An obvious fault

20-02-2007

Sometimes, when you are handed something to test, you can look at it and go "Yep, that wont work". You don't even have to install it to know it wont work. You don't need to follow any test procedures or run any confidence tests. You can just see an obvious fault that needs to be fixed first.

When asked to give a good example of a situation where this 'common sense' test technique has been applied before, I always remember my mate Steve from my college days. Long before I ever decided to pursue a career in computing I was studying to be an Electronics Engineer. On one particular day the Head of the college was showing some important guests around. All I can remember about these guests was that they were very important, possibly something to do with monetary investment in the college, so everyone had to be on their best behaviour. They came into our lab and we were all hard at work fiddling with our oscilloscopes, and soldering various components to PCBs we'd just etched. They wandered by each of our work stations looking at what we were doing until they finally arrived at my mate Steve's work station. Now Steve is a mature student as he liked to be called. He was 35 and we were all about 17. While we were busy working on our assigned projects, Steve had brought in the radio from out of his car and had it all opened up on his worktop. He was de-soldering a chip when the Head and his entourage walked up. Looking over his shoulder the Head decides to ask Steve a few questions.

"That looks interesting Steve. Could you tell us what you are doing there?"

"I'm removing this chip" replies Steve.

"Could you tell us what fault finding techniques you used to determine that it was that chip exactly that was at fault Steve?"

"Well, it has a bloody great big hole in it" replied Steve.