AstroNav - using a calculator or laptop

[stephenh]

Pugwash60 - I have PM'ed you.

 

[PetiteFleur]

I have a Casio fx-3900 Pv Scientific Calculator - apparently already programmed to suit. I must be honest and admit I've never used it - I bought it at a local auction together with a Davis sextant and several books, articles etc. Originally sold by Reed's Nautical Bookshop as a package.
One day I'll get round to trying it out.........

 

[maxi77]

This is more of a moan than anything , but I've always used a simple scientific calculator and punched in the numbers for the spherical cosine formula for doing the basic sight and then used abc tables for the azimuth. My moan relates to modern calculators which I find to be a complete pain in the @@@. The old ones essentially allowed you to use whatever number was in the display and if you wanted the cos or sin of it you just pressed cos or sin or whatever, now you have to put it into a memory then press cos or sin and then bring it out of memory which is so ridiculous it makes you want to cry. I was so cross I ended up buying an HP at huge expense which uses reverse osmosis or something as a operating logik and it would be brilliant except that it doesn't manage to do degrees minutes and decimals of a minute. You can get around it by doing degrees and so many hundreds divided by 600 thereby fooling it but I'm amazed that it can't manage degrees and minutes when even the cheapest of chinese calculators can do that. There is a perverse pleasure in having the HP which people not in the know are unable to make work. Am I the only one who hates these modern calculators. I wish I still had my old Casio fx which was beautifully predictable.
Moan over.

The good old HP RPN (reverse polish notation) as you say a very perverse way of doing your maths, but HP as well as weird mathematitians had very good marketeers and sold the system by getting lots of free software written for engineers and publishing it in all the trade magazines. Engineers then selected the HP calculators over the superior TI ones, and the rest is history.

 

[JayBee]

Most, if not all Casio programmable calculators work in algebraic logic instead of RPN.

Here's one that should be simple to load up with sight reduction formulae:

http://edu.casio.com/products/program/fx4500pa/closeup_4500pa.html

and there are many others.

 

[pugwash60]

Once you get used to it the HP with rpn is approximately a million times easier to use for longish calculations than the normal style ones from the 80's and more like a billion times easier than the ones made today I can't believe that teachers and lecturers aren't gettting their students to get hold of the older calculators which would in turn get the Casios of this world back to making more sensible to use calculators instead of the ones they now produce which try to get you to put things in in the order that they would be written, and produce a stupid message if you put in x first by mistake and then / later without first having erased the x. On the old ones it pretty much didn't matter which arithmetic function buttons you pushed as long as the last one you pushed was the one that you meant.

 

[JayBee]

Once you get used to it the HP with rpn is approximately a million times easier to use for longish calculations than the normal style ones from the 80's and more like a billion times easier than the ones made today I can't believe that teachers and lecturers aren't gettting their students to get hold of the older calculators which would in turn get the Casios of this world back to making more sensible to use calculators instead of the ones they now produce which try to get you to put things in in the order that they would be written, and produce a stupid message if you put in x first by mistake and then / later without first having erased the x. On the old ones it pretty much didn't matter which arithmetic function buttons you pushed as long as the last one you pushed was the one that you meant.

Thought you were having a moan about HP and RPN.

You did say you wished you had your old Casio fx!

The Casio will also do degrees, minutes and decimals, no probs, and you just input the formula as it is written. No need to store anything unless it is an instruction in a program and a one off exercise.

 

[pugwash60]

No just a general moan about modern calculators, my first calculator was something like a casio fx19 which I found fine, I suppose I learned how to use it, later ones seemed to get progressively irritating by trying to be clever. I love the HP except for its not having the ability to do degrees and minutes easily which most cheap calculators can do without hassle. The hp can do degrees and minutes but can't handle decimals of a minute which is why I ended up having to use the fraction key and do the degrees followed by three digits for the minutes and decimals of a minute and put it over 600, it works but is awkward. The thing has far more capability than I use but it's fine.