On Sun, 19 Aug 2018 09:56:08 -0700, John Larkin
wrote:

The engineering approach to fixing things is to probe
around, understand how it's supposed to work, and figure out why it
doesn't.

Nope.

The difference between engineering and repair is that the engineer
assumes that the problem is due to a design error and fixes the
problem by redesigning the circuit. The repair tech assumes that it
was designed and built correctly, therefore something has blown.

The engineers needs to make production lots of an instrument work. The
repair technician usually needs to make one work.

The engineer tries to determine how the circuit should work. The
repair tech tries to determine what the engineer was thinking when he
designed the circuit.

The engineer understands how the circuit should work. The technician
understands what the circuit actually does.

The engineer has experience making the instrument work under
laboratory conditions. The technician has experience making it work
in the rather nasty "real world" environment.

The engineer selects components based on availability, performance,
price, and lifetime. The repair tech substitutes whatever can be
found in his junk box.

The engineer writes the documentation partly to demonstrate to the
world the cleverness and greatness of his design. The repair tech
doesn't read the documentation unless he's desperate.

The engineer makes measurements in order to find problems. The repair
tech looks for smoke, burned parts, bulging capacitors, broken
connections, manufacturing errors, and mechanical damage. Well, maybe
he does take a few measurements like the power supply voltages.

All this works very nicely as long as engineers don't try to act like
technicians and technicians don't try to act like engineers.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558