Advice Needed modified lnb what is best ring nubers and distance

M

mosllam

Member
My Satellite Setup
240 cm local motorized dish and 2 fixd 180 cm local dish with multi lnb VU+ DUO 2 yuner in use
My Location
Egypt- Cairo
just red a post about adjusting the scaler ring in the feedhorn

ofcorse we donot have any kind of feedhorn on sail - all we have is a cheepe chinees old tec lnb with scaler ring all in one piece
so we try to improve the recepition by modifaing a good lnb like the inverto black ultra with a very good rersult
but we do not know much about bandwidth or how mush should the ring be away from the lnb
how many scaler ring 3 rings or 4
i have tried both and olso tried long lnb and shorter one
but should it be a scintific method to do that rather than do it by trail and erorr

here is a pictures of one of my lnb ( inverto ) there is some other modified ones but a cheep chines one

the dish hasa very poor surfacc - its a local 220 cm prime foucus made in 2003 by an egyptian company

Code: 
http://i35.photobucket.com/albums/d188/mosllam/W137167901_zpscead85c7.jpg


http://i35.photobucket.com/albums/d188/mosllam/19022014604_zpsfb6f9017.jpg


http://i35.photobucket.com/albums/d188/mosllam/19022014595_zps603b0666.jpg

http://i35.photobucket.com/albums/d188/mosllam/18022014587_zps27212b9d.jpg

this is the dish - ofcorse the extra paneles doest do any good in ku band but in c band does have some 4% to 5% increse in SNR

Code: 
http://i35.photobucket.com/albums/d188/mosllam/D-1-_zps7549c08c.jpg

Admin edit. Please upload images, don't link to them
 
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The showen feedhorn is a horn for a offset dish , you need a horn with flat rings (scalaring)
 
Trust1 said:
The showen feedhorn is a horn for a offset dish , you need a horn with flat rings (scalaring)
Click to expand...

yes the second one is was just try and see the result it was better but not as good as a coplete flat feed
- but the first one is a flat but pic doesnot show it sorry about that

here is pics for first inverto a single ona and a twin made it 2 yers ago - before that we only had the chinese made cheap one like the blue one its less than two dollers in egypt but it doesnot even worth 2 dollers
the one lnb on the dish right now has only 3 rings

Code: 
http://i35.photobucket.com/albums/d188/mosllam/W137168001_zpseaa9f448.jpg

http://i35.photobucket.com/albums/d188/mosllam/Black-Ultra-1-_zpsdc97450a.jpg

http://i35.photobucket.com/albums/d188/mosllam/Black-Ultra-2-_zpsc06f26fe.jpg
 
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DishDick said:
Someone likes to tinker!
Click to expand...
donot understand what do mean exactly
i am asking for help - its tinkering when you donot know the right way
at the end its the same idea as a c120 with the feed but we donot have that - cant offord to buy from europian sites ( the lnb + feed ) is more expensive than my 220 cm dish
so better buy an old 320 cm dish if i could rather than import an invacom c 120 with its feed

but i am asking about the scintific rules which determen how long the lnb should be and its feed shape and the scaler ring number how long between the probe and the face of the rings
what the effect of dish dimentions ( Depth - f/d ratio - any thing else ) on the shape of lnb
i saw a post about that topic in this section - i beleve this is not defrent

i am not sure its tinkering because the results is much better after h fix the feed into the infrto throut - at least 10% higher signal - got weak transponder i could not recive before

the question is there a way to make it better - by teaching me the basic i can go from there
 
Mosllam, please don´t be offended - "Tinkering is therefore the process of adapting, meddling or adjusting something in the course of making repairs or improvements, a process also known as bricolage."
 
mosllam said:
donot understand what do mean exactly
i am asking for help - its tinkering when you donot know the right way
at the end its the same idea as a c120 with the feed but we donot have that - cant offord to buy from europian sites ( the lnb + feed ) is more expensive than my 220 cm dish
so better buy an old 320 cm dish if i could rather than import an invacom c 120 with its feed

but i am asking about the scintific rules which determen how long the lnb should be and its feed shape and the scaler ring number how long between the probe and the face of the rings
what the effect of dish dimentions ( Depth - f/d ratio - any thing else ) on the shape of lnb
i saw a post about that topic in this section - i beleve this is not defrent

i am not sure its tinkering because the results is much better after h fix the feed into the infrto throut - at least 10% higher signal - got weak transponder i could not recive before

the question is there a way to make it better - by teaching me the basic i can go from there
Click to expand...
Tinkering on here is a good thing ..and not an insult mate..
Most of us are Tinkerers in our own way ...constantly trying modifying and trying to improve on bought equipment.
As DD says ..please don't be offended ..it's actually a good thing that you don't just settle for what a commercial piece of sat gear claims it can do.
There are many Technically minded folk on here ..and those who just love to experiment...this is what we refer to as 'tinkering'.
;)
 
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