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Message: <blockquote data-quote="2old4this" data-source="post: 9934" data-attributes="member: 174998">But it surely isn't just scanning "blindly", effectively moving one pulse at a time and then seeing if it has a signal matching any of the hundreds of transponders it has in its memory (allocated to all the different satellites)...?It must be moving the dish to a particular position where it expects to find a particular satellite, and then looking for a signal on a default or beacon transponder for that satellite, using that signal to peak/fine-tune the dish position. In other words it's starting off with some basic idea of where each satellite should be found. And my point is - that basic idea is either what you manually entered as the position (NOT just the longitude, but the actual position in terms of the counter), or else it's using what it picked up from the settings you loaded - which could be completely "wrong" for your own equipment.Imagine that the settings you have loaded were originally created on a system where Astra1 at 19.2east longitude was at position 2000 and Hotbird at 13east at 2500. Don't worry about these numbers. They are purely arbitrary, to illustrate a point.You load those settings into your receiver, and start scanning. Let's imagine that the receiver does manage to locate Astra. Now it moves to Hotbird. To do that, it knows it has to go from counter 2000 to 2500. IE move 500 pulses/counts. But let's imagine that your particular motor is different from that of the original system. Your motor only passes half as many pulses through for a given amount of travel. So the dish, in moving 500 pulses actually overshoots Hotbird on your system. Where it ends up is anybody's guess. It might even by coincidence land on a different satellite, with a signal on the same transponder it would expect to find on Hotbird. So it would scan the wrong satellite, and you might end up with (say) Sirius channels assigned to Hotbird. Alternatively (more likely) it will find no signal at the overshot position and you will be left wondering why it failed to locate some of the satellites...Or am I totally missing some clever trick the Strong receiver uses to avoid this problem?2old</blockquote>

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