Tuning SES 2 @ 87°W

[Magic Static]

There is a mystery I want to solve. Many of you have stumbled upon this. When tuning 87W there are wide variances in S&Q amongst the transponders. In particular, you tweak ME and THIS and loose RTV on 4080 or 3800. Or the other way around. Now this not what you would expect. I can get METV at 100%Q and not a whiff off RTV. I can get them all, but not as strong as tuning one individual transponder. I'm thinking this is brought out by some inaccuraccy in the dish assembly, ie alignment of the LNBF.
I've read many posts mentioning this problem but never saw one explaining what is happenning here. Could this be exaggerrated by dishes with low F/D ratio? Could there be a situation where say the Scalar ring is really not a constant, one size doesn't fit all? I'd like to nail this down. Do different frequencies take different paths along the same line? Things that make you go hmmmmmmmmmmm

 

[Scott Greczkowski]

Read my review of the new AI Turbo S2 meter... I had the same issue except I could not get a wiff of RTV on 3800.

Turns out after testing that my LNB was slightly off center, so by bending the LNB support arms a little now I am getting above 80 signal readings on most transponders on all satellites! Including a solid 85 on the RTV 3800 transponder (but not a peep on the 4080 transponder!)

 

[Magic Static]

Well like I said I can get them all inc 3800 & 4080. Not missing anything, just trying to understand the science behind this pheonom.
And I too am learning the AI TurboS2 nice meter! But I didn't get a discount on mine like you did

 

[KE4EST]

I would like to know too. If I go out to the dish with my meter and tweek anything I can think of including bending the arm a bit to get 3800 I lose 4080 or vice versa. So weird!

 

[turbosat]

Seems like all the different parameters of dish aiming have to be just right to get that satellite with high numbers of signal/quality. I get those RTV channels on both tps well, using a 10' Sami dish, without having to do any tweaking once I had a receiver that would pick up S2 signals. Polarity control seems to have a lot to do with it though, even if your dish is tracking well. Using old lnb with polarotor, I can bump the polarity just once and lose those S2 channels. They're really picky.

 

[signal.quest]

This might be similar to my problem trying to get the CBS S2 TP's. I think I am tracking the ARC, but having trouble w/ high FEC S2 w/ 10 footer. Is the polarity most likely the problem compared to other settings? If so, I was thinking of trying an old LNB and polarotor. I have a Chaparral and old Analog receiver to mess with.

 

[RT-Cat]

.....Polarity control seems to have a lot to do with it though, even if your dish is tracking well. Using old lnb with polarotor, I can bump the polarity just once and lose those S2 channels. They're really picky.

Same thing here with my 8 foot orbitron and polarotor. Just a few numbers and pick up or total loss. One of the big reasons I like being able to adjust the polarity.

 

[Magic Static]

I'm starting to thing it is a feed horn setup problem. When we get some nice days I'll take a laser to it and check all the angles and feed measurments. I tweaked the elevation adjustment a couple days ago and everything comes in good. I just think it could be better. I get both RTV transponders and LPB on the KU side. I'm a little weak on KU in the center of the arc. But there is really nothing I watch there except BVN on 113.0W, but I can get that real good from 101.0W.

 

[rrob311]

I have learned quite a bit about this through trial and error in the last several months. With S2 signals a larger dish is the key. I am in Sourthern NH and I have noticed on 87w that This and Me come in pretty easy with my 10 footer with This consistently being stronger along with the encrypted Caribbean gov. mux. If I peak the dish I can get both RTV transponders but I pretty much always get 10-20 q higher with the 3800 mux. I have noticed with S2 signals I am able to max the quality meter on my S9 to 85% on my Comtech dish which I have not been able to do with standard signals. My 10 foot dish is a bit twisted up but if I work on it long enough I am able to also get the weathernation muxes which seem to be a bit weaker than the RTV ones.

 

[Cham]

I've noticed that if I bring the dish up about .1-.2 degree 4080 comes in a bit better, can get 85% where it still might break up a bit. The satellite might be inclined just a bit in orbit. I often elevate the dish a bit in the fall to compensate for snow loading. Playing with the skew can get another 5% but then the others drop off. Certainly a good place to use a corotor feedhorn!

I've also noticed S2 signals below about 84%Q won't play well and often won't lock. This is for all signals, not just this satellite or band (c/Ku), at least on my receiver.

Another observation regarding the AzBox, sometimes 4080 doesn't lock properly even with a 85+Q. If I delete the TP and re-enter the parameters and re-scan, the stations come in fine. It seems the FEC or something else gets messed up.