snow effect in a strip across the screen? Not like the blocky freezing we generally get when the signal goes. Please tell me it's not those 4G phones...:mad:

In heavy rain, our signal can vanish completely. Also, when the LNB is covered in sticky snow the signal goes too. Once we lost it for several days when snow fell and then froze onto the dish and LNB. At times like this we switch to terrestrial TV for recording.
 

grahamlthompson

Well-Known Member
I have had that a few times recently. It happened last night a couple of times and there was no rain about, as far as I know. My impression is that it has recently become more frequent. It's like a coloured snow effect in a strip across the screen? Not like the blocky freezing we generally get when the signal goes. Please tell me it's not those 4G phones...:mad:

In heavy rain, our signal can vanish completely. Also, when the LNB is covered in sticky snow the signal goes too. Once we lost it for several days when snow fell and then froze onto the dish and LNB. At times like this we switch to terrestrial TV for recording.

Your dish is most likely not optimally aligned. The best solution is to go up one dish size and ensure the dish is optimally aligned. I never lose signal in heavy rain (60cm dish Midlands) and only once in heavy snow (my dish is low enough to brush off snow with a broom).

It's not 4G, wrong frequency.
 

Mike2

Scrat
Your dish is most likely not optimally aligned. The best solution is to go up one dish size and ensure the dish is optimally aligned. I never lose signal in heavy rain (60cm dish Midlands) and only once in heavy snow (my dish is low enough to brush off snow with a broom).

Strength is 90%, quality 100% at the moment, light rain, tuned to BBC1. Switching to BBC1 HD, it is 100/100. Is it worth trying to improve this?

Anyway, you are in Redditch, 1 degree further South than me. Less atmosphere to penetrate! :D
 

grahamlthompson

Well-Known Member
Strength is 90%, quality 100% at the moment, light rain, tuned to BBC1. Switching to BBC1 HD, it is 100/100. Is it worth trying to improve this?



Anyway, you are in Redditch, 1 degree further South than me. Less atmosphere to penetrate! :D

It's more down to beam intensity, a beam that concentrates all it's energy into a tight UK spot beam will have a much stronger field strength than a wide beam transponder.

Anything else changed recently, trees grown in the beam path ?. Your lnb may be getting tired, a new one may help. A local source of rf may be involved. Faulty boiler ignition for instance.

The new satellites 1F and 1E when it arrives should be very strong in the UK so may improve your signals anyway.

What size dish are you using ?

Is the receiver a Sky one, A Freesat one or a generic fta ? Some are more sensitive than others and will hang onto a poor signal more effectively than others. Not much point in posting signal strength unless we both have the same box, the indicated signals vary widely on the same dish. For instance most of my spot beam transponders indicate 100/100 on a Foxsat-hdr but only 70/80 on an old Sky box (this was used to align the HDD in the first place).

If you want I can take a straw poll of some transponders for comparison purposes.

BBC1 WM (10788 V) is currently 100/100. Light mist and overcast.

If you can get at the dish covering about half of the dish face with a wet towel will give a good clue how it will perform in poor weather conditions.
 

Mike2

Scrat
It's more down to beam intensity, a beam that concentrates all it's energy into a tight UK spot beam will have a much stronger field strength than a wide beam transponder.

Anything else changed recently, trees grown in the beam path ?. Your lnb may be getting tired, a new one may help. A local source of rf may be involved. Faulty boiler ignition for instance.

The new satellites 1F and 1E when it arrives should be very strong in the UK so may improve your signals anyway.

What size dish are you using ?

Is the receiver a Sky one, A Freesat one or a generic fta ? Some are more sensitive than others and will hang onto a poor signal more effectively than others. Not much point in posting signal strength unless we both have the same box, the indicated signals vary widely on the same dish. For instance most of my spot beam transponders indicate 100/100 on a Foxsat-hdr but only 70/80 on an old Sky box (this was used to align the HDD in the first place).

If you want I can take a straw poll of some transponders for comparison purposes.

BBC1 WM (10788 V) is currently 100/100. Light mist and overcast.

If you can get at the dish covering about half of the dish face with a wet towel will give a good clue how it will perform in poor weather conditions.

Thanks, Graham. I can get to the dish by climbing onto a flat roof. If the problem persists I may do that.

The dish is a standard ~14 year old Sky one and the receiver a Foxsat HDR of course. (See forum title!) I put a quad LNB in when I got the HDR, and, yes, that may need replacing. It is possible the dish has sagged a bit too. If anything, there is less vegetation in the way now, as a new neighbour cut all the trees back.

Maybe our local owl population use the dish as a perch?
 

grahamlthompson

Well-Known Member
I confess I was thinking of the little square ones.

Sky dishes are oval, always have been even the first Mk1 designs used for the analogue service from 19.2E. The square ones were a rival digital service that went bust years ago. I installed a Mk4 dish and lnb (total cost £20.00) for a neighbour and it works very well. The latest dishes are a bit larger in area than earlier ones.

Found the details after some research

http://en.wikipedia.org/wiki/Squarial
 

Mike2

Scrat
Sky dishes are oval, always have been even the first Mk1 designs used for the analogue service from 19.2E. The square ones were a rival digital service that went bust years ago. I installed a Mk4 dish and lnb (total cost £20.00) for a neighbour and it works very well. The latest dishes are a bit larger in area than earlier ones.

Found the details after some research

http://en.wikipedia.org/wiki/Squarial



http://www.amazon.co.uk/Satellite-Dish-H30D2-Flat-Antenna/dp/B00319C8W0

I see a Zone 2 Mk 4 dish and quad LNB costs only about £24, too. It's the alignment that puts me off.

http://www.amazon.co.uk/Systemsat-Zone-Satellite-Dish-Freesat/dp/B004YCFH9Y/
 

Mike2

Scrat


All very well, but I have to get the dish almost vertical, which I think I can do, then turn it in the right direction for an indeterminate number of current and future satellites. I then have to turn it slightly off-vertical so it points at the satellite at my latitude. Finally, I must rotate it slightly?

Anyway, there is something about new satellites coming online that are narrower beamed than the old ones: Astra 2E and 2G. Will that make the problems go away soon?
 

dandnsmith

Forum Supporter
Probably not. What the new ones will give is a tighter focus on the beam, but not noticeably more power at the receiving dish. If you have (already) reception problems, they may well get worse, and the best fix is a larger dish. As has been said earlier, a 'better' receiving apparatus can help, as can a better LNB.
 

Mike2

Scrat


Finally took the plunge and upgraded the dish as suggested. It took me longer than expected because I couldn't find my compass, but in the end I used the one in my phone. Also a satellite aligning app that kept pointing in the wrong direction until I fiddled with its settings.

It's a 60cm Mk4 Zone 2 thing. I finally got my optimal direction after a pan, tilt, then further pan, and I am pretty confident it is spot on as I was up there fiddling with it all morning. I now have 90% strength and 100% quality on BBC1 Yorkshire and 100/100 on BBC1 HD. This is exactly the same as I reported from the old dish in post #5! The freesat test channel has considerably lower strength, also some Welsh channel, but most are 90/100 or better.

So, have I wasted my time? I will check next time it rains heavily (Sunday?) and report back.
 

Mike2

Scrat
So, have I wasted my time? I will check next time it rains heavily (Sunday?) and report back.

Survived several torrential storms with no change in signal strength or quality. Thanks, guys, good suggestion! The next test is snow...

Am I supposed to be getting very different (but steady) signal strength on some channels?
 

grahamlthompson

Well-Known Member
Survived several torrential storms with no change in signal strength or quality. Thanks, guys, good suggestion! The next test is snow...

Am I supposed to be getting very different (but steady) signal strength on some channels?

Yes you will get different signal strengths from some channels. The channels carried on widebeam transponders spread the same sort of rf over a wider area so the field strength is inherently lower even in the middle of the footprint.

Snow is much like rain, unless it's the wrong sort :). Wet sticky snow if the wind direction is wrong and it covers the dish face will kill your signal dead. A broom with a long handle can work wonders ;)
 

Mike2

Scrat
Yes you will get different signal strengths from some channels. The channels carried on widebeam transponders spread the same sort of rf over a wider area so the field strength is inherently lower even in the middle of the footprint.

Snow is much like rain, unless it's the wrong sort :). Wet sticky snow if the wind direction is wrong and it covers the dish face will kill your signal dead. A broom with a long handle can work wonders ;)


Thanks again, Graham.
 
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