Suffering fools, so you don't have to.
- My Satellite Setup
- A little less analogue, and a lot more crap.
- My Location
This feedarm belongs to dual-reflector antenna, so true focal point of the main mirror located approximately where I draw red circle . The green circle represents location of the second focal point.The LNB feed looks way above the true focal point
Understood, though the measurement on the image (160+mm) is still more than I remember to the top of where the Gregorian feed is supposed to be. From memory ( and the last time I worked with a Fibo was some ten years ago) the green dot - on a 90cm reflector - was under 100mm from the top of the boom arm.
This "Aha" is not always the case , it is just for some Fibo 90s, and approximately. For me that more seems ~95mm. When we speak about Fibo 120 than distance is about 112mm. All Fibo feedhorns are same, but plastic pice which goes between the feedhorn and the feedarm differs between antenna models. There are slight difference between shapes of subs for different antenna models. Feedarms are also happened to be in different length, even for 90cm antennas.Aha, 92mm.
Not really. LNB should be pointed below the center of the dish. In case od Deltastar 120 (Fibo120) the aiming point (Le point "G") is 863mm from the top of the mirror (distance A-G) diagram is for CM dishes, but principle is the same.the lnb must look to the middle from the dish hope, i am right..
Maybe something here..