URGENT!: C Band Reception at Very Low Angle of Elevation

[Boni]

Hi

Has anyone experienced receiving c band signals at very low elevation angles

In my case I have a prime focus c band dish of 2.4m..I am located in Mauritius. I have tested reception of NSS7. The elevation angle HERE is of 0.9 Degree.

Results are as follows: signal strong for few minutes then fades completely then back.

Is it a case of interference or the scintillation effect due to troposphere.

Thanks

 

[Montafon Guy]

Hello Boni,

in this German Forum: _http://www.satclub-thueringen.de - they talk at the moment about the same fading by receiving 90° east in Europe ...

Maybe you ask there?


Regards Montafon Guy!

PS: which Beams from NSS7 can you receive?

 

[Turok]

what kind of motor do you have?

 

[patmos]

Hi Boni. I may know you but read this thread _http://www.vetrun.com/forums/showthread.php?t=7585. May be a bigger dish but this will amplify ground noise also.

 

[Zorba]

In Cyprus we get pas4,the african multichoice sat at 68e which is on C-band at a low angle. We do get problems with interference which we think comes from radars near the coast.Areas where the sea is not visible do not have problems.Apparently the C band frequencies are close to the radar frequencies. We also suspect mobile telephone repeater masts near by. If you connect a spectrum analyser to your dish you might see the spokes come and go on a regular cycle.

 

[Turok]

in the meantime i got response,from people in germany ,that lives in wimax areas,and the told,me that the get the best results with norsat cband lnbs from usa,looks like the are better protected,from outside signals then the other brands,
i cant test this,because,i have no other signals here!

i could imagine,that it would help,trying to make a selfmade protection cap for the cband lnb
made by lead,then you could minimeize,the interference signal to a lower level!

at the moment,some transponders are weaker then 2 month ago on 68,5 east in cband,my blindscan shows me around 155 tv channels where found
2,40m is in europe to small to get all!

the satelite is damage on one solar panal now,and lost power 25% hope that the bird soon will be replaced,but when the will use cband spotbeams,the funny games,receiving,weak signals from far away,are then over!

 

[Zorba]

I did not know that. But we get less than 100 channels here on 68.5e average 2m dish. only for the multchoice africa sports package,and some indian channels

 

[patmos]

the satelite is damage on one solar panal now,and lost power 25% hope that the bird soon will be replaced,but when the will use cband spotbeams,the funny games,receiving,weak signals from far away,are then over!

Is that true Turok? Do You mean PAS 7 or PAS 10 that is damaged. I never heard that. I was going to align one 2.4 m on it here.Reception is good here as reported by sat enthusiasts but it is a very tricky satellite. I have a dish on arc from AB3(5W) to Measat(91.5E). All satellites came ok except PAS7/10 which is always weaker. That's why I'm going for a separate dish.

 

[ralphmagno]

hello to all.
telstar 10 is at 76.5 east and has c band reception
the footprint shows 1.4 meter should be on i will probally
a 1.8 meter dish for this one.
HBO asia transmitts on this bird on tp9a on 3.960 ghz.
is the LNB for c band standard in asia as for europe??
is the lo all the same freq.
as we know ku band usa and ku band europe use different lo as well as circular pol.
they are using digicipher and old encryption system.

thanks
ralph

 

[Channel Hopper]

Hi

Has anyone experienced receiving c band signals at very low elevation angles

In my case I have a prime focus c band dish of 2.4m..I am located in Mauritius. I have tested reception of NSS7. The elevation angle HERE is of 0.9 Degree.

Results are as follows: signal strong for few minutes then fades completely then back.

Is it a case of interference or the scintillation effect due to troposphere.

Thanks

Yes, but no lower than 4 degrees. Noise from the ground, and the longer path of signal means you are most likely seeing noise only (mixed with some terrestrial signals on an intermediate frequency.)

You may have to move location.

 

[deepbluesky]

Fading is also an issue at 40.73N/22.60E aiming at 100.5E with <0.5°. 4148V comes and goes with 2.30m+wings=3.10m Famaval. Even 93.5E with 5.7° elevation shows this behaviour in Ku-Band but in this case it's more likely that weak signal causes it.

 

[IanW]

Boni,

Spot on. Scintillation, lots of atmosphere, ionosphere. Not to mention ground noise.

IanW.

 

[krithika]

Fading is also an issue at 40.73N/22.60E aiming at 100.5E with <0.5°. 4148V comes and goes with 2.30m+wings=3.10m Famaval. Even 93.5E with 5.7° elevation shows this behaviour in Ku-Band but in this case it's more likely that weak signal causes it.

Wings? What is that?

 

[Channel Hopper]

Wings? What is that?

Additional panels/petals, to increase the size of dish.

 

[deepbluesky]

But the wings are also from Famaval made for this particular dish: _http://www.famaval.pt/en/tiki-index.php?page=antenas_310

 

[BombedOne]

To cut off wimax and radar signal interference, you have to install special feedhorn on generic C band LNB. I have photos of it somewhere, can post if there's interest in it.

 

[paul682]

hi my friend BONI!

for my personal experience

the fading effects on so lower elevation is a normal thing!

nothing to do with radar or wi max

i am in ITALY central

where both YAMAL 90 east and MEASAT are very low in elevation

at my QTH i have yamal at elev. approx 1,00

MEASAT at elev 0,19

WHEN I PUT the c band signals

like 3876 V 12525

in some moments i see clearly pictures with a good signal margin

after 1 minute all disappear completely!!!!

for my big surprise in the first moments

after another minute all is bAck again

so your test at so low elevation with this phenomenon

is normal dont worry!

i hope to solve your dubts

cheers from ITALY

 

[Montafon Guy]

To cut off wimax and radar signal interference, you have to install special feedhorn on generic C band LNB. I have photos of it somewhere, can post if there's interest in it.

Hello BombedOne,

yes please post the photos - im very interested!



Regards Montafon Guy!

 

[Finnsat]

Has anyone experienced receiving c band signals at very low elevation angles

Yes, in analogue days from Asiasat2 which was received in Eastern Finland with very low elevation < 0,2 degrees.

Analogue "CCTV", RTP Internacional and Panda Shopping Network, but which were quite unstable signal. Best results when clear sky without any clouds and winter 25-35 celcius degrees below zero. Reception location was on a hill with without any obstacles (just cultivated fields and frozen lake)

Digital transponders were impossible to lock. In summertime analogue was impossible too.

Any Russians here? Can you receive Asiasat2 in St. Petersburg or in Carelia? How strong is it in Moscow?