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Originally Posted by brentb636
You should also know that several of us, with your same dish and LNBF combination have had to add 5 or 6 degrees to the dish elevation to maximize our quality signal. I don't know the reason , but there are several possibilities.
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I'm not sure of the reason either, however about a month ago I posted a message which had the offset angles of various offset dishes, and these varied from somewhere around 20 deg to up near 30 deg if I remember right. even dishes from the same manufacturer varied by a few degrees. The reason I think this is important is that if you look at the dishes available at say
Sadoun, you see that there are a couple different mounts that seem to be used with any of the dishes. Since it is the mount that has the elevation angles, to be accurate, the mount has to be matched to the offset angle of the dish, and to how the dish connects to the mount. My GUESS, and I hope Sadoun will comment, is that these mounts are not specific to the particular dish, but are generic. If the mounts sold by Sadoun are specific to one of the Fortec dishes sold by Sadoun, then it might only explain being off by a couple degrees, not 5 or 6, but if those mounts are not Fortec mounts at all, but generic, then that could explain why the readings are off so far.
HOWEVER, this is really not all that important with respect to alignment, assuming that you set the motor angle and search for your southern sat by varying this dish elevation, because the motor angle scales are definately specific to the motor, so you can trust them to be fairly accurate, and assuming that the motor angle is set properly, then the dish elevation will be set perfectly without ever looking at the scale by locating your southern sat. Of course being off by 5 degrees may make it harder to locate the southern sat, but once you find it, you'll be set right. Right enough to set and never touch again if you are careful.
Of course, there is another possible cause for angles to be off by 5 or 6 degrees, and that is that a common mistake is the confusion between elevation numbers and the "latitude" scale on motor angles. Over the years I have communicated with several people who have confused these two, and it is particularly confusing when your latitude is in the 40-45 deg range, where the numbers are similar whether you are dealing with the right number or the 90-X version. I've seen many people set their motor on like a 43 degree elevation instead of 90-43=47, because their latitude was 43, and this mistake will make your dish elevation off by 4 degrees right there. And the thing is, that even making this mistake, you will still be able to track many of the sats on one side of your arc, but not all and probably won't be able to hit things on the other side of the arc, so some people make this mistake and don't even know it.