The Museum of HP Calculators

HP Forum Archive 18

 Changing the positioning of the arithmetic keys -- why?Message #1 Posted by Palmer O. Hanson, Jr. on 31 Dec 2007, 11:13 p.m. The great majority of HP handheld machines from the HP-35 through the HP-41 have the arithmetical operations keys to the left of the numerical keyboard and reading the operations keys from the bottom upward the sequence is / x + -. The exception that I am aware of is the HP-10. HP machines after the HP-41 have the arithmetical operations keys to the right of the numerical keyboard and the sequence from the bottom upward is - + x / . The changed layout made the layout on the HP machines similar to that on machines made by TI, Sharp, Unisonic and many other manufacturers. Back in the HP-35 days the desktops such as the HP-91 and HP-97 had the TI/Sharp/Unisonic et al style layout. I have to presume that there was some reasoning behind all of that. There is no mention of this in Wlodek's book. Does anyone know why?

 Re: Changing the positioning of the arithmetic keys -- why?Message #2 Posted by Karl Schneider on 31 Dec 2007, 11:53 p.m.,in response to message #1 by Palmer O. Hanson, Jr. Hi, Palmer -- I recall having opined on that. Here's an excerpt from a post of mine on 25 March 2007 (Archive 17), buried deep in a thread that you started ("Cash for your trash?"): Quote: The columns of arithmetic keys of pre-Voyager and Voyager HP's are arranged as shown: pre-Voyager Voyager (leftmost) (rightmost) - / + * * - / + What's wrong with the pre-Voyager arrangement? The fingers of the user's right hand conceal the number keys when an arithmetic key is pressed. (90% of people are right-handed, and would use that hand to press keys.) The corresponding members of the functional pairs (-, +) and (*, /) are oriented inconsistently (i.e., - above +, but * above /) Starting with the Voyager series, HP "wised up" and arranged their arithmetic keys the way TI had done it since the 1970's. For more detail, though, there was a nice long thread on this very topic a few months ago: -- KS Edited: 1 Jan 2008, 2:05 a.m.

 Re: Changing the positioning of the arithmetic keys -- why?Message #3 Posted by Palmer O. Hanson, Jr. on 1 Jan 2008, 9:50 p.m.,in response to message #2 by Karl Schneider You wrote Quote: For more detail, though, there was a nice long thread on this very topic a few months ago: Thank you for locating the long thread. I can't understand how I missed it since I have been intrigued by the change in keyboard design ever since I stumbled on it some time ago when I was using a 41 and a 28 side-by-side for some comparative calculations. Somewhere in the long thread you wrote Quote: ... My view is that HP reconsidered the design, deciding that the arrangement used by TI perhaps made more sense for most users and adopted it -- not specifically to be consistent with TI, which, needless to say, would be clearly unimportant. It seems to me that at the time the switch was made it would have been quite important to the HP community to not make a change which made the HP machines look more like the TI machines.

 Re: Changing the positioning of the arithmetic keys -- why?Message #4 Posted by Trent Moseley on 1 Jan 2008, 10:39 p.m.,in response to message #3 by Palmer O. Hanson, Jr. All this leads to the question of why the telephone keypad is reversed from the calclator keypad i.e., from top to bottom? I think the Bell System had their design out first. (I'm just an old retiree). tm

 Re: Changing the positioning of the arithmetic keys -- why?Message #5 Posted by Karl Schneider on 2 Jan 2008, 1:57 a.m.,in response to message #4 by Trent Moseley Quote: All this leads to the question of why the telephone keypad is reversed from the calculator keypad i.e., from top to bottom? I think the Bell System had their design out first. Trent -- I'm sure that you recall (as even I can), that the ten digits on the rotary dial were arranged sequentially counterclockwise as 1 through 9, then 0. Dialing a given digit generated a corresponding series of pulses, with "0" giving ten pulses. The successor touch-tone keypad compactly arranged the rotary-dial digits as the lines of a Western language would be written -- left-to-right, proceeding from top to bottom. Complete telephone numbers are merely codes -- a sequence of digits. In the US (and perhaps most countries), "0" by itself also served a special purpose to reach the Operator. Conversely, on the input to a computing device -- such as a ten-key or a calculator keypad -- the digits have quantitative values. So, it makes more sense to physically arrange the digits by magnitude in a consistent and intuitive order: increasing bottom-to-top, then left-to-right. -- KS Edited: 2 Jan 2008, 3:19 a.m.

 Re: Changing the positioning of the arithmetic keys -- why?Message #6 Posted by Walter B on 2 Jan 2008, 4:36 p.m.,in response to message #5 by Karl Schneider Quote: In the US (and perhaps most countries), "0" by itself also served a special purpose to reach the Operator. FWIW, the USA is the only country I know right now having such an operator service. Elsewhere you are supposed to be able to operate a phone on your own. AFAIK, many countries use a leading zero to call "out of town" and two leading zeros to call a number in another country. In analogy, in many companies (and hotels) a single zero gets you the external line. Edited: 2 Jan 2008, 4:40 p.m.

 Landline telephone serviceMessage #7 Posted by Karl Schneider on 2 Jan 2008, 10:54 p.m.,in response to message #6 by Walter B Quote: FWIW, the USA is the only country I know right now having such an operator service. Elsewhere you are supposed to be able to operate a phone on your own. Well, we're not required to use the operator, but it's nice to have the services available. We've had direct long-distance dialing since 1951, although universal availability certainly came later. Quote: AFAIK, many countries use a leading zero to call "out of town" and two leading zeros to call a number in another country. That's how it was in Germany 20 years ago, so that hasn't changed. Back then, though -- as I'm sure you remember -- the government-owned Deutsche Bundespost (post office) ran the telephone system. This probably explained why my pushbutton phone generated pulses instead of tones, and why the cord was hard-wired into the wall, instead of connected via a modular jack. I was appalled! DBP also introduced their toll-free service in early 1989 ("Ortstarif"), 22 years after it debuted in the US. I expect that the privatized Deutsche Telekom has modernized things. Quote: In analogy, in many companies (and hotels) a single zero gets you the external line. "9" generally serves that purpose in the US. -- KS Edited: 3 Jan 2008, 2:13 a.m.

 OT: Re: Landline telephone serviceMessage #8 Posted by Walter B on 3 Jan 2008, 6:21 p.m.,in response to message #7 by Karl Schneider Quote: Well, we're not required to use the operator, ... I didn't claim you have to :) Quote: DBP also introduced their toll-free service in early 1989 ("Ortstarif") ... IIRC the "Ortstarif" (tariff for local calls) is far older, but it was never toll-free. What's true is the DBP was a real public agency ("Behörde"), and you can still feel the heritage when dealing with the Telekom. Privatization has brought competition, however, bringing the prices down so far. "Phone culture" has changed completely in 20 years. Yes, also we have modular jacks for quite some time now, allowing us to build our own net at home - and relying almost fully on our own if we made errors ;) After all, these are topics for another forum.

 Re: Changing the positioning of the arithmetic keys -- why?Message #9 Posted by Hal Bitton in Boise on 2 Jan 2008, 12:29 a.m.,in response to message #2 by Karl Schneider My (unique?) opinion on this subject... I liked the original early key arrangement, because it grouped the arithmatic keys nicely under the enter key. For a right handed user, this was nice because one didn't have to withdraw the right hand from the keyboard to get at the enter / operations keys. IMO, obscuring the number keys is not really an issue if one knows 10 key. One of my biggest gripes about the 49/50 series is the banishment of the enter key to the obscurity of the extreme lower right corner. On an RPL/graphing machine, the enter key is too critical to be so exiled. They may as well have put it on the back of the calculator. Best regards, Hal

 Re: Changing the positioning of the arithmetic keys -- why?Message #10 Posted by Thomas Radtke on 2 Jan 2008, 4:49 a.m.,in response to message #9 by Hal Bitton in Boise Using two classics lately, the 35 and the 45, I found that I prefer the old arrangement: I know where each of the numeric keys is but I can't remember the arrangement of the binary operators. It follows that shadowing these operator keys are much more of a problem than finding the number blindly. There's more to it: Pressing the wrong numeric key ist immediately obvious in the display. Using the wrong operator is not.

 Re: Changing the positioning of the arithmetic keys -- why?Message #11 Posted by Dave Shaffer (Arizona) on 2 Jan 2008, 1:50 p.m.,in response to message #10 by Thomas Radtke I agree with Hal and Thomas - I, too, much prefer the older '35 arrangement. I want to see which function I need to push and am not too concerned about which number to hit.

 Re: Changing the positioning of the arithmetic keys -- why?Message #12 Posted by Walter B on 2 Jan 2008, 4:50 p.m.,in response to message #11 by Dave Shaffer (Arizona) Binary operators to the left or right do not make a big difference for me. However I find the new sequence of operations (i.e. + - x / from bottom up) far more logical than the old ( / x + - ), though I started with a Woodstock.

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