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1<?php
2        $seiten_id = 'personalcomputer';
3        $version = '$Id$';
4        $titel = 'Historical Personal Computers: The first PCs';
5       
6        require "../../lib/technikum29.php";
7?>
8   <header class="teaser seitenstart">
9        <img src="/shared/photos/rechnertechnik/header-wang2200.jpg" width="940"  height="545">
10        <h2>Historical Personal Computers</h2>
11</header>
12
13<h3 id="wang2200"><b>WANG 2200B</b> with an extensive set of peripherals</h3>
14
15<p>An often posed question is that of how to define the notion of a "personal
16computer". We would answer like this: "A personal computer is a single-user
17system with attached display (back then typically a CRT) and a suitable
18complement of peripherals to store and retrieve data and for input/output of
19data and programs. It is also easily transportable."<br>
20
21One of the first personal computers, PC for short, is the WANG 2200 A/B dating
22back to 1973. Wang realized pretty early that a key component for such a device
23was an electronic display capable of displaying multiple lines at once.
24Comparable HP systems from that time only had a single line LED-display. A nice
25comparison between these two types of machines can be found here:
26<a href="http://www.wang2200.org/docs/internal/HP_Competitive_Analysis_9830_vs_Wang_2200B_Mar_1974.pdf" target="_blank"> HP competitive Analysis 9830 vs WANG 2200B (PDF)</a>.
27<br> 
28This is, in fact, a comparison performed by HP and was suited to aid the
29salesperson when he or she faced a situation where HP had to compete agains a
30Wang offer. HP and WANG were THE opponents in these days when it came to
31scientific calculators and early PCs.  <br>
32        The system 2200 and its successors featured a plethora of peripheral devices as
33well as a vast library of programs for a variety of scientific and commercial
34problems. Though, there was no assembler or access to machine language at all.
35The system was programmed in a BASIC dialect.<br>
36       
37  The system on display here is unique in Germany with its set of peripheral
38devices: Paper tape reader (2203), card reader (2234), marker card reader
39(2214), triple 8 inch diskette drive (2270-3) and a disk subsystem (2230-1)
40with 14 inch disks. The weight of the disk subsystem alone is about 100 kg, and
41it cost a whopping 24 000 DM back in its days. Its total capacity is 5 MB for
42programs and data.</p>
43       
44        <h3 id="wang2200s"><b>WANG 2200S</b></h3>
45       
46        <div class="box center">
47        <img src="/shared/photos/rechnertechnik/wang-2200s.jpg" width="350"  height="304" />
48        <img src="/shared/photos/rechnertechnik/wang-2200s-detail.jpg" width="429"  height="304" />
49        </div>
50       
51        <p>This new acquisition (December 2017) is a smaller version of the WANG 2200B,
52built in 1974/75, the "S" probably denoting "small". The additional magnetic
53tape unit (2217) allows to store 1.7 kB of data on one meter of tape at a
54transfer rate of 326 characters/second. It is equipped with three independent
55motors and capable of reading/writing in both directions. The tape is always
56written/read in blocks of 256 bytes. As slow as it is, the low price of the
57storage media more than compensated for that. <br>
58
59Also interesting is the golf-ball typewriter as output device. Thanks to the
60unique stepper motor driven mechanics, the system can also be used to plot
61graphs.  The model 2202 is identical with the model 702 typically used in
62conjunction with a <a class="go" href="/en/computer/ic-technology.php#WANG_700" target="_blank">WANG 700 system.</a> </p>
63
64         <p class="small">We would like to express our thanks to the University of Muenster who donated this system.</p>
65         
66         
67         <h3 id="wang-pcs"><b>WANG PCS II</b></h3><br>
68       
69        1977 WANG introduced the new computer PCS-II, a much more compact system than
70the 2200-series. The central processor was still implemented with discrete TTL
71ICs and shared a common enclosure with all necessary interface connectors and
72the power supply. A dual 5.25" diskette drive was attached at the top, so the
73only other peripheral device was a printer. Memory could be expanded up to 32
74kB, as small as the memory featured by the much cheaper PET made by Commodore.
75
76        <div class="box left">
77        <img src="/shared/photos/rechnertechnik/wang-pcs-2.jpg" width="241"  height="202"/>
78        <img src="/shared/photos/rechnertechnik/wang-pcs-2-innen.jpg" width="268"  height="202"/>
79        </div>
80       
81        The picture shows the implementation of the machine. All in all, four printed
82circuit boards (PCBs for short) crammed with ICs, were required. Repairing a
83machine like this can easily turn out to be a veritable nightmare.
84        <br>
85        The machine was much too expensive for private citizens: In 1978, one would
86have had to pay 20 000 DM ($ 7500) for a machine like this. A reasonable car like a
87FORD Capri Sportcoupe would have cost only 12 000 DM in comparison!
88        <br>
89       
90        <p class="bildtext small">This beautifully preserved machine is currently not functional. We would trade
91it for another, equally valuable system suitable for our museum. If you are
92interested, please do not hesitate to contact us.</p>
93       
94       
95         
96         <h3 id="cbm"><b>Commodore (CBM) PET 2001, 8096-SK</b></h3><br>
97         
98        The Commodore computers are popular amongst the vintage computing community and thus not too interesting for our exhibition.
99        Anyway, for completeness, we have some devices in our collection.
100       
101        <br>
102         
103        In 1977, most pupils already heard about the new computer technology and wanted to gain experience.
104       
105          <div class="box left">
106        <img src="/shared/photos/rechnertechnik/ur-pet.jpg" width="300"  height="266" />
107        </div>
108         <div class="box right">
109        <img src="/shared/photos/rechnertechnik/pet+floppy.jpg" width="500"  height="266" style="margin-top:1em" />
110        </div>
111       
112        <p>
113        The PET 2001 is a 2000 DM (~1000 US $) device by Commodore and thus was also affordable by schools. Virtually overnight
114        computer pool rooms were created where one had to sign up in a waiting list in order to get entry -- or to wait up to
115        late in the evenings (after 6pm) to enter.
116       
117        <p>In the beginning, the PET offered 7kB RAM and the very slow "datasette". This long term storage medium was nothing
118        more than a standard 1970s compact cassette recorder. The PET was programmed in BASIC.
119        <br>Soon it was obvious that this general purpose computer was also suitable for games. In our
120        birthday workshops we observe that today's pupils are fascinated by these classical computer games
121        with their high level of abstraction and apparently no attempt to recreate reality.
122       
123        <p>The successor model replaced the miniature keyboard (actually quite suitable for children) by a regular one.
124        Given the money, it was possible to upgrade the machine with a 5,25" floppy disk drive which was as expensive as the
125        computer itself. However, with the disk drive it was possible to solve real world problems which made the computer
126        attractive for small buisnesses.
127         <div class="box left">
128        <img src="/shared/photos/rechnertechnik/commodore-8096.jpg" width="300"  height="276" />
129        </div>
130       
131        <p>In the subsequent models, the design was revised. Personal computers shall look elegant and beautiful, as demonstrated
132        by the 19080s model 8096-SK (also nicknamed "the egg"). 80 means 80 characters per row, 96 means 96 kB RAM and SK means
133        seperate keyboard -- the keyboard is removable. The monitor can be leant and rotated and can display big and small letters.
134        The workspace was completed with a dot matrix printer.
135        <br>Special software allowed to operate the computer without further knowledge.
136        <br>Some technical data:<br>
137       
138        Central processor: MOS 6502<br>
139        Processor frequency: 1 MHz<br>
140        RAM: 96 kByte,  ROM: 18 kByte<br>
141       
142       
143        <p>At this time, the mass production of personal computers started and our exhibition ends, since we concentrate on
144        rarities and very early computing in the 20th century.
145         
146       
147   
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