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Thanks Gerson for making pgm readable! This pgm is designed to convert right ascenion & declination of any celestial body into simple altitude and azimuth. You therefor need to make/copy /draw a 360degree az circle on the mount base and a 0 to 90 degree scale for alt, 0 being level, 90 pointing straight up. Marking every 10 degrees is sufficient since its easy to interpolate. The # 6.619 is a constant and changes yearly, for2008 = 6.603, for 2009 =6.654. U is GMT for Calif, 10PM this August =5.0 , when daylight sav ends it is 6.0, use decimal minutes, 9:30 PM= 4.50 GMT. Latitude & longitude of your site are decimal degrees. Day number - add date to this # so for August 20= 212 + 20 = 232. Jan=0,Feb=31, March = 59, April=90, 120, 151,181, 212, 243, 273, 304, and 334 for Dec. Right & declination are also input in decimal degrees. To get accurate results, the scope must be LEVEL- I mounted a bullseye level on my portable scope which works well. Sight Polaris [north star] and set Az to read 0 degrees, use a red light preserves nite vision ], look up RA & Dec of object, run pgm to get alt/az and slew scope to these coordinates. Use a widefield-low power eyepiece initially since there is a 1 to 3 degree offset in position-slowly slewing from the calculated position will locate object quickly. One really appreciates this pgm with objects 0ver 50 degrees high-no more on your knees squinting up while your back complains. Howard

Part 2 addendum ; For leap years, add 1 day to D starting with March thru December. Howard

Perhaps these time and date routines might be useful somehow. They should be adapted to your needs and converted to the HP-35s, in order to save labels. They are based on a program that came in the Master Library Module, for the TI-58/59.

Regards,

Gerson.

DATE & DAYS BETWEEN DATES ROUTINES (HP-33S VERSION)

G0001 LBL G
G0002 x<>y
G0003 STO A
G0004 x<>y
G0005 ENTER
G0006 IP
G0007 STO C
G0008 Rv
G0009 RLC C
G0010 -
G0011 100
G0012 *
G0013 ENTER
G0014 IP
G0015 STO B
G0016 Rv
G0017 FP
G0018 4
G0019 10^x
G0020 *
G0021 STO D
G0022 2
G0023 ENTER
G0024 RCL C
G0025 x>y?
G0026 GTO H
G0027 RCL D
G0028 1
G0029 -
G0030 100
G0031 /
G0032 1
G0033 +
G0034 IP
G0035 0.75
G0036 *
G0037 IP
G0038 +/-
G0039 RCL D
G0040 1
G0041 -
G0042 4
G0043 /
G0044 IP
G0045 +
G0046 RCL C
G0047 1
G0048 -
G0049 31
G0050 *
G0051 +
G0052 RCL B
G0053 +
G0054 RCL D
G0055 365
G0056 *
G0057 +
G0058 RTN

H0001 LBL H
H0002 RCL D
H0003 365
H0004 *
H0005 RCL B
H0006 +
H0007 RCL C
H0008 1
H0009 -
H0010 31
H0011 *
H0012 +
H0013 RCL C
H0014 0.4
H0015 *
H0016 2.3
H0017 +
H0018 IP
H0019 -
H0020 RCL D
H0021 4
H0022 /
H0023 IP
H0024 +
H0025 RCL D
H0026 100
H0027 /
H0028 1
H0029 +
H0030 0.75
H0031 *
H0032 IP
H0033 -
H0034 RTN

N0001 LBL N
N0002 XEQ G
N0003 RCL A
N0004 XEQ G
N0005 RCL A
N0006 -
N0007 +/-
N0008 RTN

W0001 LBL W
W0002 XEQ G
W0003 ENTER
W0004 +/-
W0005 7
W0006 /
W0007 IP
W0008 7
W0009 *
W0010 +
W0011 RTN

Length & Checksum Table:

LBL CK LN
G 7A9E 318
H 75E1 210
N E3B8 24
W 3A2B 57

Usage:

date 1 (MM.DDYYYY)
ENTER
date 2 (MM.DDYYYY)
XEQ N => number of days between dates

date (MM.DDYYYY)
XEQ W => weekday (0=Sat, 1=Sun, ... , 6=Fri)

yes, you could use this for the day # however the best help would be an internal clock for the time input which means you only have to input Right Ascenion & Declination and dont have to check your watch before input of each object. Howard