 Mr.
Steve Gross has a nifty story from his time in the U.S. Navy as a shipboard
electronics technician in this edition of EDN's "Tales
from the Cube." When at sea, access to spare parts is very limited
so you often have to exercise a combination of ingenuity and creativity
(not necessarily mutually inclusive traits) to get the job done. In
his case it was the need to find a suitable replacement for a Darlington
pair transistor in a piece of specialized test equipment. With the help
of a visiting engineer, he came up with a working circuit.
 This
scenario reminds me of another of my own tales from earlier days as
a technician, but only from the standpoint of constructing a semiconductor
component from pieces of others. For a couple years I worked closely
with a few engineers on special projects. The guy who managed the small
group spent most of his career as a technician in the manufacturing
realm of the company. He was not a degreed engineer. His position was
secured because of a special relationship (yes, legitimate) with the
special customer. All the other team members (except me) were "real"
engineers, and they somewhat resented the manager's control over them
even though he never tried to "pull rank." One day the group was sitting
at a table discussing a particular circuit design and the manager made
a comment about making a transistor out of two discrete diodes. I kid
you not. You should have seen the looks the engineers (all electrical
types) gave each other when he said that. Even I, at the time working
on my BSEE degree at night, knew he had violated the old adage that
it is better to remain silent and appear to be a fool than to open your
mouth and remove all doubt. Yep, you guessed it. Because the schematic
symbol for a transistor - and the physical construction for that matter
- implies that it might be actually constructed from two back-to-back
diodes, he assumed you could connect the two anodes together (for an
NPN), call the joint the base and call the two cathodes the emitter
and collector.
Posted September 29,
2013 |