MULTI LNB SETUP

[srinivas33]

Here you should not only consider a single distance, you require three coordinates.

The above simulation gives your depth coordinate(which is negligible but try it)

the remaining two above figures gives you the other two coordinates.

I think your metal strip for holding lnb is not of enough length, make a larger strip.

 

[srinivas33]

"as per your this pic and above explanation distance between asiasat3s and insat 4a lnb is 38.5cm. i have also tried at this distance but could not get any signal but i am receiving siganal at just 20cm."


1.Confirm that you are aligned to Insat 4A(check whether you got all transponders), check in your android app.
After that check where is asiasat3s in the sky at your location, then place your second lnb in the path of mirror image signal line of asiasat3s with Insat 4A as the mirror plane.

2.Are you adjusting the second LNB through diseqc switch or directly?
Connect the second Lnb directly to STB(perform these after you completed above step) and then find the signal.

 

[riteish]

I have aligned center lnb to Insat4A and I have received all the transpoder of insat4a with good signal quality now my aim is to add 8 lnb to this set up and for that I have started with asiast3s. I also trying Multifeed android app to do the same but not understanding the calcualtion from this app. while adjusting dish i am not using diSEqc switch.

 

[riteish]

srinivas33:-
"After that check where is asiasat3s in the sky at your location, then place your second lnb in the path of mirror image signal line of asiasat3s with Insat 4A as the mirror plane."

will you please explain this point graphically!

 

[srinivas33]

I have aligned center lnb to Insat4A and I have received all the transpoder of insat4a with good signal quality now my aim is to add 8 lnb to this set up and for that I have started with asiast3s. I also trying Multifeed android app to do the same but not understanding the calcualtion from this app. while adjusting dish i am not using diSEqc switch.

use dishpointer app, it shows you satellites through the camera in the sky based on GPS location data and using the orientation sensors like gyroscope, accelerometer, etc.

After installing it and working, move upstairs and switch on this app and see directly through camera where is asiasat 3s and also check whether you aligned to insat 4a, you will find that asiasat3s is located to the left of Insat 4A, and also the elevation of asiasat3s less than Insat 4A.

now assume a straight line from asiasat3s to the center of your dish, now this straight line gets reflected by the dish and this reflected ray will be symmetrical with respect to Insat 4A, i.e. the reflected ray will have elevation greater than Insat 4A and the reflected ray angle is equal to the incident angle.

This means you can keep the second lnb at 106 deg - 83 deg = 23 deg

now 83 deg - 23 deg = 60 deg

which satellite is at 60 deg?

Intelsat 904 is at 60 deg location, now keep the second lnb in the line of sight of intelsat 904 but elevation is not same as intelsat 904, keep the lnb in higher elevation than Insat 4a but it is equal to the how much elevation asiasat 3s is below the Insat-4A(comparing with Insat - 4A).
I will explain it with a sketch.

 

[riteish]

Here you should not only consider a single distance, you require three coordinates.

The above simulation gives your depth coordinate(which is negligible but try it)

the r emaining two above figures gives you the other two coordinates.

I think your metal strip for holding lnb is not of enough length, make a larger strip.

today i have made some larger length iron strip. and when i fix lnb on this strip at 38.5cm distance as per our one of friend dr30ma above explanation but i am not getting any signal at this point, so i put it at 20cm apart from insat-4a lnb then only i will be receiving signal but it is not stable one within very short moment of time it becomes 0. whats going wrong i dont know!

 

[srinivas33]

Try all possible motions, also interchange C+Ku Lnb with the Center LNB and check, all connections should be made after switching STB off.

When you are loosing signal? after inserting diseqc switch?

 

[dr30ma]

today i have made some larger length iron strip. and when i fix lnb on this strip at 38.5cm distance as per our one of friend dr30ma above explanation but i am not getting any signal at this point, so i put it at 20cm apart from insat-4a lnb then only i will be receiving signal but it is not stable one within very short moment of time it becomes 0. whats going wrong i dont know!

1st try to catch 100.5 then move lnb to left side to catch 105
3660 V 27500 is strongest tps of 100.5

 

[giri photog]

rithesh brother,
both lnb you placed in wrong position you just note the pictures posted by dr.30ma. note where the naming of lnb facing and check where your naming of lnb facing. this a major factor in tuning. insat 4a is easy to get so try once again vertical and horizontal tuning. don't be confused do the job with patience. remember no shortcuts in satellite tuning only patience is the companion of success. srinivas and dr30 ma explained well. plz post the result too

 

[dr30ma]

Here is my 6 feet solid dish Multi LNB setup.

For me Distance calculation...

1*= 1.7 cm
from middle of LNB to Middle of LNB.

eg.100.5-83=17.5 17.5X1.7=29.75 cm