[Elecraft] mod wires vs. "professional appearance"
Ferguson, Kevin
[email protected]
Thu Nov 7 14:00:02 2002
Short version: to paraphrase Forrest Gump's mother, "Professional is
as professional does"
Long version:
I've designed, (my profession) and worked on hundereds if not
thousands of boards. (some designed by other professionals).
Enough that there is no way to guess how many.
Sometimes, on boards the size of a playing card, there will be no
mod wires. Often as not, though, there will still be one or two.
I can recall being involved with exactly ONE board that compared
with the K2's complexity, that did not have a single mod wire.
Everyone associated with that board was highly suspicious of the
fact.
EVERY other circuit of such complexety had at least one, and often
a dozen or more mod wires. Some of these are still flying in flight
critical roles on B-1bs, KC-10s, and yes, even on the Space Shuttles,
Yes, the ones NASA bought from Rockwell. There was, and I assume still
is (been away from that world for a while) a mil-specification on how
to correctly install mod-wires.
Mod wires are allowed in flight critical applications, because it is more
important that the circuit work as well as possible, than that it
"appear professional". If mod wires were frowned upon, there would be a
strong temptation to just "live with" sub-optimal performance...at least
that is the opinion of the professionals involved.
In digital circuits, the age of first PALs, FPGAs, etc. has greatly reduced
the number of mod wires, as mistakes can often be corrected in firmware.
Still have a few though. And the few programable devices available for
analog circuits haven't really cought on. Analog circuits will have lots
of mod wires. The K2 is mostly (except for control and display) an analog
circuit.
I once had a job working for a manager that thought mod wires were
unacceptable.
I found another job.
I once had an employee that was NASA certified for soldering. He could
explain in
great detail why each and every cold solder joint he made was to NASA spec.
After he was fired, he found another job......eventually.
Given that professionals use them (and how!) it seems very odd to hear that
mod
wires do not convey a "professional appearance" and that improving the
performance
of a circuit "ruins it".