BL> At some stage, some tech has found the fault that led to the
 BL> "mod" sheet, so there is a fatal flaw in your logic.

 RG> OK, I tell a lie.... 'cos I have been responsible for
 RG> identifying (and modifying) at least 3 design flaws in various
 RG> machines, and my mods were taken up by the manufacturers.

  There'as a long sequence involved when this happens. First, a tech
in the boonies identifies the *actual* fault (and sometimes fixes it),
and then our techs try it and are convinced, then they call me in and
convince me (because they can't talk to Chinese engineers), and then I
write a series of FAXs that finally get the factory to *look* at the
problem, and only then do I give them the actual cure... which they
always change slightly to save face. Actually, the Chinese are better
than the Japs.

 BL> What you do, is develop a list of reliable techs who get it
 BL> right, and when they say they've found something "funny" you
 BL> check it out - quick!

 RG> Yeah right.... the scenario is more like, "there's no design
 RG> flaws in our machines - this is just an isolated case"

  Not really... if one of our "reliables" tells us he's got a live one
he's nearly always right.

  The problem from *our* point of view is that you have only seen one
or two sets, and if no one else is reporting the same fault, we either
have to wait and see what develops (an isolated case?), or lie to the
factory and hope *they* find it (or already know about it). The
problem with lying is that you lose credibility and they ignore you
the next time.

 RG> These days are long gone (for me) though... since branching out
 RG> on my own I don't seem to have the same 'respect' from
 RG> manufacturers that I used to have - should I find a design flaw
 RG> now I'm treated like any one of the other 1000's of "backyard
 RG> techs".

  The worst case is when there are lots of crook sets, no one knows
how to fix them, and half the techs in Australia have their own
opinion. Obviously, we have to stick to the "reliables" we know best.
  
 RG> 2. However weird or difficult the fault, it is never the
 RG> microprocessor.

  ROFL!

 BL> A tech will tip-toe away from something that is finally
 BL> working, and often never knows if he has found *the* fault.

 RG> Nope, I dissagree with you here... about the only time he's
 RG> never sure if he's found the fault or not is when they've had
 RG> to modify the circuit to get it going.

  There are many techs who "fiddle" a tough fault to avoid it rather 
than fix it, and some engineers do the same thing in design. To me, 
it's a matter of integrity.

 RG> Whether the fault has an underlying and intermittent cause is
 RG> another matter though.

  These are the ones it takes a real strength of character to run down
and find. Engineers do ite
 too. You know there is a fault... but it
only happens rarely. A good engineer will work on it until he
understands the *cause*. He may even choose to leave the fault, but he
should know why, and when.

 BL> What you call a "failed engineer" is just a fiddler, but there
 BL> are nevertheless true techs who have the true engineering
 BL> attitude, and vice versa.

 RG> Yup... There has to be a crossover point somewhere, but as you
 RG> say, it does take a different approach/mindset when designing
 RG> circuits than it does when faultfinding them.

  Yair. It's totally wrong to see a tech as a lesser-engineer, or an
engineer as a fiddling tech. They are different functions, and only
rare people can do both.

 BL> In the early days of transistor radios when I was fixing them
 BL> for money (at 6 an hour), I was the best tech in Sydney at
 BL> that. You suspend all thought and just *go* to the fault. You
 BL> "know" the set and hardly ever use a multimeter, let alone the
 BL> CRO an engineer can't live without.

 RG> Yeah... I know I've got a bitch of a fault when I need to get
 RG> out the MM ... and when I have to power up the CRO (about half
 RG> dozen times a year) the customer is looking at expensive
 RG> repairs.

  (grin) The CRO is a tech's last resort. And rightly! 

  And engineers aren't what they used to be, either. The last place I
worked, I was the only one who had the slightlest clue what it meant
to design for mass manufacture. Most of them were just trying to get
it working! OF COURSE it's got to work! The whole 100,000 have got to
work. And work the same, preferably...

Regards,
Bob



 

___ Blue Wave/QWK v2.12
@EOT:

---