NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Calculators for Navigation
From: T Tom
Date: 1999 Mar 17, 22:38 EST
From: T Tom
Date: 1999 Mar 17, 22:38 EST
Dan, Thanks for the help now I get to learn how to actually make my calculator work, now where did I put that manual. This is also a sort of test post as I seem to have a problem with my mail being cross posted Talk to you again soon. Tom "Daniel K. Allen (Visual C++)" wrote: > You can easily program in the sight reduction formula into an HP19BII or any > other HP calculator with HP Solve. This is, of course, just the law of > cosines: > > Spherical Trig Law of Cosines > cos(a)*cos(b) + sin(a)*sin(b)*cos(ab) = cos(c) > > and then you can use it to solve both great circle distance calculations and > sight reduction by the following use of a, b, ab, and c: > > For Great Circle Distance Computations: > a = 90 - lat1, b = 90 - lat2, ab = lon2 - lon1: c*60 = distance in nmi > b = c, c = b, recalc and ab = inital course > > For Celestial Nav Sight Reduction: > a = 90 - estLat, b = 90 - decl, ab = LHA = GHA - estLong, 90-c = altitude > b = c, c = b, recalc, and ab = azimuth (360-az if lha < 180) > > Dan > > -----Original Message----- > From: Titanium Tom [mailto:titom@XXX.XXX] > Sent: Friday, March 12, 1999 7:29 PM > To: Daniel K. Allen (Visual C++); Daniel K. Allen (Visual C++) > Cc: 'Mike Wescott'; Dan Hogan; navigation@XXX.XXX > Subject: Re: [Nml] Calculators for Navigation > > Dan, > My calculator that I presently use is an HP19BII, Buisness Consultant II > which has RPN also. Do you think that I will be able to use it for what I > will > need for our purposes here on Silicon Sea II ? > Thanks for the help. > T Tom. > > Daniel K. Allen (Visual C++) wrote: > > > Personally I prefer to spend my time doing lots of programming on my > HP-48GX > > to get sight reduction to the fewest keystrokes! The HP 48 uses very > little > > power and has great built-in functionality. It has a strange programming > > language called RPL (Reverse Polish Lisp) but it is quite powerful. Sadly > > HP is doing very little with calculators any more. > > > > My best nav programs are written in the C programming language and run on > my > > laptops, although I am about to port them to a small HP620LX Windows CE > > machine... which is what HP is putting its efforts to now. At least these > > machines can be programmed in C -- a big step forward -- but they do not > > support much programming on the machine: you need to write the programs on > a > > desktop machine running Windows 98 or NT. > > > > I've begun experimenting with some nav software written as an Excel > > spreadsheet, and it actually works quite well. These Handheld PCs that > run > > Windows CE (like the HP620LX and their newer Jornada) have a Pocket Excel > in > > ROM and one CAN program on the handheld machine in Excel simply by writing > > formulas. (No macros or VBA yet though.) > > > > One of the great advantages of using Excel for numerical calculations is > > that you can see as much of your intermediate results as you want along > the > > way. You can change just one variable and see how it affects the answer, > > etc. Writing nav software using Excel is actually pretty promising! > > > > Dan > > danallen@XXX.XXX > > > > -----Original Message----- > > From: Mike Wescott [mailto:mike.wescott@XXX.XXX] > > Sent: Friday, March 12, 1999 6:18 AM > > To: Titanium Tom > > Cc: Dan Hogan; navigation@XXX.XXX > > Subject: Re: [Nml] Silicon Sea II: Show of Hands > > > > > What type of calculator is the best for working the calculations, should > > it be > > > programable? > > > > Personally, I prefer minimal computer help for doing the Silicon Sea > > problems > > (and maximal help on the open sea). I use a simple calculator and plotting > > sheets. If I weren't too lazy to use an Ageton method (or one of it's > > relatives, > > I would do without the calculator. > > > > -- > > -Mike Wescott > > mike.wescott@XXX.XXX > > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= > =-= TO UNSUBSCRIBE, send this message to majordomo@XXX.XXX: =-= > =-= navigation =-= > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-= TO UNSUBSCRIBE, send this message to majordomo@XXX.XXX: =-= =-= navigation =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=