Quote:
|
Originally Posted by wejones
|
Very interesting article. I am doing something similar to reduce the
installation procedure to a methodolgy and pre-deterministic values as oppose to trial and error. I will be mounting the dish about 22 Feet high on the side of the house to get a clear shot of the southern sky -- trial and error should be avoided at all cost that high up on a ladder!
Quote:
|
Originally Posted by wejones
My dish came with a different mount, ie I got the pole mount version. My mount, however apparently came from an FC80, and was off a bit but was pretty close to being at the proper angle. My guess is that the U-bolt version is a generic mount, and is even further off. .................. WHen I measured the offset angle using the lnbf arm, I think I got 23.5 degrees, but when I estimated it using the mirrors, the angle was closer to the 24.6 specification for the dish. At least with the FC90P, it is close to being accurate, ie within a degree.
|
From your methodolgy and findings, it seems possible to recalibrate the FC90U readout scale or any dish for that matter. If we can establish parallelism between the pole and the LNBF arm as 0 degrees, the readout scale should should give you the offset angle at this condition.
Quote:
|
Originally Posted by wejones
However, the setting of this dish elevation scale only needs to be approximate, because in all liklihood you'll end up changing it when you peak on a satellite anyway. When I set up my system, I set the angle on my motor mount, before I ever set it up, and have never touched it again.
|
It is a good and easy practice to set the motor angle. I have used the set-square to set this angle, and the feeling of confidence is great!
Quote:
|
Originally Posted by wejones
I also set up the dish elevation to match what I measured in my experiments here, however I quickly started changing this setting during alignment. However once I was aligned, I looked at where it had ended up, and it was within a degree of where it was supposed to be. So the FC90P seems to come with a mount that is relatively accurate, while apparently that isn't true for the FC90U version.
|
This statement is what makes me think it is possible to calibrate out the erroneous scale on the dish mount. If parallelism between the pole and the LNBF yields the offset angle specified by the manufacturer, you can then take the difference between the readout on the scale and that of the offset angle specification as the new readout calibration factor.