EARLY TRANSISTOR
HISTORY AT IBM
Hannon S. Yourke
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Oral History – (Continued) |
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The top photo shows various transistors manufactured by IBM in the
1950s and illustrative of the types of transistors available to Hannon Yourke
for his circuit development work. The
unit on the left is a type 51 NPN alloy junction germanium transistor used in
trigger circuits on the IBM 608 Transistor Calculator. This particular
transistor is still functional and the date code (276) indicates that the
transistor was manufactured during week 27, 1956. The unit on the right is a type 013, manufactured in 1958, week
20. It is a PNP alloy junction
germanium type, developed for current switching applications. The unit in the
center is an experimental hand labeled type. The photo on the left is a section of a 1955 magazine ad from IBM,
with accompanying text outlining the virtues of transistors for electronic
computer use. Although not
identified, the machine is likely the 608 Transistor Calculator. Each of the
printed circuit cards held multiple transistors in sockets, as shown in the
card held by the hand. The 608 used more than
2000 transistors.
Go
To Yourke Oral History, Page 4 |
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COPYRIGHT
© 2004 by Jack Ward. All Rights
Reserved. http://www.transistormuseum.com/ PAGE
3 |
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