my new 12 feet ku band dish

[Golden]

friend golden last year i made a 12 feet dish with same .50 fd ratio of your dish
but that dish not catch a single tp
this is reason i ask you about feedhorn performance
now i hav dish with .67 fd ratio and give me good performance

"amrinder" Dear There Must Be Some Confusion In Your Statement Or U Absolutely Don't Know About F/D Ratio Of A Prime Focus Antenna !
U Must Be Saying That U Made A Dish Having Normal Depth (d) And Got Bad Results ' But Now U Have A Dish Having Minimum Depth (d) So U R Getting Better Performance With Your LNB Having Longer Distance From Surface Of Your Antenna !

[Rizwan Awan]

Longer Distance and less depth mean more noise, I think so

[Golden]

Longer Distance and less depth mean more noise, I think so

Then Why We Use A Flat Dish For Better KU-Band Reception !

[Rizwan Awan]

Not so flat as he claim

[amrinder]

sir i respect both you
you are senior members
but i have a bit knowladge about dish anteana
our cband lnb has fd ratio .38 to.43
which dish made in this fd ratio we called cband dish anteana and these dish working well in cband signal
normal kuband like sharp,inverto these lnb we also called offset lnb
this lnb come with fd ratio .62 to .69
all offset dish have fd ratio .60 to .70
prodolin offset dish have also .65 fd ratio
we cant make dish in offset angel of iron
but we can make easily primefocus dish in this fd
so i made dish in .67 fd
fd = focallength/diameter
if we use inverto black flenge lnb this lnb fd ratio is .38 to .43
and we catch better ku band signal on cband dish also

[amrinder]

golden sir in your dish, lnb distance from center is 6 feet and depth is 18 inch
so your lnb take signal from only 9 feet area
because if we made 9 feet dish .67 fd that dish also lnb distance 6 feet

[Golden]

sir i respect both you
you are senior members
but i have a bit knowladge about dish anteana
our cband lnb has fd ratio .38 to.43
which dish made in this fd ratio we called cband dish anteana and these dish working well in cband signal
normal kuband like sharp,inverto these lnb we also called offset lnb
this lnb come with fd ratio .62 to .69
all offset dish have fd ratio .60 to .70
prodolin offset dish have also .65 fd ratio
we cant make dish in offset angel of iron
but we can make easily primefocus dish in this fd
so i made dish in .67 fd
fd = focallength/diameter
if we use inverto black flenge lnb this lnb fd ratio is .38 to .43
and we catch better ku band signal on cband dish also

golden sir in your dish, lnb distance from center is 6 feet and depth is 18 inch
so your lnb take signal from only 9 feet area
because if we made 9 feet dish .67 fd that dish also lnb distance 6 feet

If U'll Read The Mentioned Threads Then U Can See That We @ Least Know The Difference Between OffSet And A Prime Focus LNB Curriculum . Keep In Your Mind That I Am Not Using An Offset LNB On My Prime Focus Antenna For Getting Only 9 Feet Result Out Of 12 Feet ' If I Was Doing So Then U Can Assume That I M Getting Limited Surface . Thats Why U Dont Get Any TP From Your Previous Antenna Because U Put Your Offset LNB On Your Prime Focus Antenna . I M Pretty Sure That If U 'll Try A Modified Offset LNB Or A Flange To Your Old Antenna Then U 'll get The Positive Results . I M Really Surprised To Know That U 've Made Another Antenna Having .67 F/D Just To Fit Your LNB So U Could Be Able To Get 12 Feet Results . Here Is My Modified Prime Focus LNB (Offset) Settings To Get The Max Results From Its Complete Base 12 Feet With Required F/D Ratio .

[Rizwan Awan]

Agree with Golden brother on that point, On my Dish, I lose many transponders from Hotbird, if I remove the Scalar Ring from LNB

[-==Nawazish==-]

Lnb Pipe kitne inch hight hai Golden 12ft dish ka ?

Pehley se ab kitna signals improve howa hai ?

[Rizwan Awan]

My understanding about using Feed horn with Scalar ring is along a slightly different, While I'm sure the rings have function relative to reducing the unwanted signals coming from off the edges of the dish, I think that they also function to increase the efficiency of the outside portions of the dish for the desired signals. Signals hitting close to the middle of the dish (talking prime focus here) go into the throat of the feedhorn at a pretty direct angle, and don't have any problem, but signals coming from the edges of the dish, particularly of a low F/D dish, come in at a rather extreme angle, so that the cross section of the throat opening gets pretty small. For low F/D dishes, the outside of the dish isn't very efficient.
My thinking is that the scalar rings both help to guide that signal into the throat and they actually increase the gain of signals