On 1/5/06, Mark Scoville <mscoville@unicontrolinc.com> wrote:
> So I guess the moral is "Don't overlook the easy stuff".
>

Here's a recent one.

I designed a board where an outside analog input could be connected to
the circuit in one of two ways.  To select this, I used a three-pin
header with a jumper to bridge two of the pins.

When assembly of the boards was finished, they worked fine except this
analog input was reading about zero voltage no matter what.  After
half an hour of troubleshooting, I remembered to install the jumper. 
Then the board worked.

So far this isn't a remarkable story.

But then I proceeded, for the next four or five of these boards I
deployed, to make the *exact same mistake*.  For each board I was
testing, I would notice the voltage was zero, then start to measure
the voltages down the circuit, then realize the jumper was missing.

Finally realizing how thick-headed I was, I decided to outsmart
myself.  I took each of the hundred boards out of their antistatic
bags, added the jumper, and put them back in the bag.  I haven't run
into the issue again.

Regards,
Mark
markrages@gmail
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