Got a bit of fine tuning to do. Am I correct in saying that the lnb has to point at the deepest part of an offset dish?
Aiming lnb on offset dish
- Thread starter scarecrovv
- Start date
- Latest activity Latest activity:
- Replies 17
- Views 4K
- Status
It is also very important from where you point your LNB! If LNB is located in antenna's focus than it should be pointed such a way that it's direction divides angle "lowest antenna's point" -"Focus"- "Upper antenna's point" exactly on half. What antenna are you speaking about?
It's an older type starchoice dish. (not the oval type). The arms and lnb holder are still in place but the lnb i have is loose in the holder so i'm not exactly sure but i figure it should point at deepest part of dish?
You mean, it is prime-focus? Than, of course, LNB should be pointed to the very middle of the dish whish is also deepest point of it. You could show some pictures of your dish and it's feedarms and LNB holder.
No, Star Choice (now Shaw Direct) is a service provider here in Canada. Their original dishes were standard offset dishes "round" (really oval). Once they started broadcasting on two satellites they became elliptical dishes (which scarecrovv means by saying oval).
like this one but the original lnb packed it in and my other one doesn't fit the holder properly.
elliptical is a big word for me lol
That is usual offset dish. Where is the problem then? Measure the dish and use program like "Parabola Calculator 2.0" to calculate position of focal point. When you know position of focal point, make feedarms and LNB holder in such a way that LNB's phace center is located in antenna's focal point.
The original lnb is shot.....I have a different lnb......The original lnb holder and original lnb are an odd size....my other lnb does not fit the original lnb holder properly. I am going to order another lnb like the original and then it will fit the original holder.
I have the same dish. I used a lnb holder that came with a multi lnb kit. Easy to find this type on ebay
Not the same dish. Scarecrow has the one metre. Looks like yours is the 30 inch model. Feed arm is completely different. Notice the side support struts in his photo.
However, the original clamp and lnb from the 24 and 30 inch starchoice dishes will fit the one metre. Just have to drill two small holes for the support arms.
Catamount
I'm curious as to how the "lnbf doesn't fit the holder'? What make model lnbf is being replaced? What make model is replacing it? Pictures??
If the neck of the new is small, clamp too large, should be able to cut some plastic pipe to shim it.
DISHES
'Normal' offset - a little bit taller than it's width. Winegard 2076, Channel master 1.0 meter.
Elliptical' offset - wider than it's height. 83e Channel Master
Prime Focus - width and height are equal. BUD's.
If the neck of the new is small, clamp too large, should be able to cut some plastic pipe to shim it.
DISHES
'Normal' offset - a little bit taller than it's width. Winegard 2076, Channel master 1.0 meter.
Elliptical' offset - wider than it's height. 83e Channel Master
Prime Focus - width and height are equal. BUD's.
One clamp size was for the "pop can" LNBF. I think the clamp size was 50mm. Another clamp size was for the 23mm mounts. They also manufactured a shim kit for the 50mm to clamp 40 and 23mm LNBFs, or you could use a split PVC pipe for clamping the smaller 40mm LNBF.
Thanks - I missed the side arms in the pic. The solution is still be the same. I have a 1m starchoice and it can fit that also.
Exactly! It has the 50mm with an adapter for 23mm but my lnb is 40mm. I will try the pvc pipe. That sounds like a good fix.
Somewhere here a long time ago I posted a drawing from winegard with the exact measurements for positioning the LNBF.
For the 1m dish.
From the very top of the dish to the focal point (slightly inside the scalar cover) measures 40.17.
From the very bottom of the dish to the focal point (slightly inside the scalar cover) measures 23.07
From the centre of the pan (draw an X through the four mounting bolts to find the centre) to the focal point (slightly inside the scalar cover) measures 26.22
From the very top of the dish to the focal point (slightly inside the scalar cover) measures 40.17.
From the very bottom of the dish to the focal point (slightly inside the scalar cover) measures 23.07
From the centre of the pan (draw an X through the four mounting bolts to find the centre) to the focal point (slightly inside the scalar cover) measures 26.22
- Status
