The manuals for the higher end units can be as many
as 400 pages, and require more time to read and study.
Of course, you will need to refer to the manuals often for
the seldom used functions and procedures that slip your
Most will perform just about any operation you can
imagine within their intended purpose, but may be slow to
set up even for a quick simple test. The worst part of all
this is that certain TE is almost impossible for the average
(or even way above average) enthusiast to work on.
Even finding part’s locations can be very time-consuming. With the ever-increasing board population of
SMD parts along with parts getting tinier every succeeding
year, your chances increase of causing more problems in
the troubleshooting process than the one problem you are
originally trying to fix. The traces are so small and close on
a lot of these boards that one minor twitch of the test
probe can wipe out several circuits. Without “smoke,” you
will never know it happened, so you are still looking for
one problem when, in fact, there are now multiple issues.
Many of these units may have a fairly large footprint
and will take up a lot of valuable bench real estate, so all-in-all are better suited to large research centers.
The only occasion I had to repair this type of
construction was when I was called to troubleshoot a late
model microwave baseband modem, of which (in older
models) I was very familiar with. Upon opening the bottom
panel, I could not believe my eyes. It looked like the board
had been coated with glue, and then a pound of rice
pored over it and set to dry. These were SMD parts of the
“04” size. I could hardly tell where one part ended and the
next one started. I just closed it up and walked away.
My point is that I would never want to own newer TE
with this type of construction. If it went sour on me or
was that way to start with, I could never make it right.
Even in original manufacturing, human hands cannot
construct these boards, so that is left up to robotic “pick
and place“ machines.
Now that I have covered good reasons not to buy
newer equipment, let me talk about good reasons to buy
older TE. For the most part, this equipment will have
features and quality specs that will probably be much
more than adequate for any project you use it on. They
will use through hole or stand-alone parts that are easy to
locate, identify, and replace in regards to repair and/or
calibration. Although somewhat lacking the accuracy and
features of their more modern “brothers,” they are simple
to use and fast to set up for quick tests. They require no
software (or proprietary software). In short, they are a
much more repairable unit than newer TE.
One caveat here is that even though most of the parts
are of the over-the-counter type, some will be difficult or
impossible to obtain. Hewlett-Packard may have an
occasional “hybrid“ part in their units. Hybrids are special
circuits that are made up like an IC by using discrete
components, and are usually sealed in a metal container,
One item I have not mentioned that sooner or later
will be essential is the operator/service manual that rarely
comes with used equipment. This makes correct usage on
the TE so much easier to learn, plus the repair instruction
and road maps for locating parts are essential. Also,
calibration and proof of performance tests give peace of
mind when everything meets factory specs. You can go as
far as needed or desired with whatever TE you have on
hand to do this. There are some specs that you would
need a boxcar of test apparatus for checking, but a lot of
them are (for the most part) of minor importance for most
of us and not of great concern for everyday use.
These manuals can go for $25 - $40 apiece, but there
is a website called BAMA (Boat Anchors Manual
Association) that has a ton of manuals for free download.
You can always research the Internet for any information
floating around out there, or check out Internet services
that sell manuals on discs for $5 - $15. My favorite here is
ARTEKMEDIA. They’re a little higher in price, but provide
excellent reproduction work. I have printed up manuals
from their discs that rival the best of the originals.
Now, it’s time to start buying. Although I have
cautioned you about buying newer TE and sticking with
the somewhat older equipment, nothing is engraved in
stone here. You may find newer stuff that was made to
order for you at a decent price and guaranteed. Also,
there is equipment dating back to the early ‘60s that has
excellent specs and a proven track record. The Tektronix
“500” series scopes and the Hewlett-Packard “600” series
RF signal generators are all solid performers. They are a bit
power hungry with their tube design with bulky
transformers and, of course, are quite large and heavy by
Odds are that any used TE will have some defects.
This could be as simple as a blown fuse, burned out pilot
light, or an ugly scratch on the front panel, or something
more involved on the interior. The TE I have purchased on
eBay all had problems, but basically they were minor. A
bad power supply, for example, could be lytic, have dirty
connections, a bad power switch, or others. All of these
are simple fixes to get it working.
Once the unit is powered up and working, I will take
a very quick assessment of its operating condition, such as
if the mechanical controls are operating okay and if basic
functions are at least working. Then, I get busy with a can
of contact cleaner and scrub all mechanical parts
including accessible connectors.
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