Convirting a C-Band Dish

[bugeyes]

Would I be correct in assuming that when installing a DPP LNB in an old C-Band dish, the location of the LNB is right in the center in the bracket for the old analog element?

[Crazy1_79]

i have seen a old friend of mine do this. and if i remember correct. I think it may have been offset just a bit.

[bugeyes]

How do I calculate the offset? Also,did the increased size of dish generate any more signal stregnth?

[Crazy1_79]

i believe he had full signal and i think he just had it offset a bit an then moved lnb a round until he had singal. perhaps the offset was unnecesary he still had other lnb's on it. it was a few years ago and man has passed awayh since so i can't ask him.

[ah33919]

From what I understand, the signal my be greater once you find the correct focal point but the focal point on the dish itself is more precise and may be a bit harder to obtain when you have a larger dish.

[bugeyes]

Wouldn't the focal point be the center of the parabola (or the center of the sphere that the dish is a section of ? If so, i think that is where the center of the bracket of the old c-band element is.

[Crazy1_79]

you are correct bugeyes. but since the dish is so large and with modern ku band lnb's i believe the error for margin much greater than the days of BUD

[bugeyes]

1---So, if I'm reading you right, I should be OK just mounting my Dsh DPP right into the same place where the old unit was. Correct?
2---Is there any advantage with this application in mounting it off-center and, if so, where can I find a play by play on how to calc that?
I am a thousand miles south of the Mexican border but Damn! Is this worth it? I've got a sig stregnth of 75% now but can only see 119. I'm hoping to pickup 110 as well. Thx for your help. B

[odnok]

I have 8ft. fibre glass dish,at first setting was offset almost a foot from center focal point with good signal on 119.I then moved dish till I had good signal with LNB mounted in center of trypod type feedhorn mount,and all wanted sat. come in good by moving with original c band equipment.I got weaker signal with motorized 33 inch dish setup.
A WORD of Caustion.Do Not use cheapo sat. finder directly in front of big dish.you'll fry it.

[Crazy1_79]

I have 8ft. fibre glass dish,at first setting was offset almost a foot from center focal point with good signal on 119.I then moved dish till I had good signal with LNB mounted in center of trypod type feedhorn mount,and all wanted sat. come in good by moving with original c band equipment.I got weaker signal with motorized 33 inch dish setup.
A WORD of Caustion.Do Not use cheapo sat. finder directly in front of big dish.you'll fry it.
that's a man talking from experience right there. LOL

[bugeyes]

I'm not sure if the motor is functional. Can (or sould) I be able to see 119 and 110 without moving the dish? I suppose I could use my lat & long to figure inclination and such.

[odnok]

YES. 2LNB's,even with dual lnb oval dish setup.