Page 67 - The Art and Science of Analog Circuit Design

Thoughts on Becoming and Being an Analog Circuit Designer

your beautiful oscilloscope, spot-weld it to some part of your body so
that it is not borrowed without your knowledge.
I am an absolute hard-core fan of Tektronix test equipment. Tektronix
oscilloscopes (the most important item) are available with a wonderful
user interface and provide extremely high performance plus real versatil-
ity. The only problem is that they don't make that kind any more,
In recent years, there has been a trend toward computer-controlled,
menu-driven test instruments, rather than instruments that use a dedicated
switch or knob for each function (so-called "knob-driven" instruments).
In most cases, the push for menu-driven test instruments has an economic
basis—they are simply cheaper to build or provide more features for the
same price. However, there are practical drawbacks to that approach in
many cases. A common example, familiar to anyone who has ever used
an oscilloscope, is the frequent need to ground the input of a vertical
channel to establish a "zero" reference. With a knob-driven instrument,
a simple movement of the index finger and thumb will suffice. With a
menu-driven instrument, one often has to fumble through several nested
menus. This really sucks, and I think it is because they are starting to let
MBAs design oscilloscopes. (I suppose one possible benefit of this is that
soon 'scopes will have a built-in mode that tells you when to refinance
your mortgage!)
Grounding a vertical channel's input is something you need to do
often, and it is quite analogous to something familiar even to digital engi-
neers, like going to the bathroom. You simply wouldn't want to scroll
through a bunch of menus during your mad dash to the bathroom after
the consumption of a bad burrito! There are several similar annoyances
that can crop up when using menu-driven instruments (how about ten
keystrokes to get a simple sine wave out of a signal generator?!),
To be fair, menu-driven instruments do have advantages. However,
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since I am not a big fan of them, I'll conveniently omit them here, It
always pisses me off to watch students hitting the "auto setup" button on
the digital 'scopes in our teaching lab and assuming it is doing the right
thing for them every time (not!). If we didn't force them to, most of them
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would not even explore the other functions! Advertisements for these
new instruments often brag that they have a more "analog-like feel" (as
opposed to what, a "primordial slime ooze feel"?). Let's get real here ...
at least in part, this is just another incarnation of the old engineering say-
ing, "If you can't fix it, make it a feature." Since when was a "more
chocolate-like taste" a real key reason to buy brown sludge instead of
chocolate?

13. One of the key advantages is that they can help us lure would-be engineers into the lab. The type
of EE student who doesn't like hands-on hardware engineering (you know, the ones who end up
working for Microsloth) can be attracted by the nice menus long enough to actually see how
much fun electronics can be.
14. At this point, I will admit that our VCR does blink "12:00," but I hear there will be an
"auto-setup" mode on new ones! 1 had to fiddle with it for hours to get it to blink "12:00."

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