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Discussion Starter · #1 ·
Quote:
Originally posted by andrewsi:
Assuming you're using an oval dish...
Yes, I have the oval dish and the receiver has the correct settings (Oval with three LNBs). I was curious where/how people were getting azimuth and elevation values for just the 119 satellite. This type of info should help me determine if I have a line of sight problem or if it might be hardware related.


I also think I might mount my extra (single dual LNB) dish on a sled and point it at the 119 satellite. Once again, the correct azimuth and elevation values would be needed for this.


Richard

 

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I think I tried to figure this out once and decided that you can probably extrapolate the values given the known figure for the 101 satellite (round dish numbers) and the value for a 2/3-LNB dish (which probably corresponds pretty directly to the 110), then continue the line across the sky in the same direction and the same quantity in number of degrees of az and elevation, and you'll probably find the 119...


As long as you get close, the signal strength meter is obviously going to help you lock it down and maximize the signal, if you're going to try the two-dish route.


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Andy
 

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Discussion Starter · #3 ·
Quote:
Originally posted by andrewsi:
I think I tried to figure this out once and decided that you can probably extrapolate the values given the known figure for the 101 satellite (round dish numbers) and the value for a 2/3-LNB dish (which probably corresponds pretty directly to the 110), then continue the line across the sky in the same direction and the same quantity in number of degrees of az and elevation, and you'll probably find the 119...


As long as you get close, the signal strength meter is obviously going to help you lock it down and maximize the signal, if you're going to try the two-dish route.

Andy,


I realized the same thing a few minutes ago. I also looked at some online 'look angle' calculators as well. I have some numbers from them for the 101 and 119. It seems that none that I found did calculations for 110. I am also not sure now if the values provided by my receiver are true or magnetic north. I am assuming that they are probably magnetic north as that would be the easiest thing to give Joe Sixpack. The look angle calculator was true north. The calculator on DirecTV's site (which only does 101) appears to be for magnetic north (using my 8deg West magnetic declination).


Regardless, the elevations should be right on and the azimuth numbers can be calculated as I know my magnetic declination anyhow. I can swing back and forth a few degrees to find the best signal either way.


I sure hope this turns out to be a hardware problem as I don't want to move my main dish again or setup a second dish.


Richard


[This message has been edited by Richard Casto (edited 04-23-2001).]
 

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I'm sure the azimuth numbers are magnetic. Since the installation's reference point is always a magnetic compass, they have to be taking magnetic variation into account when they give the user the numbers to use.


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Andy
 

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Something else just struck me about your original problem:


You said in the original post that when you dangled the LNB for Sat-119 in the general vicinity of the slot for Sat-101, you got a signal (but not when it was "installed" properly.)


Here's my brain flash: Of course the receiver will show you a signal on Sat B in that case: It's putting out the 22Khz on the line to select Sat B, and it's getting a signal back, and so it's assuming that what it's getting is Sat B. But what it's really getting is the signal from Sat A - and I bet you the STB can't intrinsically tell anything from the incoming signal that allows it to know the difference.


Reading back, I think this is what you meant all along - so that bad aiming, or interference from the trees or the neighbor's house really seems to be the most likely culprit, since you got a signal from the LNB... just not from the right satellite.


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Andy
 

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Discussion Starter · #6 ·
Andy,


Ok the 101 signal via the 119 LNB now makes sense. I guess I had assumed that their might have been something in the 119 bitstream that said 'I am from 119' and that the receiver knew when it was getting a lock on 119 vs 101. But I guess it only is determined by the way the multiswitch is wired and the signal the multiswitch puts out.


If this is true, how could I test 119 by itself? I seem to have seen a few suggestions from people that you run the output from the 119 LNB directly into your receiver (bypass the multiswitch). How would the receiver know to assign the signal to 119 vs. 101 or 110 (in the signal strength section)? Do you just tell the receiver that you have a round dish with one LNB and it puts the 119 signal on the 101 position?


This makes me feel even worse as it keeps pointing at a line of sight problem. I think that the 119 satellite might be below the 'horizon' of my neighbors roof. http://www.avsforum.com/ubb/frown.gif


Richard
 

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Hello fellow posters. I'd like to jump in on this one. I recently installed a Mits SD-5 and I'm also having problems getting a good signal from the 119 sat. The best I've ever got was +/- 30. The 101 comes in at about 80-90. Is it just a matter of tweaking the aim or could it be a STB issue? Thanks in advance to all replies.


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M. Maylock
 

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Well, I would be surprised if it was possible to connect a round dish pointing at 119 directly to the STB and have it work, because that's a setup that the box certainly isn't expecting from a software standpoint, although anything I say beyond this point would be conjecture.


The box is expecting to select between LNB 1 and LNB 2/3 via the 22Khz tone, but it's only going to put that out if you tell the receiver you're using an oval dish. If you tell it it's a round one, it's going to assume that it's looking at Sat A. The real unknown is what the STB would do with the actual bitstream it starts receiving at that point if it's actually a round dish pointing at Sat B rather than A.


I think the best bet is to simply wire the second dish pointing to 119 to the multiswitch where the 2nd LNB used to go, and then try to find a location where the second dish gets good reception.


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Andy
 

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Maylock:


First step would definitely be to tweak the aim, make sure the post is really level and that the tilt is set correctly, and then see if you can strike a balance between the two satellites that boosts 119 for you, even potentially at a little expense to 101 signal strength. I don't know how low on the horizon 119 is for you, so of course you probably want to try to visualize where it is and make sure you're really clear of obstructions.


In Seattle, the 119 is actually a bit higher up in the sky than the 101, but from your location it's probably actually closer to the horizon. To figure out where it really is, try the idea I gave Richard earlier:


You can probably extrapolate the sky position by taking the known figure that the receiver gives you for pointing a round dish, then taking the value for pointing an oval dish, and then continue the line across the sky in the same direction and the same quantity in number of degrees of az and elevation between those two settings, and this ought to point you at the 119.



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Andy
 

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Thanks Andy. I found a website that will convert my address to my Lat. and Long. Using that information instead of my zip code, the aiming information reported back were a bit different. The tilt is the only thing I haven't messed with yet. Currently I have it set at 66. (Per the Zip code aiming info.) The Lat/Long reports back that it should be tilted at 63. At the moment were under a severe weather alert. I'll have to wait to get back up on the roof. BTW, Not to confuse things, but, when I go to the installation menu for the Mits and run "Autoconfig" its not decting the B LNB. In fact it reports back that I have a round dish. Could this little hiccup ba an issue?


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M. Maylock
 

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The way a receiver "auto-configures" the dish is to tune to each LNB and listen for usable signal. There's nothing about the system that allows the receiver to detect an LNB connected that isn't receiving a good signal. So the assumption is that the dish is already installed correctly.


What this really says is that unless the dish is installed correctly and getting a valid signal, auto-config is useless - as in your case. You'll need to tell it manually that you have an oval dish so that you can get access to the Sat B signal meter so you can play around with your dish. Typically the numbers from the receiver are reasonably accurate - at least, good enough as a starting point.


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Andy
 

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Thanks again Andy. When the weather today/tomorrow clears I'll try tweaking the tilt. Of all things: My aiming is right at the top of a small clump of tall trees in my neighbors yard. It concerns me that the 119 might be closer to the horizon meaning closer to the trees. Well, a little more fun on the ladder tomorrow!! I'll post my results. http://www.avsforum.com/ubb/smile.gif


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M. Maylock
 

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From the East coast, the 119 satellite will be six - seven degrees elevation below the elevation of the 101 satellite. The tilt value is critical, set it according to the value in the setup screen of your Plus receiver and don't change it for the duration of the set up.


The 119 is (surprise) eighteen degrees further West than the 101, and (as mentioned)lower on the horizon. Calculations for DirecTV's 110 satellite are usually unnecessary because if the 101 is on, and the 119 is on, the 110 is on (except perhaps tweaking it's seating in the mount).



Good Luck


Scott
 

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Thanks Scott. Is the tilt setting derived from the lat/long better than using the zipcode? You mention that it's critical for alignment. Using my zipcode it shows 66 degrees, using the lat/long is shows 63 degrees. Also, how much lower on the horizon would you estimate the 119 bird to be? FYI my lat/long based settings are AZ 225, El 34 and Tilt 63. Using my zipcode they are AZ 218, El 35 and Tilt 66. Anyone who wants to try setting their dish aiming coordinates by translating their address to lat/long coordinates can find it at: http://www.geocode.com/eagle.html-ssi


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M. Maylock
 

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Discussion Starter · #16 ·
I recently upgraded my old RCA DirecTV plus receiver to a Toshiba DST-3000 HD STB. Since I already had the plus system for about a year or so, I already had the correct Dish and LNBs. Actually I have all three as I get local channels via 110.


I have been able to watch things such as NASA channel and HD demo loop/PPV on 199 on both the old and new receiver. I only recently subscribed to HBO (to get Channel 509). However, before I subscribed to HBO, I noticed I was not getting the 199 demo loop. I didn’t think much about it, until I also didn’t get NASA or 509. So I check my signal strength for 119 and I had no signal. Both the 101 and 110 were high (above 80 or 90).


Ok, My first thought was that it was spring and that the neighbor’s trees that I have been battling have finally grown enough to block out the 119 satellite. I have already moved my dish three times over that past few year due to neighbors trees the eventually grow enough to block my line of sight.


I climb up on my roof to check to make sure it is not a bad connection, LNB, etc. During this time, I was planning on swapping out the 101 and 119 LNB (to make sure the LNB was not bad). During this time, I had all three LNBs dangling loose, but connected by their cables. My wife yelled and said that I was getting a signal for 119. It was weird in that I had the 119 LNB in about the position for the 101 LNB. I was unable to figure out why I had such good signal for 101 and 110, but if I had the 119 LNB in the vicinity of the slot on the arm for the 101, I received a signal.


I assumed at this point that it probably was not a bad LNB or cable (I was getting a signal), and that it might have still be a problem with the neighbors trees. I was also getting tired of doing the dance on a hot and steep roof and decided it might be time to move the antenna to an easier to deal with location.


I did a survey of my front yard and found a spot that shot over the neighbor’s house and missed their trees. I spent all day yesterday digging a ditch and hole, running conduit, pouring concrete, etc. All to be back exactly where I was on Saturday. I let the concrete set last night and mounted the dish this morning. Great signal on 101 and 110, but between 0 and 10 on 119 (some signal at least).


I did a search on this Forum for 119 issues and I have some ideas (check cables, bypass multiswitch and connect directly to 119 LNB, etc.). I did notice that people seemed to have azimuth and elevation values for all three satellites. I am curious how they found/calculated those. I suspect that with my tilt setting, that I might be back into a tree or the neighbor’s roof with the 119 satellite.


I live on the east coast (North Carolina) and my zip code is 27703 if anyone can provide the values for my location. I assume that info stuff my receiver provides (azimuth and elevation) is probably for the 110 satellite (since it is roughly in the middle of 101 and 119)


A few other things to note. I did all of my pre-‘plus’ dish installs. When the three LNB dish was installed for the ‘plus’ system, it was part of a free install package (DirecTV local channel customer retention package), so I have no experience with three LNB alignment. I also still have my old dual LNB dish from my first Receiver, so setting up a second dish is a possibility. I might even mount it on a sled in the short term to see if I can find a spot that the 119 works.


Any help is appreciated.


Richard
 

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Quote:
Originally posted by Richard Casto:
I live on the east coast (North Carolina) and my zip code is 27703 if anyone can provide the values for my location. I assume that info stuff my receiver provides (azimuth and elevation) is probably for the 110 satellite (since it is roughly in the middle of 101 and 119)
Richard, see the information below to use the sun to check for a clear shot at the satellites. Conversely make sure there are no shadows near the dish. Use the info from your receiver for azimuth, elevation, and tilt settings. The info in your receiver is magnetic bearings, while my info is true North.


If west declinations are assumed to be negative while east declination are considered positive then True bearing = Magnetic bearing + Magnetic declination. For the 101° satellite -215.2 + (-8) = 223° Magnetic, for 110° satellite -226.2 + (-8) = 234° Magnetic, and for 119° satellite -235.5 + (-8) = 243.5° Magnetic.


Your longitude in degrees:78.6

Your latitude in degrees:35.8

Time Zone: Eastern


Longitude of Satellite in degrees:101

Azimuth of Satellite: 215.2°

Elevation of Satellite: 42.1°


Tuesday, April 24, 2001

Sun is 21.2° above sat position at 2:14pm EDT.


Saturday, April 28, 2001

Sun is 22.7° above sat position at 2:10pm EDT.


Saturday, May 5, 2001

Sun is 25.1° above sat position at 2:05pm EDT.


Longitude of Satellite in degrees:110

Azimuth of Satellite: 226.2°

Elevation of Satellite: 36.9°


Tuesday, April 24, 2001

Sun is 23.1° above sat position at 2:39pm EDT.


Saturday, April 28, 2001

Sun is 24.7° above sat position at 2:35pm EDT.


Saturday, May 5, 2001

Sun is 27.3° above sat position at 2:27pm EDT.

Longitude of Satellite in degrees:119

Azimuth of Satellite: 235.5°

Elevation of Satellite: 30.7°


Tuesday, April 24, 2001

Sun is 25.1° above sat position at 3:06pm EDT.


Saturday, April 28, 2001

Sun is 26.9° above sat position at 3:00pm EDT.


Saturday, May 5, 2001

Sun is 29.8° above sat position at 2:51pm EDT.



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Wendell

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MAETV
 

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Assuming you're using an oval dish, and you tell the receiver that you're using an oval dish, the numbers it will give you for Az/Elev/Tilt are correct to receive all satellites. You'll note that if you tell it you have a round dish, the numbers will change to point directly to the 101 satellite and will be significantly different from the values it supplies for an oval dish (most notably no tilt adjustment supplied at all for round dishes, obviously.)


If that's the case for you, then trust what your receiver's telling as a starting point for oval dish aiming.


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Andy
 

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Discussion Starter · #19 ·
First, I want to thank everyone for their help.


When I did my survey this past weekend, I thought that I could fit the 18 deg spread from 101 to 119 within a window between the trees and over the neighbor’s roof. I also thought that I had centered the 110 satellite right in the middle of this 'window'.



This morning, with the actually magnetic azimuth and elevation values for the 119 satellite, I discovered that my original site survey sucked. http://www.avsforum.com/ubb/frown.gif


I was under pressure to get everything done in one day (set new post, run conduit, move dish from roof, etc) and now everything is a few feet to the right too far. So, for 119, I am pointing into the neighbor’s tree (yet again).


So at this point I am going to explore setting up another dish just for 119 (wife not happy about this) or trying to see if I can relocate the main dish to pick up all three. The last option of sneaking into the neighbors yard and cutting down the 60'+ tree in his back yard when he is at work is probably not a good option.


Richard
 

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Discussion Starter · #20 ·
Quote:
Originally posted by Wendell R. Breland:
Richard, see the information below to use the sun to check for a clear shot at the satellites...... chop
Wendell,


Thanks for the info! I assume you didn't calculate this by hand. Do you have a URL for either the online 'calculator' you used for this or is there free/shareware software that I can download for this type of calculation?


Richard

 
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