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Guest Message by DevFuse

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Small C-Band antennas


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7 replies to this topic

#1 OFFLINE   raj2001

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Posted 25 May 2003 - 10:35 AM

Anyone have any idea what is the smallest size C-Band antenna I can get away with? I've seen in satellite books they have 3 foot dishes for use on RV's. Any truth to that?

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#2 OFFLINE   Jacob S

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Posted 25 May 2003 - 11:56 AM

I thought I had seen a while back where there was a phased array solution for this in which made it a lot smaller antenna to pick up the big dish frequencies. I cannot find the link though. I am also wondering if the toroidal dishes that have a sub reflector will work with the C-Band dish frequencies.

#3 OFFLINE   JohnH

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Posted 25 May 2003 - 12:24 PM

Originally posted by raj2001
Anyone have any idea what is the smallest size C-Band antenna I can get away with? I've seen in satellite books they have 3 foot dishes for use on RV's. Any truth to that?


Size depends a lot on whether you plan to receive digital and/or how much sparklies you can accept.

The range is usually 5'solid to 10' mesh.

#4 Guest_AntAltMike_*

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Posted 25 May 2003 - 12:24 PM

Three foot dishes won't work for C-band for most applications because the C-band satellites are just two degrees apart, but the 3 foot dishes have too wide a beamwidth and pick up too much interfering signal from the satellites in the adjacent slots.

Anything smaller than 6 feet would be very unreliable. A few years ago, I installed a four foot C-band dish that a customer had obtained to pick up some unscrambled Arabic programming, which might have been on W3 or its predecessor, or on some other satellite around that slot, and there was one transponder he could receive well because the adjacent slot transponders on the same frequency were unused, but he couldn't develop watchable pictures on the transponders on which the adjacent slot transponders were in use.

What programming do you desire to watch, and in what part of the country do you expect to be using this?

I think Anderson Manufacturing still manufacturers solid dishes smaller than 6' in diameter that can be fitted with a C-band feedhorn. The can be purchased with so-called "ring mounts" that are like hula-hoops equal in diameter to the dish and hinged to it at one point, so you can set them up expediently without having to develope a mast structure.

#5 OFFLINE   Mike

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Posted 26 May 2003 - 11:34 PM

In California, 5 ft dish for analog is watchable with sparklies. I don't mind sparklies as I've seen them for years, but others I know hate them and want the clear picture. For MPEG digital, it's rough. Quality barely gets above 60 on most birds making it unwatchable with several breakups. I've put a c-band lnb on one of my primestar dishes and it's doable for analog with lots more sparklies than the 5 footer, but 3 ft will not work on digital at least the few I've tried. I think you being in NYC would show the same results as me in California. You might have better pictures in Kansas or somewhere in the midwest.

#6 OFFLINE   Jacob S

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Posted 27 May 2003 - 07:30 PM

Aint there lnbf's that pick up better than others allowing a smaller dish?

#7 Guest_AntAltMike_*

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Posted 27 May 2003 - 08:48 PM

Originally posted by Jacob S
Aint there lnbf's that pick up better than others allowing a smaller dish?


No.

#8 OFFLINE   sampatterson

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Posted 27 May 2003 - 10:29 PM

I used a 6 foot dish for years in Oklahoma. Pretty good quality but some sparklies (in red pixels) on some channels. I have heard that digital Cband is even more finicky than analog so don't know how well a 6 footer works.




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