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HP 9100A/B Transistors

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HP 9100A/B Transistors
Richard Wilder Offline
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#1
11-05-2011, 11:12 AM

Anyone know the significance of the colored paint dabs on many of the transistors in these calculators? Maybe they were hand selected for parameters to work in the particular circuit(?)

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Joel Setton (France) Offline
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#2
11-11-2011, 09:08 AM

Richard,


The HP Journal article on the 9100 mentioned that the transistors were burned-in, to detect early failures and improve reliability. As far as I know, this is not related to select a particular parameter.


I hope this helps!


Joel

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