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<blockquote data-quote="Channel Hopper" data-source="post: 5837" data-attributes="member: 175144">There are three steps to getting the feed set up on a prime focus dish.1) Confirm centre point of the feed is in the middle of the reflector by running around the edge of the dish with a tape measure, and check the lengths to the center of the feedhorn.If the feed rods are adjustable with nuts on one or both ends, these can be slackened off and the rods moved in or out of the dish surface to help with the centering.2) Check the boresight if you can by looking through the hole at the back of the reflector an see if the feed entrance is square on. If this is not possible then you can tie a small wooden stake to the feed and see if it points towards the center of the dish (if you have a laser pen then take off the LNB and illuminate the dish surface through the feed - but that would be too easy )!3) Check the focal distance from the data given with the dish&nbsp; and adjust accordingly. If the installer did not leave the manual with you then the following formula is correctf&nbsp;&nbsp; =&nbsp;&nbsp; D&nbsp; x&nbsp; D&nbsp; &nbsp; /&nbsp;&nbsp; 16 dD is the diameter of the dish parabola (NOT to the rim edge)d is the depth of the dish (back of dish to front rim)Of course there are other considerations such as the accuracy of the dish itself and whether the feed really is matched to the dish for correct illumination, if it doesnt look right then the chaces are the installer has cobbled together something to get it out of his shed.If you can take some digital photos and post them then Id be pleased to let you know what youve got (a racehorse or a donkey) A 1.2m should give fine results of at least some analogue channels on&nbsp; all the satellites youve mentionedGood luck</blockquote>

[QUOTE="Channel Hopper, post: 5837, member: 175144"] There are three steps to getting the feed set up on a prime focus dish. 1) Confirm centre point of the feed is in the middle of the reflector by running around the edge of the dish with a tape measure, and check the lengths to the center of the feedhorn. If the feed rods are adjustable with nuts on one or both ends, these can be slackened off and the rods moved in or out of the dish surface to help with the centering. 2) Check the boresight if you can by looking through the hole at the back of the reflector an see if the feed entrance is square on. If this is not possible then you can tie a small wooden stake to the feed and see if it points towards the center of the dish (if you have a laser pen then take off the LNB and illuminate the dish surface through the feed - but that would be too easy )! 3) Check the focal distance from the data given with the dish and adjust accordingly. If the installer did not leave the manual with you then the following formula is correct f = D x D / 16 d D is the diameter of the dish parabola (NOT to the rim edge) d is the depth of the dish (back of dish to front rim) Of course there are other considerations such as the accuracy of the dish itself and whether the feed really is matched to the dish for correct illumination, if it doesnt look right then the chaces are the installer has cobbled together something to get it out of his shed. If you can take some digital photos and post them then Id be pleased to let you know what youve got (a racehorse or a donkey) A 1.2m should give fine results of at least some analogue channels on all the satellites youve mentioned Good luck [/QUOTE]

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