Full size 5 LNB vs Slimline re rain fade

[PCHDTV]

I had a full-size 5 LNB installed back when they were new. Ever since my system has been much more prone to rain fade. I came from a 3 LNB set-up.

Two questions:
1. Is the slimline 5 LNB less prone to rain fade?
2. Can my current mount be used for the Slimline if I choose to replace the full-size unit? I DO NOT want more holes put in my roof, nor do I want the current mount removed.

Note: I have excellent signal strength across the board when skies are clear.

Thanks in advance!

[jdspencer]

By full size 5LNB do you mean the AT9 sidecar dish? It was somewhat rectangular. And the 3LNB was probably the old Phase III dish.

The Slimline 3LNB (AU9 - SL3 or SL5) uses the same mount, I think, as the AT9 (2" OD post). Does your current mount have the monopoles installed? Was the mount changed when you went from the Phase III to the AU9?

If you don't need the 110 and 119 satellites the the AU9-SL3 will be sufficient.

Please post your signal strengths. What you think is excellent may still be able to be improved.

[PCHDTV]

By full size 5LNB do you mean the AT9 sidecar dish? It was somewhat rectangular. And the 3LNB was probably the old Phase III dish.

The Slimline 3LNB (AU9 - SL3 or SL5) uses the same mount, I think, as the AT9 (2" OD post). Does your current mount have the monopoles installed? Was the mount changed when you went from the Phase III to the AU9?

If you don't need the 110 and 119 satellites the the AU9-SL3 will be sufficient.

Please post your signal strengths. What you think is excellent may still be able to be improved.

Yes, I have the AT-9 and it is installed with monopoles. The mount was new with the AT-9 as the previous dish was mounted on the fascia, not the roof.

Here are my signal strengths:

101
1-8 97 97 96 0 96 100 96 100
9-16 96 100 97 80 99 100 96 100
17-24 98 0 97 100 97 100 97 100
25-32 98 0 96 100 98 100 97 100

110
1-8 NA NA NA NA NA NA NA 79
9-16 NA 78 NA 82

119
17-24 NA NA NA NA NA 93 85 88
25-32 63 95 97 93 81 96 0 96

99c
1-8 91 93 86 91 87 90 89 89
9-16 89 91 90 92 95 95

99s
1-8 0 17 0 0 0 0 NA NA
9-16 NA NA NA NA NA NA 23 0
17-24 50 63 0 0 87 91 18 0

103s
1-8 0 0 95 0 99 0 NA NA
9-16 NA NA NA NA NA NA 95 96
17-24 74 77 0 97 80 85 96 88

103c
1-8 94 94 92 92 91 91 91 93
9-16 91 92 92 95 92 95 NA NA

99(s) is a spotbeam so I should not be concerned about the poor signal, correct? I'm in Florida, FYI.

Thanks!

[jdspencer]

Those strengths look pretty good to me. What channels are suffering from rain fade? The 99s and 103s sats are the spot beam satellites. I don't see a need to get a Slimline dish.

[boba]

Directv should upgrade you to an AU9 free of charge if you are having problems with the AT9. The AT9 components can only be replaced with the same manufacturers parts. The AU9 is interchangeable parts so Directv is replacing old AT9s as they fail and the connecting cables on the sidecar were prone to problems.

Both 99 & 103 are Ka and more prone to rain fade. My mother in Sarasota told me today they have been having some strong late afternoon storms. This is pretty normal with the oceans around FL.

[ndole]

Probably needs some dithering. Also, do you have any possible tree cover?

[texasbrit]

Probably needs some dithering. Also, do you have any possible tree cover?

No, it does not really need dithering. The 99c and 103c signals are all in the 90s or at least very high 80s and it isn't really worth trying to improve on those. Even if you get into the mid-90s for all the 99c/103c signals it will have no real effect on rain fade.
Rain fade on the Ka signals is almost inevitable. They are much more susceptible to rain fade than the Ku SD signals because the raindrops are of the same order of magnitude in size as the wavelength of the signals. It's nothing to do with the dish.

[PCHDTV]

Those strengths look pretty good to me. What channels are suffering from rain fade? The 99s and 103s sats are the spot beam satellites. I don't see a need to get a Slimline dish.

Thanks for all the input guys. I never check a full gamut of channels when I get the rain fade, but I typically only watch national and local HDS...they all go when the rain comes. Trees are not a problem.

It's not a big problem, it's just that it happens more easily and often with the AT-9.

[cartrivision]

Thanks for all the input guys. I never check a full gamut of channels when I get the rain fade, but I typically only watch national and local HDS...they all go when the rain comes. Trees are not a problem.

It's not a big problem, it's just that it happens more easily and often with the AT-9.

That explains why you are seeing more rain fade. Almost all of the HD channels come from the new KA band satellites at 99 and 103. Previously you probably got most of what you watched from KU band satellites, and KU band is less susceptible to rain fade than KA band.

[bobnielsen]

Unless there is a problem with your AT-9 (and the numbers don't indicate that) you would probably not see any appreciable difference if you switched to a Slimline.

[PCHDTV]

That explains why you are seeing more rain fade. Almost all of the HD channels come from the new KA band satellites at 99 and 103. Previously you probably got most of what you watched from KU band satellites, and KU band is less susceptible to rain fade than KA band.

Thanks. This may be a dumb question, but I don't keep up with the tech end of D* as much as I should. Were the HD channels previously on the KU band before they went MP4? Just curious since I was HD before the AT-9.

[sptrout]

I have had problems with low recieve levels (vs. the other sat's.) on my HD dish since day one (3 years - old five LNB, gaint antenna). Last week a DTV contractor came to may house to test my failing HR20 so I could get it replaced with a new HR22 (actually new, built in July).

I had also asked to have my dish checked due to rain fade problems (I have complained to DTV before and the service folks always said everything was OK). This time the tech was an ace IMO. He didn't buy into the levels being low on the two HD sat's only, so he started checking everything all the way to the dish. He then replaced the 5 seperate LNB mess with a new, all contained in one box LNB assembly - no change in Rx levels. Not giving up he decided to replace the dish with a new SlimLine (but kept the just replaced LNB assembly). That did the trick! I gained 15-20 points on all the HD sat' transponders.

He concluded that the dish was warped, but it was not visibly warped; looked fine. We both came to the conclusion that the dish had to have been warped from day one, probably when the installer threw in into the back of his truck to come to my house over three years ago. This is one time that I am glad I am buying DTV's Protection Plan, no telling what last week would have cost.

[bobnielsen]

Thanks. This may be a dumb question, but I don't keep up with the tech end of D* as much as I should. Were the HD channels previously on the KU band before they went MP4? Just curious since I was HD before the AT-9.

The MPEG2 HD channels (a few of which are still in existence, for a while anyway) were on Ku band on the 101, 110 and 119 satellites.

[jdspencer]

Thanks. This may be a dumb question, but I don't keep up with the tech end of D* as much as I should. Were the HD channels previously on the KU band before they went MP4? Just curious since I was HD before the AT-9.Yes! The Ku sats had MPEG2 HD. The Phase III was sufficient then for HD.

[PCHDTV]

OK, cool. It sounds like what I've been experiencing is the new "normal" rain fade when it comes to HD on the KA band.

[ndole]

No, it does not really need dithering. The 99c and 103c signals are all in the 90s or at least very high 80s and it isn't really worth trying to improve on those. Even if you get into the mid-90s for all the 99c/103c signals it will have no real effect on rain fade.
Rain fade on the Ka signals is almost inevitable. They are much more susceptible to rain fade than the Ku SD signals because the raindrops are of the same order of magnitude in size as the wavelength of the signals. It's nothing to do with the dish.

That's a very cool factoid