So we decided to upgrade to the HD version of DirecTV, which involves (of course!) replacing, or at least supplementing our current satellite dish. It has a triple horn on it, and looks at three birds simultaneously, instead of just the one, as the standard dish does. This means that not only are azimuth and elevation important, but there's a third axis adjustment, that they call "tilt," to make sure that you're seeing all three of them.

I put up a new mast, got it plumb, set the settings on the tilt and elevation to what they're supposed to be for southeast Florida (45 degrees for both), hooked up the cable, pointed it in the general azimuthal direction (about thirty degrees south of west), and got nada, bupkis, no signal.

Is the cable good? Yup, and here's the weird thing. When I drop the elevation to thirty degrees or so (fifteen below where it's supposed to be), I get a reasonably strong signal on the upper transponders of Satellite A, starting with number 22. No signal on transponders 1 and up (which are the ones you're supposed to use to align the dish). Also no signal on either of the other two birds.

So something's happening, but not what should be happening. What are the chances that this is an LNB problem? The first dish I ever installed, years ago, had a bad LNB right out of the box (which drove me crazy trying to figure out what was wrong--fortunately, part of the deal was a free upgrade to a dual LNB, and when I put in the new unit, I got the signal right away).

Is there anyone out there familiar with the situation who could diagnose this, so I can just take the LNB back to Circuit City and exchange it? Or are these symptoms of something else that I'm doing wrong (though I'm wracking my brains at this point trying to figure out what else it could be).

I used to work in a Dish installer warehouse (god have mercy on my soul). What you have there is called a Superdish. There are 2 kinds of LNB for them. When ordering them from Dish, the item code is almost exactly the same for both. You might have the wrong one.

By the way: What in god's name would posses you to buy anything from those geniouses at Circuit City? They are salesmen, not technicians. lol

Oh. DirecTV. Damn. I need to lay off the sauce. My apologies.

I remember DirecTV had a channel for a few days, showing all the steps required to install it properly. It was a bit more complicated than a normal install and they kept showing off a calibration device used to check the various frequencies in use. This device was more complicated than the one I have for my non-HD signal.
Sorry that I can't remember more about it, but it was a few months ago and I don't have HD.
You may need to call a private installer on this problem.

I have a Dish 500, a two sat dish. I had some roofing work done, and the roofers took the dish down. When I put it back up, I couldn't get the right signal. I fooled with it for hours and hours and finally convinced myself that the roofers had damaged the LNA/switch that resides in the head end, so I ordered a new LNA.

Short version: anybody want to buy a used Dish 500 LNA?

Be very sure that you are seeing what you think you're seeing. It's extremely easy to have the "left" sat on the "right" antenna, and then the "right" antenna is pointing at deep space.

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Why oh why are you doing this yourself? I have an HD triple sat dish from Directv and they installed it for me! you just call Directv and they send someone out. ALso, I assume that you have the right receiver for it? That usually has a tutorial. At least, the Tivo HD 250 version does.