Directv and rain

[Jimbo]

I saw one pointing up the roof line, so the lnb was pretty close to the shingles.

Yes, I guess each situation would be different ...
IF its running like that, the installer should have used better surveying abilities ...
Then again, the signal comes in much higher than the arm angle.

I have seen some strange looking installs over the years.

 

[Inclined Orbit]

If you connect a spectrum analyzer to the coax coming off an LNB then point the antenna from the sky to the ground you will see a noticeable increase in noise when pointing at the ground. A similar thing happens when the dish is looking down a wall or roof at a slight angle below the satellites, the side lobes of the antenna will see the "hot" roof or wall and the noise floor will increase and the signal to noise ratio will be degraded. This will eat up some of your headroom for rain fade, mis-pointed antenna, etc.

If someone is experiencing excessive rain fade I would first peak the antenna just in case it was not installed right or it moved over time. I would also see if its got any wall or roof line within 20 or 30 degrees of the line to the satellites. If its on the back side of a roof with the LNB arm running parallel with the roof line then move the dish and let it breathe.

In fact, here is a picture of DTV engineering testing this exact phenomenon, taking data on a clean shot to the satellite and with "hot" items in the sidelobes using a prototype AT9 dish.

Yes, I guess each situation would be different ...
IF its running like that, the installer should have used better surveying abilities ...
Then again, the signal comes in much higher than the arm angle.

I have seen some strange looking installs over the years.

 

[Claude Greiner]

It isn't the rain falling on your dish that does it, it is all the water in the clouds between your dish and the satellite. You can have "rain fade" when the sun is shining on your dish, if there are huge dark clouds passing just south of you, and you might get your picture back when the rain starts falling if the worst of the clouds have passed to the east by the time the drops start hitting.

This is why putting RainX or whatever on your dish doesn't do squat for rain fade, because it has nothing to do with what is going on within a few hundred feet of your house, but rather what is going on at 50,000 feet a few miles to your south.

Exactly!

That’s why those dish cover places pretty much all went out of business.

The only thing that is necessary is a dish heater for snow, but I rarely see them necessary.