(comp.sources.hp48)
Author:  [Robert Irving]
Subj:    CELESTIAL & DR NAVIGATION
         Version:   3-3 Rev A **
         Checksum:  # 4BC9h
         Bytes:     8775.5  (8778.5 for CELDRNAV.SRC)
Date:    24 Jan 1993
Keywords:  Celestial, Navigation, Dead-reckoning, Position
Telephone:  (818) 767 9740

** This revision corrects a logical statement error in Program 
STRN.  STRN corrected checksum is # 130h and bytecount is 2323.
All other programs were correct as transmitted.

These programs are SHAREWARE.  Copyright (C) 1993 by Robert
Irving.  See end of document for conditions on use.

I suggest that the DIR name 'CELDRNAV' be changed to 'NAV'
before transfer to the HP48.  Bytecount will be 8770.5.

PROGRAMS

CNT             A single-key CONTinue.
# 5762h     12.5

CONV            Converts input in DDD.MMM (degrees.minutes
# AC27h     53.5   &tenths) to DDD.DDD (decimal degrees)

DRT             Dead-reckoning track from a non-celestial fix.
#ADD6h     553.5

NTIM/NTMN       Times of sight determined by pushbutton, and
# 1631h    237  body sextant altitudes entered by operator.  
# 97B4h    237  Entry of "999" calls sight reduction program.

RESET           Dead-reckoning track from a celestial fix.
# F28Bh    176

DRDIS           Display of last DR position (GCT, Lat, Long).
# 7044h    272.5

RANG            Redisplay of prior fix plot, display centered 
# 928Dh    133  at fix position, plot magnified by 3.2.

LZT             Display local zone time (HHMM.) and indicate
# 5422h    399.5  difference in local date from Greenwich date.

These principal programs are supported by subprograms:

LEGS            # 8EC8h    665.5
STRED           # 234Eh    542.5
STAR            # 6E00h   1430 
RNFX            # F44Eh    224.5
SNTR            # 8DABh    320
POSPLOT         # 22CAh    341.5
STRDN           # C290h    542.5
STRN            #  130h   2323

OBJECTS

CST1            List for Custom Menu used with Air Almanac
CST2            List for Custom Menu used with Nautical Almanac.
GMTZ            Number describing the Local Zone Time (LZT).
                This number is zero at Greenwich, increasing
                by one for each 15 degrees West and decreasing
                by one for each 15 degrees East in position.
                Enter #(LZT) 'GMTZ' STO before running programs.

OPERATION

All principal programs prompt in detail for the necessary input.
Programs NTIM, STRED, and STAR work with the Air Almanac, show-
ing appropriate prompts for the ephemeris inputs needed.  
Programs NTMN, STRDN, and STRN work similarly with the Nautical
Almanac.  Unused programs and associated list can be PURGED.  All 
programs provide a precision of better than 0.1'.  These programs 
were prepared primarily for the operator of a small ship (sailboat 
or powered yacht, with magnetic compass) not routinely using
celestial navigation.  Using these programs, one can take a 
round of sextant sights, and enter the necessary ephemeris 
data, without overlooking any necessary input.  Most voyages 
begin with Program DRT, since it accepts inputs from navigation 
fixes other than celestial.  Program RESET continues DR tracking 
after a celestial fix, to the next (celestial or non-celestial) fix.  

NOTICE  

The author has exercised due diligence in the preparation of 
these calculator programs.  The author has, in the handbook
available for purchase (See SHAREWARE below) made adequate  
explanations, including provision of instructions and 
CAUTIONs for proper use and WARNINGs as to the potential
results of misuse.  The author reserves the right to make 
improvements in these programs at any time, and without notice.

USE OF THESE PROGRAMS WITHOUT THE ASSOCIATED HANDBOOK IS VERY 
LIKELY TO LEAD TO SERIOUS ERROR.

The author makes no warranties, either express or implied, with 
respect to the software described herein, its quality, 
performance, merchantability or fitness for any particular purpose.
These programs are provided "as is".  The author shall 
not be liable for errors contained herein, nor for direct, 
indirect, incidental or consequential damages in connection with
the performance or use of the software described herein.

The author has no business or financial relationship with 
HEWLETT PACKARD. 

SHAREWARE

These navigation programs are a SHAREWARE product protected by 
Copyright.  They are neither Public Domain nor FREE software.
You may use these programs to determine if they are suitable for
your purposes, and you may make copies to give to others for the
same objective provided the copies include ALL the original 
material, including this document.  The author does not receive 
any fee from bulletin boards or other methods of distribution.  
The author is paid only when you make a direct payment to 
register your name with the programs.

If these programs are useful to you, please send a payment of 
$18.00 (US funds) to:  Robert Irving, 9234 Cayuga Avenue, 
Sun Valley, CA  91352-1303.  Telephone:  (818) 767 9740.

In return for your registration, you will receive the handbook,
including detailed instructions, CAUTIONs, and WARNINGs; an 
annotated source code; and a sample solution.  In addition, you
will be notified when revisions of the programs or the handbook
are produced, and advised of any similar new products developed.

 - - - - - - - - - - - - - CUT HERE - - - - - - - - - - - - - - 

TO:  ROBERT IRVING
     9234 CAYUGA AVENUE
     SUN VALLEY, CA  91352-1303

SUBJ:  REGISTRATION FOR CELDRNAV PROGRAMS 3-3

1.  I ENCLOSE PAYMENT IN THE AMOUNT OF $18.00 US FUNDS.  
ADD MY NAME TO THE LIST OF REGISTERED USERS, AND SEND ME 
A COPY OF THE CURRENT HANDBOOK FOR SUBJECT PROGRAMS.

                        NAME:  __________________________
                        STREET/APT:______________________
                        CITY/ST/ZIP:_____________________