The Museum of HP Calculators

HP Forum Archive 13

 HP33SMessage #1 Posted by Iqbal on 22 Aug 2003, 5:04 p.m. http://www.hpcalc.org/images/datasheet33s.pdf If you look at the dimensions of the 33S the metric dimensions doesn't correspond to the Imperial. 16.1 mm is definitely not equal to .06 inch [width] at least not on my GX. I wonder if they used the 33S to do this conversion. If in fact they did, then I think I just discovered the HP33S's first bug :)

 You're mean...Message #2 Posted by Vieira, Luiz C. (Brazil) on 22 Aug 2003, 5:14 p.m.,in response to message #1 by Iqbal Hello, Iqbal; long time no see... are you well? I sent you an e-mail for these days; did you receive it? About the HP33S: you're mean... It's not yet born and you're slapping it already! Best regards!

 Re: HP33SMessage #3 Posted by Nelson M. Sicuro (Brazil) on 22 Aug 2003, 6:16 p.m.,in response to message #1 by Iqbal I think that 16.1mm IS 0.06 inch. 0.161cm / 2.54 = 0.0063385826 inch I'm just curious how do you have converted it. Best regards. Nelson

 Re: HP33SMessage #4 Posted by bill platt on 22 Aug 2003, 6:37 p.m.,in response to message #3 by Nelson M. Sicuro (Brazil) 1 inch = 25.4 mm 1 inch = 2.54 cm the calculator is 16.1 mm = .634 inches I am trying to see if the mistake was made by confusing centimeters with millimeters. Seems that's what happened! (my 32sii is 1/2" thick). regards, Bill

 Re: HP33SMessage #5 Posted by Nelson M. Sicuro (Brazil) on 22 Aug 2003, 10:16 p.m.,in response to message #4 by bill platt Ops!!! My mistake. Just messed up in the conversion mm <> cm... What a shame! And I'm surrounded with calculadors..... Best regards Nelson

 Re: HP33SMessage #6 Posted by Torsten Hartwig (Germany) on 23 Aug 2003, 1:15 a.m.,in response to message #5 by Nelson M. Sicuro (Brazil) 1 inch = 25.4 mm But when you take the dimensions of the HP-33S you get 158.0 mm / 6.2 inch = 25.48387097 83.0 mm / 3.2 inch = 25.9375 16.1 mm / 0.06 inch = 268.3333333 Best regards, Torsten Edited: 23 Aug 2003, 1:38 a.m.

 Round-off errorMessage #7 Posted by bill platt on 23 Aug 2003, 1:23 p.m.,in response to message #6 by Torsten Hartwig (Germany) Hello Torsten, Let's 1st assume that the device was "designed" in metric. So, 158/25.4=6.2204.....round to 6.2 ok but: 83.0/25.4=3.267717.....so should round to 3.3. So, this one is goofy. The 16.1 case is obvious in the decimal slip (hmmmm-maybe the text writer used a slide rule!!!!!) But this all brings up an interesting point: If you want to design something that has an exact conversion to exact (non-repeating decimal) in another unit system, you have to bear in mind the conversion. So, if you design in inches, and you make all your dimensions rational and non-repeating, then all the dimensions will scale to perfectly clean millimeter (centimeter, meter) dimensions. But it does not work in reverse--and that is part of the wonder, beauty and mystery of numbers: All finite place decimals, when multiplied by a finite decimal place factor, produce finite decimal place products. BUT A finite decimal place number, when divided by a finite decimal place number may or may not produce a repeating or infinitely long decimal dividend. So, the real result is that ALL good designs should be carried out in INCHES, or FEET (1 meter = 0.3048 feet exactly) ;^} Example, a standard "NATO" round is known now as a "7.62" but what it really is is 30 caliber (3/10 inch). But 9mm does not convert cleanly..... So much for metric.....! Edited: 23 Aug 2003, 1:27 p.m.

 Re: Round-off errorMessage #8 Posted by Torsten Hartwig (Germany) on 23 Aug 2003, 6:28 p.m.,in response to message #7 by bill platt Hello Bill, When I posted my last message I felt an uneasiness with the numbers (in cm and inch) describing the dimensions of the calculator. But I did not really know what it was. While reading your posting I had this idea: The number of decimal places do not correspond. Example: When you enlarge the length of the calculator (6.2 inch) for the smallest amount representable (0.1 inch) you get 25 (rounded) units of the last decimal place of the metric number: 6.2 inch * 25.4 = 157.5 mm (rounded) 6.3 inch * 25.4 = 160.0 mm (rounded) But when you do it the other way round, the last decimal place is unchanged: 158.0 mm / 25.4 = 6.2 inch (rounded) 158.1 mm / 25.4 = 6.2 inch (rounded) So, my suggestion for HP is to have two instead of only one decimal places to represent the number of inches. BTW a minor correction to your posting (1 meter = 0.3048 feet): It should be 1 feet = 0.3048 meter as 12 * 2.54 cm = 30.48 cm. Best regards, Torsten

 Re: Round-off errorMessage #9 Posted by r. d. bärtschiger. on 23 Aug 2003, 7:34 p.m.,in response to message #7 by bill platt But don't forget, there is both land diameter & groove diameter when refering to calibers and bullets. 7.62 NATO is the land dia. = 0.30000". The groove dia is 0.3080" same as .30-06 Govt. or .308 Win. for example. The actual bullet dia. is 0.3080" or 7.8232m.m. As to the 9mm, I'm not sure what your point is. Also the word 'caliber' has two different meanings depending on use. That is 30 caliber is not the same as caliber 30. For instance the 'M1 Garand' is a 'United States Rifle Caliber 30 Model M1' and uses a .30-06 cartridge. 30 caliber on the other hand means the barrel length is 30 times the diameter of the projectile. This is used mainly for large sized Naval guns. See the following: http://www.chinfo.navy.mil/navpalib/ships/battleships/missouri/mo-may86.jpg This shows photo of a gun turret of the Missouri, with a caption which alludes to this meaning. and this: http://www.britannica.com/eb/article?eu=18955&tocid=0&query=caliber&ct= Which gives the various definitions of caliber. rdb. Edited: 23 Aug 2003, 7:47 p.m.

 Re: Round-off errorMessage #10 Posted by Frank B. (Germany) on 24 Aug 2003, 11:27 a.m.,in response to message #9 by r. d. bärtschiger. Hi, I might be wrong but I think the bridge mentionend on the first photo is _not_ the Golden Gate Bridge, but the Bay Bridge. Frank.

 Re: Round-off errorMessage #11 Posted by r. d. bärtschiger. on 24 Aug 2003, 1:14 p.m.,in response to message #10 by Frank B. (Germany) Yes, it is the bay bridge. rdb.

 Re: Round-off errorMessage #12 Posted by Nelson M. Sicuro (Brazil) on 23 Aug 2003, 8:36 p.m.,in response to message #7 by bill platt Why do the world isn't yet using just one unit system? I think that new designs should use the international metric system. Here we allways used metric (decimal) unit systems and we hadn't no problem of this kind as I remember. The problem is when we have some product that is in inches or feet or miles or (name it), and need to do several conversions. Just my 2 cents (or R\$0,05?)... Regards, Nelson

 Re: Round-off error (Long)Message #14 Posted by Nelson M. Sicuro (Brazil) on 24 Aug 2003, 9:00 p.m.,in response to message #13 by bill platt Well, I'm not an engineer, I'm a computer analyst/programmer and I doesn't have any fancy experience in such proportions. I just think that new designs have to take in account the other countries as well (unless it is only a local product). Yes, the metric system is easy, and it is used in all distance measuring using only decimal multiples, from sub-atomic proportions to interplanetary distances. I know that the north-americans doesn't like much the french and the metric was create by them, but it was accepted as an universal system. It is a question of accepting the ideas from others, not only your own (as an example: Santos Dumont [brazilian] having the first airplane to fly with its own propulsion, in Paris [France]). Excuse my ranting, I'm just tired of see north-americans (not all, of course) thinking that they are the Center of the Universe and just ignoring the rest of the world, or paying attention to the other countries having in mind only selfish interests. Please don't take it personally. I don't have anything against the american people (as a people) as I don't have anything against any other people. I'm an american too, but from the south half of the America. Here in Brazil we are a much more "blended" people, with persons that came from different cultures from all five continents. I just think that the world is bigger than only one nation. Ok, i'm way off topic... Let's talk again about HP calculators! Yes, they are a great north-american design and I use a HP-42S in a daily basis (before was a HP-15C), and I really feel sorry when HP took it both off production line. I just hope that the HP-33S fill the gap despite its ugly keyboard. Best regards Nelson

 Re: Round-off error (Long)Message #15 Posted by Ellis Easley on 26 Aug 2003, 4:46 a.m.,in response to message #14 by Nelson M. Sicuro (Brazil) Don't say "north American" when you mean the US - Canada and Mexico are metric, and they don't like being lumped in with US!

 Re: Round-off errorMessage #16 Posted by unspellable on 25 Aug 2003, 4:28 p.m.,in response to message #7 by bill platt Example, a standard "NATO" round is known now as a "7.62" but what it really is is 30 caliber (3/10 inch). But 9mm does not convert cleanly..... You don't get off that easy. The Nato 7.62 mm bullet is 0.308" in diamter and in its civilian guise is known as the 308 Winchester...

 Re: RoundsMessage #17 Posted by bill platt on 26 Aug 2003, 4:19 p.m.,in response to message #16 by unspellable Unspellable et al, Well, you are right-----my general ingorance (a little learning is a dangerous thing) on this topic has been exposed. Now, how about a real off-topic issue: I have heard it said that the Soviets had their own caliber, which was slightly larger than the 7.62, and that the purpose of this difference was so that the soviet rifles could use 7.62 rounds, but the other side would be unable to use the soviet rounds. Is this true?

 Re: RoundsMessage #18 Posted by r. d. bärtschiger. on 26 Aug 2003, 4:39 p.m.,in response to message #17 by bill platt Basically, yes. I will try to find a reference if you would like to see more information about this. rdb.

 Re: RoundsMessage #19 Posted by r. d. bärtschiger. on 26 Aug 2003, 5:11 p.m.,in response to message #17 by bill platt This may be what you are looking for. http://www.bertsoer.nl/sniper/sniperrifls/SV-98i.htm 7.62x54mm r russian. 7.62x51mm nato. The length of the 7.62 nato is 51mm from head to shoulder, whereas the russian is 54mm. Thus the russian round is 3mm longer and thus it would not fit the chamber of a 7.62 nato firearm. Also the 'r' may mean that it is rimmed, whereas the nato is rimless. rdb. Edited: 26 Aug 2003, 9:36 p.m.

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