Larry states it very well. HANDBOOK REQUIRED. If I were independently
wealthy I would offer the handbook free to anyone who made their living
designing PCBs. Imagine an industry where the interest was in quality,
knowledge, growth, and professionalism instead of short term profit. Wow.
-Ed
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message text
>I can see why people had so many problems with your Beta test. Select the
>most correct answer? My answer would be "B" for the following reasons.
>
>A. CAD systems do everything on a coordinated system, even if it's a
>submillimeter, it uses an X-Y coordinate. So yes, CAD systems require it,
>but this is not the BEST answer.
>B. Design standards do require it. Your IPC-D-275, para. 5.1.2 and the old
> MIL-STD-275, para. 4.3 require them. My feeling is that this is a
>carryover from before CAD came along (and yes, there are still people who
>use tape) and vendors needed to bombsight locations. Those locations
>usually were located on .025 centers. This was before surface mount came
>along. CAD has all locations located in electronic files, no matter what
>the dimension.
>C. It doe help the manufacturer, as long as it is a taped or manual layout,
> or they have no CAD data and must measure.
>D. Design standards do require measuring individual locations if they do
>not fall on a grid system. The grid system, again by spec, is a multiple
>of .005.
>
>So in essence, all the questions are correct to some extent, and none are
>technically wrong. To me this question is ambiguous, and I'm glad to see it
>was dropped. What I would hope to see in a test is something that would
>really show if you know your job, not to see if I could answer silly
>questions which are all correct.
>
>I am not trying to shoot down the certification process at all, I hope to
>take it in the future. I am definitely waiting for a study guide to become
>available before presenting my boss with a request to attend. I do hope the
>other questions will be more beneficial than this example. If I were to ask
>to attend the certification testing by showing my boss this first example, he
>would laugh me out of his office.
>
>I am looking forward to seeing other questions of the day. Hopefully, they
>will be helpfull in getting myself and my other co-workers certified.
>
>Sincerely,
>Larry Campbell
>Supervisor, P.W.B.
>BFGoodrich Avionics Systems,
>Jet Electronics & Technology, Inc.
>[log in to unmask]
>
>- - - - - - - - - - - - - - Original Message - - - - - - - - - - - - - -
>the following question is one that was provided by designers for the "A"
>basic level exam. It is NOT included in the final published test and is
>for reference only. The topic was Grid Systems.
>
>101. Why are grid systems used for locating components, PTH's
>conductor patterns and other features on printed boards and printed board
>assemblies?
>
> A. Because CAD systems require it.
> B. Because design standards require it.
> C. Because it helps in the manufacturing operations
> D. Because it avoids having to dimension individual
>locations.
>
> Select the most correct answer
>
> ********************************************************************
>
>Please send comments, constructive critique, or suggestions to Lisa
>Williams at [log in to unmask]
>
>Dieter Bergman
>
>
>
>- - - - - - - - - - - - End of Original Message - - - - - - - - - - - -
>
>
>
Edward K. Current [log in to unmask] *********************************
CAD Supervisor, Eng.Services Dept. * Ancient Irish Blessing *
Power Convertibles Corp. * Peace up to the heavens, *
3450 S. Broadmont Drive Suite.128 * the heavens down to the earth *
Tucson, Arizona 85713 * the earth beneath the skies *
Ph.# (520) 628-8292 ext.167 * strength to everyone. *
Fx.# (520) 770-9369 *********************************
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