# Have I calculated azimuth correctly?

#### bertbarndoor

##### SatelliteGuys Pro
Original poster
Hi, I am wondering if my coordinates are correct? I want a Dish 500 for 110 & 119 and a Dish 300 for 61.5

I am at 45° 19' N & 75° 40' W

Dish 500: 22.7 Elevation, 233.3 Azimuth (+14 magnetic = 247.3 compass), 34.4 skew

Dish 300: 36.2 Elevation, 160.8 Azimuth (+14 magnetic = 174.8 compass), -13.4 skew

I need to do a dish placement site survey to see if this will work. If someone could verify that would be great. Mostly, I am worried about going from Azimuth to magnetic on my compass. Thanks! -Rob (getting closer to jumping in the deep end)

It looks correct for the Dish 300. You don't have to worry about skew for the DISH300 since you only have one LNBF on it and the signal is circular
Yes the addition of the magnetic deviation is correct as well.

bertbarndoor said:
Hi, I am wondering if my coordinates are correct? I want a Dish 500 for 110 & 119 and a Dish 300 for 61.5

I am at 45° 19' N & 75° 40' W

Dish 500: 22.7 Elevation, 233.3 Azimuth (+14 magnetic = 247.3 compass), 34.4 skew

Dish 300: 36.2 Elevation, 160.8 Azimuth (+14 magnetic = 174.8 compass), -13.4 skew

I need to do a dish placement site survey to see if this will work. If someone could verify that would be great. Mostly, I am worried about going from Azimuth to magnetic on my compass. Thanks! -Rob (getting closer to jumping in the deep end)

Your setting for the 300 dish is right for elevation and azimuth.

The setting for the 500 dish is off.

Use : elevation - 25.4 azimuth - 241 skew - 122

Note the skew setting is quite different for the 500 than your calculations.

Last edited:
Clancy said:
Your setting for the 300 dish is right for elevation and azimuth.

The setting for the 500 dish is off.

Use : elevation - 25.4 azimuth - 241 skew - 122

Note the skew setting is quite different for the 500 than your calculations.

Just out of curiosity, what did you use to calculate the 500? I used Sadoun's site. (Thanks Sadoun!) Maybe I messed it up. Do you use 119 or 110? Thanks. :tux:

Here's the rocket science of it.

Sadoun's site is for a single LNBF antenna. Therefore, for the Dish 500 which is a dual LNBF, you can do 1 of two things to get you in the ball park.
...(1) Run the calculations for 110, then run the calculations for 119, and then take the middle setting for each of the calculations; or the easy way,
...(2) Adjust the Satellite location to 114.5 which is middle way between 110 and 119.

Doing it the second way for Ottawa:
...Elevation = 25.3
...Azimuth = 228.5 True
...Skew = 31.7

However, with the Dish 500, the Skew setting of 90 actually = 0 degrees.
Therefore, Skew +31.7 = 121.7 on the Dish 500.

So 25.4 or 25.3 for elevation - you'll never eye it that much on the scale; and likewise, 121.7 or 122 for the Skew can not be adjusted that close, and since you adjust it first - you will pick up the slack with the Elevation and Azimuth.

EDIT: Also, I used Sadoun Ottawa setting which is Lat 45.4N and Long 75.7W; instead of your 45-19N (45.31N) and 75-40W (75.66W). Close enough.

Last edited:
SmityWhity said:
Here's the rocket science of it.

Sadoun's site is for a single LNBF antenna. Therefore, for the Dish 500 which is a dual LNBF, you can do 1 of two things to get you in the ball park.
...(1) Run the calculations for 110, then run the calculations for 119, and then take the middle setting for each of the calculations; or the easy way,
...(2) Adjust the Satellite location to 114.5 which is middle way between 110 and 119.

Doing it the second way for Ottawa:
...Elevation = 25.3
...Azimuth = 228.5 True
...Skew = 31.7

However, with the Dish 500, the Skew setting of 90 actually = 0 degrees.
Therefore, Skew +31.7 = 121.7 on the Dish 500.

So 25.4 or 25.3 for elevation - you'll never eye it that much on the scale; and likewise, 121.7 or 122 for the Skew can not be adjusted that close, and since you adjust it first - you will pick up the slack with the Elevation and Azimuth.

EDIT: Also, I used Sadoun Ottawa setting which is Lat 45.4N and Long 75.7W; instead of your 45-19N (45.31N) and 75-40W (75.66W). Close enough.

Thanks SmityWity! Very informative post! I was kind of wondering about that for a good chunk of the day!!! Now that I think about it, it makes total sense.

Cheers,

Rob

Latitude 45° 19.000'N Longitude 75° 40.000'W

-------------------------------------------------------------------------------------------
>>>>>>> NOTE: Calculate Skew values from 90 degrees West <<<<<<<
>>>>>>> Remember most DBS Dishes have 22.5 Degree offset <<<<<<<
-------------------------------------------------------------------------------------------

*** DBS Satellites ***

Sat Name Sat Lng Az(t) Az(m) El Skew
EchoStar 3/Rainbow 1 61.5W 160.5 175.1 36.0 -13.6
EchoStar 4 77.0W 181.9 196.5 37.8 1.3
EchoStar 6/8/10 110.0W 223.8 238.5 27.8 29.2
DISH 500 110/119 114.5W 228.5 243.2 25.4 31.8
EchoStar 7/7S 119.0W 233.0 247.7 22.7 34.2
DISH 1000 119.5W 233.5 248.2 22.4 34.4
EchoStar 9 121.0W 234.9 249.6 21.5 35.1
DISH 500 119/129 124.0W 237.7 252.3 19.7 36.5
EchoStar 5 129.0W 242.1 256.8 16.5 38.4
EchoStar 1/EchoStar 2 148.0W 257.2 271.9 3.6 43.3
EchoStar 4 157.0W 263.8 278.5 -2.6 44.4

DirecTV 1 72.5W 175.6 190.2 37.7 -3.1
DirecTV Spaceway 2 99.2W 211.5 226.2 32.8 21.5
DirecTV 2 100.8W 213.4 228.1 32.2 22.8
DirecTV 1R/4S/8 101.0W 213.7 228.3 32.1 22.9
DirecTV Spaceway 1 102.8W 215.8 230.5 31.3 24.3
DirecTV 6 109.5W 223.3 238.0 28.1 28.8
DirecTV 5 110.0W 223.8 238.5 27.8 29.2
DirecTV 7S 119.0W 233.0 247.7 22.7 34.2

Nimiq 2 82.0W 188.9 203.5 37.4 6.2
Center 86.5W 195.1 209.7 36.7 10.5
Nimiq 1 91.0W 201.1 215.8 35.6 14.7
Nimiq 4i 91.1W 201.2 215.9 35.6 14.7

Anik F1/F1R 107.3W 220.9 235.6 29.2 27.4
StarChoice 75cm Dual LNB Dish 111.1W 225.0 239.7 27.2 29.8
Anik F2 111.1W 225.0 239.7 27.2 29.8

Clancy said:
Your setting for the 300 dish is right for elevation and azimuth.

The setting for the 500 dish is off.

Use : elevation - 25.4 azimuth - 241 skew - 122

Note the skew setting is quite different for the 500 than your calculations.

Add 90 degrees to his number and its essentially what you and I posted. I have not looked at it in a while but remember that some DBS markings on their units for North America key off 90 degrees West.

Last edited:
bertbarndoor,

I have no doubt that the list from HDTVFanAtic is correct, but I did glanced over a couple of his settings to make sure. So, all of the above info from everyone is correct as stated.

The slight difference between mine and their's are the reference points for your location. You should use whichever location is most accurate for you, the set coordinates for Ottawa, or 45-19-00N x 75-40-00W, or maybe something else if you are on the NY state line. In either case, if it is only a 1/10 off, you can't measure that, and you are going to fine tune the the elevation and azimuth once you locate the signal.

The most important thing with this rocket science is -- MAKE SURE THE MAST IS PLUMB.

SW
ps - A couple of 622's should be good in the motor home.

Just to reiterate what SmityWhity, you can use the look angle calculator on our website to calculate the azimuth and elevation for a dish 500. Here is the easy and simple way to do that:

For Satllite Longitude use: 114.5 (which is the middle point for 110 & 119)
Select your USA city or enter you longitude and latitude

As for the results, use the following
Elevation: Use the results as is
Azimuth: Result +/- the magnitic deviation based on our location
Skew: Result + 90 degrees