(45) Moon AZEL

10302019, 05:16 PM
Post: #1




(45) Moon AZEL
MOON AZEL ROUTINE FOR HP45
Allowing for Parallax (May also be used for Great Circle bearing and distance calculations) G.D. Wall ZE2KV "Moon AzEl Calculations Preliminary: (a) Longitude to STO 1 (degrees and decimals). Longitude East positive, West negative. (b) Colatitude for North elevated pole to STO 2 (degrees and decimals). Colat for northern latitudes = 90  Lat Colat for southern latitudes = 90 + Lat (c) Horizontal Parallax to STO 3 (degrees and decimals). Obtain from the Nautical Almanac Routine: Read in GHA (DMS) DMS+ RCL 1 + *Note if less than 360 COS RCL 2 SIN STO 4 × 90 ENTER Read in DEC (DMS} North positive South negative DMS→ STO 5 SIN × RCL 2 COS STO 6 RCL 5 COS STO 5 × + ENTER COS⁻¹ ENTER (STO 8) SIN STO 7 RCL 3 × + CHS 90 + Read Elevation x⇄y RCL 6 × CHS RCL 5 + RCL 4 RCL 7 × COS⁻¹ If less than 360 Read Azimuth otherwise proceed CHS 360 + Read Azimuth At Test Point * less than 360 means values of 180 through 270 to 360, and negative values through 90 to 180 Test: Location 36°45'40" N; 119°47'10" W Horizontal Parallax 56.4' GHA 85°33.6' Declination 13°21.2' S Read: Elevation 29.61° Azimuth 140.61° Great Circle calculations: 1. Home station data is entered into STO 1 and STO 2 as before. STO 3 is zero. 2. Enter the longitude of the distant point at GHA but with reversed sign, i.e., Long 120 W = 120 Long 50 E = 50 3. Enter the latitude of the distant point at DEC. Positive for North latitudes, negative for South. 4. Great Circle angular distance is stored at STO 8 for future use. 5. Bearing of the distant station is read at Azimuth. 6. Great Circle distance is then obtained: RCL 8 69.057 × Read (in miles) RCL 8 111.14 × Read (in kilometers) 7. Part of the parallax correction routine is not used in the Great Circle calculations and may be omitted. Miss out the steps (RCL 3 ..... .. Read Elevation xy) but roll down twice after STO 7 and before RCL 6. Test: Fresno 36°45'40" N; 119°47'10" W to Salisbury, Rhodesia 18°S; 31°E Read: Bearing 62.77° Distance 10235 miles" BEST! SlideRule 

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(45) Moon AZEL  SlideRule  10302019 05:16 PM

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