169:
replacement of the batteries). As the lid edges were made of a harder metal, the plastic notches in the case were prone to cracking or breaking, even in carefully kept devices. Surviving examples of the earlier versions of this calculator frequently have rubber bands around or tape over the cover to hold it in place (including the image attached to this article). This defect was later remedied on the HP-19BII, by putting the battery cover underneath the chassis.
115:. However, by 1988 that capability had become so common on calculators that it was no longer a feature of distinction, as it was an assumed characteristic of all serious scientific and business calculators. So beginning with the HP-28S, HP-17B, HP-19B, and HP-27S, the feature suffix "C" was replaced with a class suffix which was more meaningful in the market: "S" for Scientific, "B" for Business, and later (in 1993) "G" for Graphic.
33:
168:
batteries made a considerably strong force, and the notches on the case in which the lid edges slid were too thin and shallow. Even if the case itself was sturdy enough, those notches were under extreme pressure, most especially while the user was opening or closing the lid (such as during the
128:
The HP-28 calculators shared a flip-open ("clamshell") case. On the left side of the flip, there is an alphabetic keyboard (in alphabetic order). On the right was a typical scientific keyboard layout.
152:
Among the drawbacks of the HP-28 was the lack of a computer interface. This meant that stored information could only be entered through the keypad and not backed up.
88:. A year later, the more common HP-28S was released with 32 KB of RAM and a directory system for filing variables, functions, and programs. The HP-28C used a
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that used the same clamshell design and internals) had one design problem that affected many units: the springs inside the unit that made contact with its three
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The HP-28C was the last HP model introduced with the suffix "C" in its model designation – a practice which HP had started with the
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from 1986 to 1992. The HP-28C was the first handheld calculator capable of solving equations
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whereas the HP-28S used a custom chip containing an improved Saturn processor core codenamed
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353:, Portable Computer Division. October 1986. HP reorder number 82240-90001 (82240-90008).
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RPN 28x Calc -- A scientific calculator with a nostalgic, HP-28S-like interface for iPad
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Wickes, William C. (January–February 1987). "The HP-28C: An
Insider's Perspective".
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pictures on MyCalcDB (database about 1970s and 1980s pocket calculators)
393:(in French) (2 ed.). Paris, France: Editions de la Règle à Calcul.
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programming language interface first introduced in these HP-28 series.
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back in 1976. The "C" had distinguished those models as having
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Two models were produced, the HP-28C came first in 1987 with 2
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HP-28 Insights: Principles and
Programming of the HP-28C/S
27:
Series of graphing calculators produced by
Hewlett-Packard
312:
HP-28S Advanced
Scientific Calculator Reference Manual
281:
HP-28S Advanced
Scientific Calculator Owner's Manual
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64:of calculators, which grew from the menu-driven
84:, and was the first handheld calculator with a
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379:. August 1989. HP reorder number 82240-90014.
8:
184:Halcyon Calc for iPhone, iPod Touch and iPad
513:
499:
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433:. Corvallis, Oregon: Larken Publications.
237:Hewlett-Packard Development Company, L.P.
31:
223:
201:Comparison of HP graphing calculators
7:
387:; Lalande, SĂ©bastien (2006-06-27) .
233:"Hewlett-Packard Calculator Firsts"
375:(1 ed.). Corvallis, OR, USA:
349:(2 ed.). Corvallis, OR, USA:
322:. November 1988 . HP 00028-90068.
291:. November 1988 . HP 00028-90066.
25:
470:HP-28 at the HP Calculator Museum
523:Hewlett-Packard (HP) calculators
405:from the original on 2016-08-06
360:from the original on 2016-08-06
329:from the original on 2015-06-08
298:from the original on 2015-06-08
390:Voyage au centre de la HP28c/s
92:processor running at 640
1:
60:. They were replaced by the
1208:Products introduced in 1986
827:Scientific non-programmable
549:
544:
429:Wickes, William C. (1988).
231:Nelson, Richard J. (2010).
1224:
373:HP 82240B Infrared Printer
343:HP 82240A Infrared Printer
148:Lack of computer interface
137:The display was a 137Ă—32
649:Scientific programmable
211:HP 82240A character set
86:Computer Algebra System
938:Financial and business
100:and running at 1
37:
213:(Modified HP Roman-8)
35:
1198:Graphing calculators
486:The HP28 WWW Archive
160:This model (and the
50:graphing calculators
206:Graphing calculator
1170:Emulation software
156:Weak battery cover
38:
1185:
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113:continuous memory
62:HP 48 series
16:(Redirected from
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318:(4 ed.).
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243:on 2010-07-03.
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450:HPX Exchange
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407:. Retrieved
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362:. Retrieved
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331:. Retrieved
311:
300:. Retrieved
280:
259:. Retrieved
249:
241:the original
226:
162:HP-19 series
159:
151:
136:
127:
106:
75:
58:symbolically
52:produced by
45:
41:
39:
29:
133:LCD display
1192:Categories
1115:OfficeCalc
409:2015-09-06
364:2016-08-06
333:2015-10-10
302:2016-08-07
261:2015-09-13
218:References
142:dot matrix
80:of usable
1120:PrintCalc
1105:QuickCalc
399:636072913
173:Emulators
124:Clamshell
78:kilobytes
48:were two
1110:EasyCalc
970:Prestige
965:Platinum
839:6s Solar
532:Graphing
403:Archived
355:Archived
324:Archived
293:Archived
190:See also
1088:CalcPad
640:Xpander
255:"HP28S"
166:N-sized
72:History
992:17bII+
955:10bII+
475:HP-28S
437:
397:
119:Design
109:HP-25C
90:Saturn
46:HP-28S
42:HP-28C
36:HP-28S
18:HP-28S
1151:FOCAL
1071:Other
1007:19BII
987:17BII
950:10bII
929:300s+
864:10sII
813:9100B
808:9100A
723:32SII
635:Prime
615:48gII
575:39gII
358:(PDF)
347:(PDF)
327:(PDF)
316:(PDF)
296:(PDF)
285:(PDF)
98:Lewis
924:300s
859:10s+
818:9805
763:41CX
758:41CV
625:49g+
610:48GX
605:48G+
595:48SX
585:40gs
570:39gs
565:39g+
456:(1).
435:ISBN
395:OCLC
44:and
40:The
1177:16C
1161:CAS
1156:ALG
1146:PPL
1141:RPL
1136:RPN
1098:200
1093:100
1042:38E
1037:38C
1032:37E
1027:30b
1012:20b
1002:19B
997:18C
982:17B
977:14B
960:12C
945:10B
899:32E
894:31E
889:30s
884:27S
874:22S
854:10s
803:97S
793:95C
788:71B
768:42S
753:41C
748:35s
743:34C
738:33s
733:33E
728:33C
718:32S
713:29C
708:25C
698:21S
693:20S
688:19C
683:16C
666:15C
661:11C
656:10C
630:50g
620:49G
600:48G
590:48S
580:40G
560:39G
555:38G
550:28S
545:28C
139:LCD
102:MHz
94:kHz
82:RAM
66:RPL
1194::
1083:10
1078:01
1062:92
1057:81
1052:80
1047:70
1022:27
1017:22
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909:45
904:35
879:27
869:21
849:9s
844:8s
834:6s
798:97
783:67
778:65
773:55
703:25
676:CE
671:LE
540:9g
452:.
401:.
235:.
104:.
514:e
507:t
500:v
454:1
443:.
412:.
367:.
336:.
305:.
264:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
