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To me the most mysterious part of setting up a new dish is peaking the LNB. I read a lot of posts where people say that you have to aim the LNB precisely at the center of the dish, and that it should be an exact distance from the center. But this gets complicated by several factors that to me make this seem more like guesswork than science.

The first problem is that many LNB's and scaler rings are manufactured to very sloppy tolerances. It should not be possible to put an LNB into its matching scaler ring and aim it 15 or 20 degrees off center but unfortunately that is all too possible with some modern LNB's. So even if you get the scaler ring precisely centered somehow, you still have no idea if the LNB is centered since it can flop around inside the ring.

I have wondered why someone does make a small ring that would snap around the outside of an LNB, similar to the way a pair of headphones fits around your head (so it would fit LNB's of slightly varying sizes snugly), with about 8 laser LED's around the outside that all point straight down toward the center of the dish. If there is no way to make such a thing with enough precision to give good aim, then you understand why I say that trying to aim at the center is more guesswork than science.

I see people suggest a string test, for example to make sure the scaler ring is at an equal distance from the edge of the dish on all sides, or that the outer rim of the LNB is. First of all, I would love to know where people are getting this non-stretchy string that can measure with such great precision. Even kite string or fishing line will stretch a little when you pull on it and if you pull a little harder on one side than the other, your scaler ring or LNB will be off a little. And that assumes that you can attach the string at the exact same place for each measurement. And that when you get it right and go to tighten it down, nothing moves.

Then there is the problem of the support arms being a little to short or a little too long. Usually when you buy a LNB they do not give you very long bolts or screws for attaching the scaler ring, so you MIGHT get a couple washers between the scaler ring and the supports, but that's about it. And nowadays they may be using some weird metric bolt that would be difficult to find in a longer length in an American hardware store.

So then you do the calculation to figure out how far the LNB should be from the center of the dish, and where it should be in relation to the scaler ring. Some dishes have a bump or a metal plate in the center, so do you adjust for that? And where do you measure to on the LNB? The outer rim? The back of the throat (as if I really want to take that protective cover off and jab a metal tape measure in there!)? I don't know why LNB manufacturers don't inscribe some kind of measure line on the outside of the LNB, so you know where you're supposed to be measuring from. Or at least put a diagram on the box so you know where to measure from. I see some documents, probably written when most people were using Chaparral feedhorns with bolt-on LNB's, that suggest some fraction of an inch. I seriously doubt that's the same measurement that should be used with an integrated LNB that's made in a country that uses the metric system.

So in my experience, if you carefully measure everything and you think it's all correct according to the calculated values, if you then loosen the bolts on the scaler ring and slide the LNB in and out and maybe twist it a little you can gain five or ten more points of signal quality. The setting on the side of the LNB is nowhere near what it should be according to your calculations, but that's where it winds up getting the best signal. In almost every case but one or two, I have found that sliding the LNB in a little closer to the dish improves the signal. Of course the whole time you are doing that you're fighting to keep it straight because of the aforementioned slop between the outer diameter of the LNB and the inner diameter of the scaler ring. Sometimes it seems like trying to keep a pencil centered in a doughnut hole.

And of course while doing that you are also trying to check for the best skew angle. I honestly don't know how anyone gets this right. I have never put up a dish where I have been truly happy about the final position of the LNB, even in the couple of cases where I spent several hours trying to get it right.

If C-band enthusiasts were a bigger market I'm sure someone would come out with some kind of aiming aid that would make this process easier, especially with the newer integrated LNB's. Right now it seems more like intuition and trial-and-error than science. Then again, if they did it would probably be too expensive for many of us, and it would be complicated by the different types of LNB mounts (3 arms, 4 arms, buttonhook, etc). But to me, this is the most frustrating part of aiming a dish. You'd think it would be dead simple, and it might be if everything was manufactured to precision tolerances, but unfortunately that's rarely the case.

What I suspect is that a lot of guys do everything "by the book" and don't take into account that the measured distance to the center of the dish might be a significant distance closer or further than the reflective center of the dish, especially if there's a bump or metal plate there. Or that on LNB's you're not told where on the feedhorn you should be measuring to. Or that string is stretchy, or that the outer rim of the dish might be a little warped and throw off all those careful measurements. As I say, I've picked up four or five points just by loosening the bolts on the scaler ring and moving the LNB around by hand, to a place where the calculations say is all wrong, but nevertheless my receiver is showing improved signal strength and/or quality. I don't know if you guys have any secrets for doing this correctly but if you do, and they don't cost an arm and a leg, I would love to hear them.

One other thing, I have seen it suggested a couple of times to use a cheap ruler with a laser pointer to aim the LNB at the dish center. For the life of me I cannot visualize how this would work. If someone could post a picture or video of how this is done, it would be very helpful, because at the moment I don't understand that at all, unless maybe you guys are using some kind of ruler I've never seen before.