Centering feedhorn on a BUD

[brians]

Is there an easy way to center the feedhorn on my BUD?? My C-band is good, but since getting my DVB receiver I'm watching alot more KU and it's not so good. Can get most transponders, but signal quality is usually below 50. And I've bumped the skew and dish position on my 4DTV receiver and gone out to adjust elevation up and down abit. I just eyeballed the feedhorn when I put my dual C/KU on a few years ago and figure I may need to do a more accurate job on the feedhorn centering. I know I can buy a laser but kind of expensive for a one time use!! Any great minds out there??

[starman]

Just use a measuring tape, measure from the edge of the feedhorn to the edge of the dish, top,bottom, and to each side.

[bobkat]

Just use a measuring tape, measure from the edge of the feedhorn to the edge of the dish, top,bottom, and to each side.

Yes, that's the best way. Remember also that not all BUDs are truly KU compatible, especially the mesh type. Since the wavelengths of KU band signals are much shorter than C Band wavelengths some or all of the KU signal may go right through the mesh rather than be relected by it back to the feedhorn. The solid spun aluminum BUDs did not have this issue. Solution if you have a mesh type BUD ---> cover the whole thing with lots and lots of tin foil :lol: :lol:

kat

[phantomtri]

should there be a measurement from the center to the lnb as well as from the sides
i mean i have a c band lnb on the dish as well so i want to put a c/ku lnb on it also in front of it a small lnb that comes with a fortec system to bump up the signal with brackets
so should there be a specofis distance from the centre to the lnb or just put it on the plastic head thats there
or measure from all sides to get straight on in the dish infront of the cone but will that work if the lnb is a small one or does it matter

[stal4]

Phantomtri,
Do you mean you have a seperate ku-band lnb, that is right next to the main feedhorn that supports the c-band? If this is how I think you have you dish set up then I do think you may have an issue with receiving a strong signal. I pretty sure you dig dish is a prime focal type, so that would probably be a problem. As far as making sure that the feedhorn is directly centered to the center of the dish, I used a small pen laser with a straw inserted over it to keep it on and then tie wrapped to a 45° carpenters tool so I could see exactly where my feedhorn needed to be adjusted to make sure that it was centrally positioned to the focal point of the dish. As far as the focal length. I bought one of these 3/8 inch metal rods from home depot and cut to length that I needed for my required dish focal distance minus about 3". For those 3" I put another staw that I can adjust to get fine measurements for my focal distance when I do measure. Most of this aligning is done early in the morning before the sun comes up, so that I can the the laser light.
art