Losing and regaining Channels

T

the frenchman

Member
My Satellite Setup
Thomson HD
My Location
Spain
I'm in Valencia Spain and very oddly at the moment seem to lose channels in the mornings only for them to reappear later in the day.
144 and 831 on Sky used to be nice and clear all through the day but now no signal up until 6-7 pm all of the CBS channels from 142-148 have gone completely. No big loss really,but does it point to an lnb fail or a positioning problem?
 
lot of things can go wrong
strong sunshine
dish alignment
problem with lnb
old or long cable
loose connection
growing tree
 
Quest HD (144) is on 11426V, as there is also a transponder on 11426H, skew needs to be perfect to prevent interference from the horizontal TP.

As your issue corresponds with daylight it may be worth placing something over the LNB body to shade it from the sun.
 
Gladstones said:
lot of things can go wrong
strong sunshine
dish alignment
problem with lnb
old or long cable
loose connection
growing tree
Click to expand...
Very obviously I have no expertise but I always thought that if you didn't have alignment you didn't get channels full stop and if an lnb was on its way out you'd lose channels never to return. Think I'll try a new lnb and try to find a way to shield it from the sun. Whoever thought of making the best lnb for Spanish reception black...
 
ozumo said:
Quest HD (144) is on 11426V, as there is also a transponder on 11426H, skew needs to be perfect to prevent interference from the horizontal TP.

As your issue corresponds with daylight it may be worth placing something over the LNB body to shade it from the sun.
Click to expand...
I'll try shading it in some way. Just thought it was odd that it's changing by the month. At one time you could always get Quest+ when Quest was missing,now they both go missing until about 6pm.
 
During strong sunshine signal gets weaker
If your dish is slightly out
Lnb is cooked
Quality of the cable is not good
All contribute in less signal getting to receiver
Makes the channels disappear

you can easily monitor the signal through your receiver
 
Sometimes I think I am going to mark reception levels on the position map and come to some conclusion but I never get around to it.
 

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Gladstones said:
During strong sunshine signal gets weaker
If your dish is slightly out
Lnb is cooked
Quality of the cable is not good
All contribute in less signal getting to receiver
Makes the channels disappear

you can easily monitor the signal through your receiver
Click to expand...
Cable is good and short run,most likely the lnb which is a few years old. Just imagined that once an lnb lost signals they'd stay lost. 244 and 832 are back now but heavily pixelated but in an hour they'll be a clear picture.
 
Hi all, I am in Benidorm and I also have experienced a loss of signal in some TP during the past 20 days.

Begining of June is always the same, the mouth with less signal.

I figured out in HD transmissions, ITV's and BBC HD Scotland pixelating at some hours.

But if you have lost SD transmissions your dish needs alignment
 
Fringe reception often fluctuates with channels weaker at certain times of day or year.

Certainly where lnb's bake in the midday sun you can find channels being lost for a few hours in the afternoon - thats the heat pushing the lnb internal crystals out of tolerance. If you are losing channels in the heat of the day and the lnb has been up more than a few years its worth changing it. In areas with extreme heat they need changing regularly.
 
Next time you loose channels during the day, go out and spray down the LNB with a garden hose for a few, if the channels come back, but fade out again you need a new LNB.

Also I don't know exactly where in Valencia you located, but dishpointer says that the signal from 28W comes in from a direction over the Ocean, what could be going on is a temperature inversion layer causing a signal fade, this inversion layer could act like a mirror**, causing a out of phase signal to mix with the true signal, this causes a drop in signal at the receive antenna. (the dish) Not much can be done about this type of problem except move the dish higher, or place something under the dish to block the reflected signal.

**Have you ever driven down a road and seen what looks like water standing on the road out in front of you, but get to that spot and it's dry, this is the mirrage effect of the Sun heating up the air and causing a reflection, the same can happen to RF signals at different times during the year.
 
The SD Discovery channels frequency is a particularly weak one in the Valencia area. CBSs are relatively stronger. (also keep an eye on the SD UK TV channels, like Dave, and ITV1 HDs). You need the right sized dish (you have not mentioned what size dish you have), aligned correctly, with a good LNB skewed correctly. Along with the fact that "Valencia" can mean city, province, or region, so it also depends where exactly you are in "Valencia"., as the signals can vary along the 200km that is Valencia. But generally in the Valencia province, a well aligned 110x120cm dish should keep those channels. But yes, 10+ hours in the 25+ sun can cook the LNB a bit.

"Whoever thought of making the best lnb for Spanish reception black..." - much better performing LNBs around than the Black range...like Inverto Red, or Home, and the old GI range were much better
 
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I have a 130cm famaval in Villajoyosa and 110cm famaval in Alicante.

In Alicante it is not big enough for HD transponders in summer time.
 
woborny said:
The SD Discovery channels frequency is a particularly weak one in the Valencia area. CBSs are relatively stronger. (also keep an eye on the SD UK TV channels, like Dave, and ITV1 HDs). You need the right sized dish (you have not mentioned what size dish you have), aligned correctly, with a good LNB skewed correctly. Along with the fact that "Valencia" can mean city, province, or region, so it also depends where exactly you are in "Valencia"., as the signals can vary along the 200km that is Valencia. But generally in the Valencia province, a well aligned 110x120cm dish should keep those channels. But yes, 10+ hours in the 25+ sun can cook the LNB a bit.

"Whoever thought of making the best lnb for Spanish reception black..." - much better performing LNBs around than the Black range...like Inverto Red, or Home, and the old GI range were much better
Click to expand...
I'm in Gandia.And unfortunately to get a clear line over next doors roof hardware my dish is in an exposed position so badly effected by any wind over 25 kph so maybe as well as a new lnb the positioning needs attention.
 
ozumo said:
Quest HD (144) is on 11426V, as there is also a transponder on 11426H, skew needs to be perfect to prevent interference from the horizontal TP.

As your issue corresponds with daylight it may be worth placing something over the LNB body to shade it from the sun.
Click to expand...
The use of a dedicated feed with a C120 flange can help with lowering the temperatures, by fitment of a thermosetting plastic spacer in between the two and M4 ceramic bolts (though skewer/kebab sticks made of bamboo can be used if careful).

With offset design LNBFs, the heating up of the feedhorn turns the whole device into a solar oven and temperatures in excess of 100 degree Celsius inside are not uncommon on the circuit board in sunny climates.
 
woborny said:
The SD Discovery channels frequency is a particularly weak one in the Valencia area. CBSs are relatively stronger. (also keep an eye on the SD UK TV channels, like Dave, and ITV1 HDs). You need the right sized dish (you have not mentioned what size dish you have), aligned correctly, with a good LNB skewed correctly. Along with the fact that "Valencia" can mean city, province, or region, so it also depends where exactly you are in "Valencia"., as the signals can vary along the 200km that is Valencia. But generally in the Valencia province, a well aligned 110x120cm dish should keep those channels. But yes, 10+ hours in the 25+ sun can cook the LNB a bit.

"Whoever thought of making the best lnb for Spanish reception black..." - much better performing LNBs around than the Black range...like Inverto Red, or Home, and the old GI range were much better
Click to expand...
Which model is the GI range?
 
the frenchman said:
Which model is the GI range?
Click to expand...
I dont think you can get the old GI range of LNB anymore (for about the last 3 years now!), and the new range are not as good so I would forget about them...
 
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