Technical solutions for the reception of satellite Insat 4B on the island of Taiwan in the KU band: PF 3.7m,
Invacom SNF-031,Fuji SSI-T20,f/D ratio,feedhorn,radiant diagram ...

• From: Mr.Rajendra N.
• To: Mr.Roman Dávid / roman.david@dxsatcs.com
• Sent: Tuesday, March 23, 2010 10:44 AM
• Subject: Insat 4B Ku Band
  
• State: Taipei - Taiwan

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• TEXT questions nr.1 :

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Dear Mr.Roman Dávid,
        
I have checked your website its really amzing updates you have. You deed really hard work there.
My name is Rajendra N. working on IPTV project in Taiwan.I have 3.7 meter Solid dish antenna, I try
to receive Insat 4B ku band signal here but i can not receive. I can receive C band perfectly here.
What kind of solution you have for me?

waiting for your reply
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• Insat 4B at 93.5°E elementary technical data : footprint & installation point
  

        Insat 4B at 93.5°E - 4B wide footprint : measurements at the center Taipei/Taiwan
                     geographical location : Latitude: 25.0911°_ Longitude: 121.5598°
                                       antenna tracking : AZ=231,5° and EL=47,1°

             Insat 4B-KU band : measuring point    Insat 4B-KU band : theoretical footprint
         
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• Answer to question nr. 1 :

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Dear Mr.Rajendra,
    
      Thank you for your message regarding reception from the satellite Insat 4B in Ku band  from position 93.5°E.
If I understand correctly you are not using a MESH or micro-mesh antenna because then you  would have tried to
receive totally unnecessary.I do not know what the Insat 4B satellite EIRP flow layering in East Asia for the KU band,
but the reception on the island of Taiwan is not guaranteed even if it is more likely than me to Slovakia with PF 3.7 m.
Please describe to me your complete satellite system such as what you use to process orthogonal waves in KU band,
will be best if you send me some photos from the antenna and LNB etc.You are using fixed or rotary system ? Have
you analyze the spectrum satellite Insat 4B you in Taiwan ?You have only failed to capture the satellite Insat 4B in
Taiwan or any fans who have already captured Insat 4B?
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• sent photo presentation :

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• TEXT questions nr.2 :

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Hello Mr. Roman Dávid,
 
Thanks for your prompt and quick reply.

I am using 3.7 meter solid dish (prime focus) attached pictures.LNB is universal Ku Band LNB (Lo.9750, Hi. 10600)
Today i try to receive NSS 6 Northeast beam and its successfully. But India beam and even south Asia beam I can
not receive.And also signal level is not satisfactory in 3.7 meter dish.Its is really better in 1.2 meter dish.
Can i need Offset dish for Ku band ? I will send you spectrum graph soon but no activity in India beam.
waiting for your reply
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• sent photo presentation :

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• Answer to question nr. 2 :

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Dear Mr.Rajendra ,
 
 Thank you for your reply and photos....
 
 although I can not guarantee the availability of signal from satellites Insat 4B, in place of reception on the island
of Taiwan , but I can advise you as follows :
 
1,I would completely remake the optics and the mounting of the converter, because I'm not sure of its location in the
antenna focal !  It is possible that the converter is not in the exact focal point of the antenna but only in the side lobe
of radiant diagram !!! - the problem I have dealt several times around the world . /minus MER=5-8 dB/
 
2,in terms of the ratio f/D antenna I would propose proper scalar feedhorn with flange converter >>> as a universal
offset converter that uses it is not suitable for this antenna Mr. Rajendra_please check the attachment /assembly in Dubai/
 
After these adjustments, which I appointed, I would redefine the focus and adjust the antenna for maximum gain.If after
these adjustments would be a signal from Insat satellites NOT available, I would have full confidence that the problem
is not on my side .

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• Photo annex from the author :

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   SKEW Definitor : This system I normally use to define SKEW angle at fixed antenna systems AZ/EL with converters from
                                category UNI flange

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• TEXT questions nr.3 :

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Dear Mr. Roman Dávid
 
Thanks for your reply and suggestion.Can you help me to find proper scalar feed horn and LNB's for me,or suggest
any website i can buy online.

1.Dual Ku band feedhorn for prime focus dish
2.Ku band LNB LO 9750 / 10600 (Universal)
3.Single c & ku band feed horn for prime focus
 
waiting for your reply

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• Photo annex from the author :

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                                      selected from the archive site dxsatcs.com : 9.10.2008                                        
Insat 4B at 93.5°E - KU band - uncoded HDTV transmission from India : 11 669 V SUN Direct_NG & LUXE TV
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• Answer to question nr. 3 :

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Dear Mr. Rajendra,
 
My recommendation is as follows :
 
1, FEEDHORNS_classical central antenna feedhorn to the extent of the ratio f/D from 0.3 to 0:45 !

2, FLANGE UNI LNB_ the most common type in the commercial sphere is Invacom SNF-031 and MTI AP8-TW

I personally would like to try to buy these things directly in your country , because transportation from Europe
to East Asia is expensive,Mr.Rajendra .

Dual waveguides for C and KU band I NOT recommended, because these types of port waveguide can not ensure
perfect signal transmission in the outbreak concentrated wave antenna and a highly absorbed  /attenuation /
mainly KU band frequencies !
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• Photo annex from the author :

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                                              selected from the archive site dxsatcs.com : 11.4.2009                                        
                        Insat 4B at 93.5°E - KU band : Packet DD Direct+ India_10 990-11 150-11 570 MHz


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• TEXT questions nr.4 :

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Dear Mr. Roman Dávid,
 
Thanks for your suggetion and propmt reply. One of my friend from Bankok sending me Fuji LNB for testing.
Please confirm me it will work or not.
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• sent photo presentation : UNI LNB Fuji SSI-T20

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• Answer to question nr. 4 :

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Dear Mr. Rajendra ,
 
yes this is the right type of converter for the center antenna used by Rajendra .Even if it is not a converter of
professional capacity, for a typical commercial reception you will suffice !.

• Photo annex from the author :

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                                      selected from the archive site dxsatcs.com : 10.7.2009                                        
                        Insat 4B at 93.5°E - KU band : Packet DD Direct+ India_10 990-11 150-11 570 MHz


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• Final questions nr.5 :

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Hello Mr. Roman Dávid
 
Thanks for your report
 
Today i have tried a lot to receive Insat 4B in 3.7 meter PF with FUJI LNB but no result then i try to receive NSS6 but i can
receive North east asia and south east asia beam but no India beam.

regards / Rajendra N.

                                                 
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