Diagnosis of Malfunctions in Complex Electronic Assemblies. Final Report. Page: 46 of 66
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The tantalum capacitor that was reversed was not rejected by either tester
until the voltage had been applied for several minutes. Verifier test time
was shorter than inspection test time, causing the fault to go undetected.
The tester could detect pulse width differences within 70 nanoseconds
throughout a range of 500 nanoseconds to over 10 milliseconds by adjusting
the pulse width detector. The logic-1 levels could be verified to within
Passive-Component Detector Evaluation. This circuitry was mostly open
setup, and was evaluated to determine the accuracy of measurement and
the percentage of passive components that could not be evaluated because of
parallel circuitry or inaccessible circuit nodes. The following results were
" Over 96 percent of the components could be evaluated by two-stage
i The accuracy was within 5 percent for inductors and capacitors, and
1 percent for resistors over ranges of 10 ohms to 10 megohms, 5 pF to
10 uF, and 100uH to l0H.
Production-Line Tester Evaluation. The Verification2 Tester was evaluated
on the production line, with the following results.
"" The assemblers working with the tester maintained a good attitude toward
operating the tester and the results assured them that they had fabricated
the assembly correctly.
' The bargaining unit, agreed that the production assembler should operate
the tester, but only to isolate fabrication errors. Final rejection of a
bad component was to be treated as work falling in the troubleshooter
Cost of a Typical Tester. The tester design was oriented toward operating
simplicity, low cost, and small size. Development cost for material, build,
and design was estimated at approximately $6, 000. Inspection tester costs
for the assembly were eight to ten times the verifier cost because of the
inspection requirements for measurement accuracies of output parame-
ters. The development cost was higher than the cost of a similar production
tester because of the extra cost of experimentation required in development.
The cost of sophistication and automation should be justified by the economic
gains they yield from reducing the task rate.
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Losure, J. A. Diagnosis of Malfunctions in Complex Electronic Assemblies. Final Report., report, January 1, 1971; Kansas City, Missouri. (https://digital.library.unt.edu/ark:/67531/metadc1031893/m1/46/: accessed March 20, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.