"Dale Parfitt" wrote in message
news:l3Sfd.5421$dW.482@trnddc08...

"Thierry" - wrote in message ...
Hi,

A question : how weak is a geostationnary satellite signal at the edge ?
..

Do the math- what is the minimum dish size required to receive the
signal
in the 50dB contour? If your contour is 10dB- you are 40 dB down. Dish
gain
goes up 6dB each time you double the diameter- so you need a dsih 128X the
diameter of the 50dB contour dish. to yield the same pix quality.

Fine ! (a way of speaking) it's a new information for me.
OK that a 100m dish is not really realistic, at least for an amateur :-((

But the problem is also : as I am very much "out" of the main beam (say 50°
off in longitude), can I receive some signal ?
I have thought that the beam was like a cone and outside there was no
receive at all.
But you seem to say that the decreasing of signal strength is more or less
constant with distance, there is not abrupt decreasing say below 0 dB
contour or so ? right ?
Or in other words is there a maximum distance or a longitude difference over
which there is no more signal ? none ?
For short all 'd be a question of receive dish diameter... (and visibility
of the sat.) ?

Thierry, ON4SKY


Dale W4OP

"Thierry" - wrote in message ...

"Dale Parfitt" wrote in message
news:l3Sfd.5421$dW.482@trnddc08...

"Thierry" - wrote in message ...
Hi,

A question : how weak is a geostationnary satellite signal at the edge
?
..

Do the math- what is the minimum dish size required to receive the
signal
in the 50dB contour? If your contour is 10dB- you are 40 dB down. Dish
gain
goes up 6dB each time you double the diameter- so you need a dsih 128X
the
diameter of the 50dB contour dish. to yield the same pix quality.

Fine ! (a way of speaking) it's a new information for me.
OK that a 100m dish is not really realistic, at least for an amateur :-((

But the problem is also : as I am very much "out" of the main beam (say
50°
off in longitude), can I receive some signal ?
I have thought that the beam was like a cone and outside there was no
receive at all.
But you seem to say that the decreasing of signal strength is more or less
constant with distance, there is not abrupt decreasing say below 0 dB
contour or so ? right ?
Or in other words is there a maximum distance or a longitude difference
over
which there is no more signal ? none ?
For short all 'd be a question of receive dish diameter... (and visibility
of the sat.) ?

Thierry, ON4SKY


Dale W4OP

They may also reuse the frequency.

Tam