Elevation and declination. Dazed and Confused.
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To prevent even more confusion to future readers, I have withdrawn this post.
See answer by Linuxman, several posts below.
It uses BUD-friendly terminology...
... not all of which I agree with, but you don't buck the establishment.
please disregard this text (as previously posted):
There is a picture on this page of Geo-Orbit showing you how to understand and measure elevation and declination.
Your elevation for your true south bird is you latitude.
That could be found with Google looking it up for your zip code.
Here is is as expressed by one of the many sat finder programs: 32° 34.458'
Or just to round it off, you could go with about 32½.
Let's take the corrected elevation and declination from the Geo-Orbit web site to set up your BUD.
Read the entire page, but then scroll down to the bottom chart, and find your answer.
Since your latitude is half way between 32 and 33, take your answer half way between the entries on the bottom chart:
I read it as about 33.1 degree elevation and 4.725 declination.
There is a satellite at 97 which you could use as your true south satellite to get oriented.
Here are some strong C-band signals to get aligned with.
If you're using Ku-band, then fine tune the dish with one of these signals.
See answer by Linuxman, several posts below.
It uses BUD-friendly terminology...
... not all of which I agree with, but you don't buck the establishment.
please disregard this text (as previously posted):
There is a picture on this page of Geo-Orbit showing you how to understand and measure elevation and declination.
Your elevation for your true south bird is you latitude.
That could be found with Google looking it up for your zip code.
Here is is as expressed by one of the many sat finder programs: 32° 34.458'
Or just to round it off, you could go with about 32½.
Let's take the corrected elevation and declination from the Geo-Orbit web site to set up your BUD.
Read the entire page, but then scroll down to the bottom chart, and find your answer.
Since your latitude is half way between 32 and 33, take your answer half way between the entries on the bottom chart:
I read it as about 33.1 degree elevation and 4.725 declination.
There is a satellite at 97 which you could use as your true south satellite to get oriented.
Here are some strong C-band signals to get aligned with.
If you're using Ku-band, then fine tune the dish with one of these signals.
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See...thats why I'm confused. Those numbers are different than I have been coming up with. I finally just wallked away and am taking a break. I wasn't trying to be lazy, I posted out of frustration. I'm sure others have been there.
I'm gonna read a bit. Its gotta be something simple.
I'm gonna read a bit. Its gotta be something simple.
Hey, maybe I entered your zip code wrong.
We all make mistakes!
What did you come up with, and what reference material did you use?
Also, please re-read my post above.
I tend to edit and fine tune, and add explanation when I write.
Often whole new paragraphs.
We all make mistakes!
What did you come up with, and what reference material did you use?
Also, please re-read my post above.
I tend to edit and fine tune, and add explanation when I write.
Often whole new paragraphs.
No, You are correct. I was using the dishpointer site. I was getting 52 degrees or so elevation but didn't know the declination. I'm going out now to give it a shot. 20 degrees high....yea...I can see why I couldn't hit anything.
I think that part of the confusion on this topic is that we tend to use two or three different meanings for the word "elevation". I really wish that we had an alternative word for the angle that the plane perpendicular to the rotation axis of our motors is relative to the south horizon. We tend to call this elevation. I used to try to call this inclination to avoid confusing it with the normal use of the elevation term, but since nobody else does this, I've slipped back into the elevation usage, but it is VERY confusing to people.
But the bottom line is that the "ELEVATION" used in Azimuth/Elevation context is NOT the same ELEVATION that we refer to with respect to the motor angle on motorized systems, and I think that tends to confuse people.
For the old style motorized alignment, the "elevation" used when finding your south sat is 90 minus your latitude. Many motors have an elevation scale and a latitude scale. The elevation scale is 90-lat. Of course, as mentioned below, it's better to use the modified declination table at geo-orbit page, but they also confuse elevation and latitude setting. Another way to think of it is that the latitude setting IS elevation relative to the north horizon, and the elevation is the elevation of the plane perpindicular to rotation axis relative to the south horizon.
ALSO.... the elevation OF the south sat, is the (90-lat) elevation minus the non-modified declination. I know, I confused it even more. Sorry, but just trying to show how confusing something relatively simple can be confusing to newcomers due to the fact that one word can mean several different things.
Now that I've confused everything, to get back to what my point was going to be, to explain why the dispointer type pages give a different answer for "elevation", is that the "elevation" we use for a motorized dish isn't aiming at the sat, but is a plane nearly parallel to the eqatorial plane, but above it by several thousand miles, and we have to look down to the sat by the declination angle.
To finally put this into actual numbers:
The actual elevation of the motor using Anole's numbers is :
90-33.1=56.9
now, the actual elevation of the south satellite is
56.9-4.725=52.175
I'm guessing that this 52.175 is probably close to the number that the dishpointer site gave.
Also, if you do 90 minus the real latitude, ie 90-32.5= 57.5, and 57.5 minus the NON-MODIFIED declination, ie 57.5-5.32=~ 52.18 Ie both modified and non-modified scales are related to the actual elevation of the south sat.
So what I'm trying to say is that we have 3 different meanings for elevation, but they all end up getting to the same numbers, but it can be very confusing.
I wish that we had three different terms to use for these 3 different elevation terms.
Sorry.... I know I've made this even more confusing, but I constantly see people confused by this, and just wanted to show how the different "elevation" numbers related.
But the bottom line is that the "ELEVATION" used in Azimuth/Elevation context is NOT the same ELEVATION that we refer to with respect to the motor angle on motorized systems, and I think that tends to confuse people.
I know what you're trying to say here, but I think it's confusing.
For the old style motorized alignment, the "elevation" used when finding your south sat is 90 minus your latitude. Many motors have an elevation scale and a latitude scale. The elevation scale is 90-lat. Of course, as mentioned below, it's better to use the modified declination table at geo-orbit page, but they also confuse elevation and latitude setting. Another way to think of it is that the latitude setting IS elevation relative to the north horizon, and the elevation is the elevation of the plane perpindicular to rotation axis relative to the south horizon.
ALSO.... the elevation OF the south sat, is the (90-lat) elevation minus the non-modified declination. I know, I confused it even more. Sorry, but just trying to show how confusing something relatively simple can be confusing to newcomers due to the fact that one word can mean several different things.
Now that I've confused everything, to get back to what my point was going to be, to explain why the dispointer type pages give a different answer for "elevation", is that the "elevation" we use for a motorized dish isn't aiming at the sat, but is a plane nearly parallel to the eqatorial plane, but above it by several thousand miles, and we have to look down to the sat by the declination angle.
To finally put this into actual numbers:
The actual elevation of the motor using Anole's numbers is :
90-33.1=56.9
now, the actual elevation of the south satellite is
56.9-4.725=52.175
I'm guessing that this 52.175 is probably close to the number that the dishpointer site gave.
Also, if you do 90 minus the real latitude, ie 90-32.5= 57.5, and 57.5 minus the NON-MODIFIED declination, ie 57.5-5.32=~ 52.18 Ie both modified and non-modified scales are related to the actual elevation of the south sat.
So what I'm trying to say is that we have 3 different meanings for elevation, but they all end up getting to the same numbers, but it can be very confusing.
I wish that we had three different terms to use for these 3 different elevation terms.
Sorry.... I know I've made this even more confusing, but I constantly see people confused by this, and just wanted to show how the different "elevation" numbers related.
Yes, That is correct. I am going to print everything off today and sit and read it all again and start over with my dish pointing procedure. Last night, I could peg 97, scan and had a few channels.(nothing I could really understand but at least a channel) If I motored west I could see the signal strenghts go up a few points, drop as I went west and go back up but never get anything on the quality strength. I think where I made the mistake is I lined up the dish with true south....and then moved the WHOLE dish, polar mount and all to 97 and then tightened up the polar mount and adjusted.
If I am understanding correctly, I should line up true south, tighten the polar mount, adjust elevation and declination angle THEN MOTOR over to 97 and tweak for best signal. Am I correct?
Yes, kinda.
Since you are in between Sat Locations at 96.2 west, like me at 87.9west, try to align the mount to your True South 176 using a compass. Then make sure the Dish is at it's Highest point in it's Arc, take you time with that.
Triple check that your Mount is on the Pole plumb!
Set your Elevation, then Declination.
Power up, and get a Live / Active TP up on the Receiver for 97west. You will probably get some Quality reading with out moving the Dish, but Driving the Dish to the West should improve the signal, count the pulses from where you started from to peak signal for 97 west.
To confirm you are aligned to you True South, you should be able to drive the Dish East the same number of pulses from center (true south) and get 95 west.
Thank you Lak7 for explaining this, I have never done C band but wander over here sometimes to see what is going on. My first temptation was to "correct" Anole after I checked the Zip and his elevation numbers. But he is seldom wrong - so I did some reading first.
VERY confusing! I did the math as you pointed out above and came up with Anole's numbers - but said why make it so complicated?
Bob
VERY confusing! I did the math as you pointed out above and came up with Anole's numbers - but said why make it so complicated?
Bob
better site than Geo-Orbit ?
Well I've had this discussion with Linuxman a few times, but his particular latitude makes the numbers even more confusing.
I know he can explain it more clearly. - :up
And speaking of the confusing usage of the language, I hate to see folks use the word "declination" to refer to the magnetic deviation from actual north on a compass.
That's only come up in the last couple of years.
They're not wrong, but I still want to slap 'em all!
Well I've had this discussion with Linuxman a few times, but his particular latitude makes the numbers even more confusing.
I know he can explain it more clearly. - :up
And speaking of the confusing usage of the language, I hate to see folks use the word "declination" to refer to the magnetic deviation from actual north on a compass.
That's only come up in the last couple of years.
They're not wrong, but I still want to slap 'em all!
I use Satlex Digital site for all my adjustments for Polar Mounts.
Here are the results for your zip code.
Azimuth angle: 181.30° (True North)
Elevation angle: 52.13°
LNB tilt (Skew): 1.10°
Offset angle: 0.00°
Distance to satellite: 36949.40 Km
Signal delay: 246.33 ms (Uplink + Downlink)
Declination angle: -5.29°
Polarmount hour angle: 180.80°
Angle setting on motor: 0.8° West
Satellite: Galaxy 19 (97° W) Closest to True South for you!
The confusion comes because the different sites and calculators use different terminology to define elevation etc.
Total Elevation includes the Declination Angle and the Total Elevation is measured on the back ring of the dish.
Total Elevation minus the Declination is measured on the "elevation" bar on the Polar Mount.
For you 52.13 minus 5.29 for an "elevation bar" setting of 46.84 degrees.
Once you have the declination of 5.29 degrees set between the "elevation bar" and the "ring back" don't ever move the declination setting again.
See Pic below:
Here are the results for your zip code.
Azimuth angle: 181.30° (True North)
Elevation angle: 52.13°
LNB tilt (Skew): 1.10°
Offset angle: 0.00°
Distance to satellite: 36949.40 Km
Signal delay: 246.33 ms (Uplink + Downlink)
Declination angle: -5.29°
Polarmount hour angle: 180.80°
Angle setting on motor: 0.8° West
Satellite: Galaxy 19 (97° W) Closest to True South for you!
The confusion comes because the different sites and calculators use different terminology to define elevation etc.
Total Elevation includes the Declination Angle and the Total Elevation is measured on the back ring of the dish.
Total Elevation minus the Declination is measured on the "elevation" bar on the Polar Mount.
For you 52.13 minus 5.29 for an "elevation bar" setting of 46.84 degrees.
Once you have the declination of 5.29 degrees set between the "elevation bar" and the "ring back" don't ever move the declination setting again.
See Pic below:
Thank you everyone for your comments. I think I have a grasp of it now. I have a "Johnson" angle finder. I am not sure how accurate it is. Can someone recommend a GOOD angle finder?
Linuxman...I have been reading some of your posts. There is an older lady about 40 miles from me that has given me what someone told her to be a set of "birdwire" dish's. She said she thought about laying them flat on the ground and filling them with water for birdfeeders. OH THE HORROR! One is larger than the other. Needless to say I'm gonna go check them out and see if they are signal suckers.
Linuxman...I have been reading some of your posts. There is an older lady about 40 miles from me that has given me what someone told her to be a set of "birdwire" dish's. She said she thought about laying them flat on the ground and filling them with water for birdfeeders. OH THE HORROR! One is larger than the other. Needless to say I'm gonna go check them out and see if they are signal suckers.
Take a camera and document what you find.
Shoot a picture or two with something of recognizable size in it, too.
Shoot a picture or two with something of recognizable size in it, too.
OK. I pretty much "assumed" they were birdview dishes. I re-read her email. She said she though about making them "gold fish ponds" but she didn't say whether they were metal or fibreglass. I just shot her another email for more details. She's an older woman so I'm not gonna ask her to measure. I will just go check them personally.
THANK YOU SATELLITE GUYS!
I fought this thing over 2 sundays. I finally decided I needed a good meter to peg this thing. (Probly just me but it works great!) I bought an AcuTrac 22 MKII Pro. Today, I shortened the pole by 30 inches and installed my leveler. (another thread) Reinstalled the BUD, leveled everything spot on. Set my elevation bar at 33.1 and declination to 4.725. Peaked at 97W, motored to extremes, push up and down, back to 97W, adjusted polar angle a bit, motored back to extremes, tweaked LNB. Now everything works great!
Is it "normal" to have a weaker signal on the extreme Sats? Specifically the far eastern sats. I "gently" pushed up and down on the rim of the dish while on the eastern extreme but it makes no difference. Actually gets worse either up or down so I figure I'm spot on. The western sats are better, again, signal gets lesser if I pull up or down on the rim of the dish.
I haven't actually connected a reciever to the dish yet. All of this was done with the Acutrac meter. I still might need to tweak, I dunno yet. Using the meter the far eastern sats will hit around 40ish.
I fought this thing over 2 sundays. I finally decided I needed a good meter to peg this thing. (Probly just me but it works great!) I bought an AcuTrac 22 MKII Pro. Today, I shortened the pole by 30 inches and installed my leveler. (another thread) Reinstalled the BUD, leveled everything spot on. Set my elevation bar at 33.1 and declination to 4.725. Peaked at 97W, motored to extremes, push up and down, back to 97W, adjusted polar angle a bit, motored back to extremes, tweaked LNB. Now everything works great!
Is it "normal" to have a weaker signal on the extreme Sats? Specifically the far eastern sats. I "gently" pushed up and down on the rim of the dish while on the eastern extreme but it makes no difference. Actually gets worse either up or down so I figure I'm spot on. The western sats are better, again, signal gets lesser if I pull up or down on the rim of the dish.
I haven't actually connected a reciever to the dish yet. All of this was done with the Acutrac meter. I still might need to tweak, I dunno yet. Using the meter the far eastern sats will hit around 40ish.
I'd check more than one transponder of the eastern satellites if those are the ones that are 'weaker'. I rarely move a c-band dish east of AMC3 here, but I do have 2 small fixed cband dishes in use, one's on AMC6 for NASA and the other is a 5' pointed at 58w , or maybe its 55w, hardly ever look at it lol. A big dish thats tracking right should yank in good signals across the arc. I feel for all you folks who never had it so easy- back in the earlier days, when the sats were all loaded with free analog channels, it was a piece of cake to roughly align to the arc back then.
Aww man . I ran all my cable yesterday, set up my box and found I was pointing at 103W instead of 97W. LOL! That explains allot. I have to go back and reset everything. THAT IS OK THOUGH! It's all a learning experiance for me and I'm really enjoying it. Thats what its all about aint it? I'm gonna buy a new compass because my old one is giving me fits. This time I'm gonna take everything outside with me. TV, Reciever, Actutrac...all of it. I think I can nail it pretty quick this time.
I think my GoeSat C/KU is dead on the C side....I cannot get ANYTHING at all from C side. KU I'm pegging 100 on quality on 103W. Maybe a skew problem? I am running the 2 feeds into a DiSeqc. Port 1 is KU, port 2 is C. Ku side if I connect the acutrac directly up I get at least 20-30 no matter what. C side connected directly to the acutrac I get 0 no matter what. ANyone ever heard of a bad GeoSat C/KU. I got it from Sadoun 2 weeks ago. Maybe I should start a new thread on it?
I think my GoeSat C/KU is dead on the C side....I cannot get ANYTHING at all from C side. KU I'm pegging 100 on quality on 103W. Maybe a skew problem? I am running the 2 feeds into a DiSeqc. Port 1 is KU, port 2 is C. Ku side if I connect the acutrac directly up I get at least 20-30 no matter what. C side connected directly to the acutrac I get 0 no matter what. ANyone ever heard of a bad GeoSat C/KU. I got it from Sadoun 2 weeks ago. Maybe I should start a new thread on it?
Try C Band with out a Switch (always unplug the receiver when connecting / disconnecting a switch)
C Band is much more forgiving than Ku.
C Band is much more forgiving than Ku.
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