Freesat on Astra back running

[Nigel]

Very pleased to see thatFreesat is back and running with excellent picture and sound here on 120 cm dish

[montgolfiere]

This has been anticipated (see my previous Post) and, with regard to last Winter, should be the start of good reception until maybe March / April 2016.

[Allan]

This has been anticipated (see my previous Post) and, with regard to last Winter, should be the start of good reception until maybe March / April 2016.

Based on what we have seen so far, it certainly seems that a pattern has emerged. It would however be interesting to know what is behind the pattern.

I have seen all sorts of theories on the internet but none of them seem to stack up.

In the summer months when the air is generally clearer you would expect a stronger signal rather than the weaker signal that we have been getting.

My personal theory (and it's just a theory) is that SES Astra reduce the signal in summer because reception in their target area (UK) is easier.

Montgolfiere, I believe you keep signal strength readings, are the dates of the changes relatively consistent?

Anyone else got a theory?

[montgolfiere]

This year the Summer Signal Drop was both later (around 3/4 weeks) and generally less severe. I believe the Footprint was 'widened' by about '1 Dish Size' in the Region. eg. where i needed a 150cm. Gibby Dish, Chez moi, to give 99% reception, in fact a 125 Gibby with Feedhorn, gave nearly consistant reception. (I am discounting the variations in reception when 2g came into service, as teething troubles, unless of course the same pattern emerges next year).
Otherwise the Winter improvement has started when expected, at the beginning of September.
I am afraid i have no real info on why this happens.....SES are mighty Secretive!!

[russell]

Based on what we have seen so far, it certainly seems that a pattern has emerged. It would however be interesting to know what is behind the pattern.

I have seen all sorts of theories on the internet but none of them seem to stack up.

I agree. Unfortunately the data available is not very good.

Reception quality depends, not only on the received signal strength, but on the received signal to noise ratio and any interference such as cross talk to other signals.

Noise arrives from the background radiation from space, from solar radiation, from thermal radiation from the atmosphere and from the earth itself, and also from the LNB's noise figure or noise temperature. Any electrical component generates thermal noise.

Thermally generated noise power is directly proportional to the absolute temperature so will be greater in summer.

I can't find any data on signal strength variations over the year. I believe Dave (Montgolfiere) measures signal quality which is an undefined function of error rate and depends on signal strength, and noise amongst other factors. It is thus difficult to separate out all the variables and come to meaningful conclusions.

It might be helpful if someone could measure both signal strength and signal to noise ratio from a fixed site. Unfortunately I no longer have the equipment do do that.

Russell.