Always the consummate story
teller, John T. Frye began his writing career long before his "Carl & Jerry" electronics adventure series that ran monthly
for many years in Popular Electronics. His style featured creating a dialog
between instructor and student, serviceman and customer, husband and wife, father
and son, etc., in order to present an educational experience with back-and-forth
inquiry and responses. In the end, the reader learns something about both sides
of the situation. In this February 1955 story, electronics service shop owner Mac
McGregor reassures technician Barney Jameson that given time and patience, he will
grasp the circuit concepts of the newfangled color television sets.
Barney Takes on Color
By John T. Frye
What gives?" Barney asked as he stopped
short in the door-way of the service department that Monday morning.
"You mean you notice something different?" Mac, his boss, blandly inquired.
"I hope to kiss a pig I do," Barney retorted. "When did you do all this - and
"The wife went to visit her sister over the weekend," Mac explained, "and whenever
she is gone that darned house of ours seems as empty as a high vacuum rectifier.
To get away from it, I came down here to sort of look around when there were no
distractions - especially of the chattering, red-headed, Irish variety," he added
with a teasing grin.
"I'm overlooking that crack - for the time being," Barney retorted':
"It's kind of funny how a familiar place seen under different circumstances spotlights
things not normally noticed. I immediately saw several changes that cried out to
be made; so I spent the whole of Sunday making them.
"First, I put up that little shelf right at the end of the service bench. This
will now hold the few publications and sheets to which we refer constantly in our
work. I call it the 'First Aid Shelf' because the articles on it are calculated
to be the ones we shall normally consult before we turn to our service library.
For example, there are the four dial-stringing manuals. Nine times out of ten these
tell us all we need to know to replace a dial cord, and we do not have to go into
our service data files at all. Also there is an up-to-date tube manual giving complete
operating potentials, characteristic curves, and base diagrams of all tubes. You
know how often we reach for that. Naturally, the latest index to our service information
on radios, TV sets, tape recorders, and record changers is here. A glance at this
tells us at once if we have information on a particular piece of equipment and exactly
where to find it, together with any factory-suggested changes to be made in that
"Our record changer manuals will go here, too. As you know, many manufacturers
are pretty careless about listing the make and model number of a changer used in
their combination sets-especially when they do not make the changer themselves.
In such a case you can often spot a given changer quicker by leafing through the
record changer manuals and looking at the pictures than you can by trying to work
through service data cross-list-ings. Since about every changer that comes in can
stand a minor adjust-ment of the needle set-down points, the tripping mechanism,
etc., I think having the manuals right at hand will speed up this work. In addition,
there is a sheet showing interchangeable portable batteries of different makes and
another giving interchangeable phono cartridges. These allow us to carry a single
line of each of these items and still be able to service most record players and
portable, receivers that come into the shop-and to do it quickly and accurately.
"Finally, there is a good wholesale radio and TV parts catalogue. The illustrations
and descriptions contained in this can be a great help to a technician in selecting
a needed repair part or tool, even though he does not order from the firm putting
out the catalogue. He can see side by side the offerings of competitive manufacturers
with concise and accurate descriptions of each product. What's more, the catalogue
gives him a good idea of what a fair price for the item should be. An intimate acquaintance
with a good wholesale catalogue permits a technician to buy much more intelligently
than is possible otherwise."
"As I get it," Barney said, "this 'First Aid Shelf' is to contain only the articles
we use a lot. It is to be a sort of Reader's Digest of our service library."
"That's it exactly," Mac applauded; "and now let's turn our attention to this
adjustable lamp clamped to the edge of the bench exactly between our two working
"Is that what that is!" Barney marveled. "I thought it was an overgrown modernistic
sculpture of a praying mantis."
"There is a resemblance," Mac grinned as he looked at the folded, spring-loaded
arms holding the deep shade of the lamp. "I firmly believe a service technician
can never have too much light - either intellectual or actual - while doing his
work. I'm doubly sure of this whenever I cut loose a wrong lead because I can't
see clearly. Our overhead bench lights give all the light we need when the chassis
is turned upside down, and of course we have various flashlights for looking into
dark corners; but most TV chassis must be worked on while they are lying on their
sides, and record changer action frequently must be watched while the changer is
right side up. This new lamp gives a flood of light exactly where we need it and
leaves both hands free at all times.
"Just look how it can reach out to any part of the bench and throw the light
in any desired direction. That's because those folding arms extend out to forty-five
inches and the lamp itself is mounted on a swivel. Notice, too, that while the lamp
can be moved into any position with a touch of the finger, it stays exactly where
you put it. When you want to watch a record changer going through its cycle, the
lamp will get right down on its knees and peer up into the mechanism with you. If
you drop something, the lamp will bend over so the bulb is nearly touching the floor
to help you look for the dropped object. When you are taking a set out of a cabinet,
the lamp will reach away out from the bench and throw a strong light over your shoulder
or up into the speaker compartment to aid you in locating screw slots, and so on."
"Man, that thing has got more movements than a can-can dancer," was Barney's
Mac passed over this and went on to point out little plastic dishes mounted along
the back of the service bench beneath various instruments.
"You know what a fan I am for all sorts of special probes to use with our instruments.
I think we've got about every kind of probe you can mention, but we've not had a
handy way of storing them. They've all been kept in a drawer where they have a nasty
way of getting their leads tangled up. In fact, there have been times when you were
trying to sort out a probe from this mess where I couldn't be sure if you were doing
service work or trying to weave a fishnet. What's more, it was not always easy to
remember which probe was designed for use with what instrument.
"That's a thing of the past now. Beneath each instrument you see a deep little
plastic dish I bought at the dime store. Probes for each instrument are stored in
its individual dish. For example, below the vacuum tube voltmeters we have a crystal
probe for reading r.f. voltages, a high voltage probe for going up to 30,000 volts,
and a peak-to-peak probe. The new v.t.v.m. reads peak-to-peak voltages directly,
but this probe lets the older meter do the same thing. Under the signal tracer we
have the r.f. crystal probe and the straight-through audio probe. Beneath the scope
we have the demodulator or signal tracer probe, the 100/1 voltage divider probe,
and the low-capacity probe, together with the single shielded lead that fits all
three probe heads. The dish under the sweep generator doesn't hold probes but in
it are stored the various special leads that go with this instrument. It is my fond
hope that having these probes ready to hand will encourage you-know-who to use them
more often. What's more, I want you-know-who to fold the probe leads up neatly and
snap rubber bands around them to keep them in place when he is through using them."
"Roger from you-know-who. Wilco. Over and out," Barney chanted.
There was a brief silence finally broken by Barney:
"Say, Mac, I'm having a rough time trying to bone up on color TV. I've been reading
everything I can get my hands on, but I just can't seem to nail it down the way
I'd like. There seems to be so much repetition, conflicting analogies, etc., in
the articles I've been reading that I'm downright confused. It's not that I'm not
trying, either. I think about color TV so much that when I go to bed I even dream
Mac chuckled at this as he went over to a cabinet and took out a large bulging
manila envelope. "I've been waiting impatiently for you to display interest in color
television," he remarked, "but I didn't want you to feel I was pushing you into
it. In this envelope is a complete nine-lesson home study course just for you!"
"When I finish the course, I'll know all I need to know about color TV, huh?"
"Not by a long shot. I intend for you to use this course as a kind of basic framework
on which you will hang all the other things you will be continually learning about
this fast-moving, far-from-simple subject. I know it will help you to approach color
television in the carefully-planned, step-by-step procedure presented by this course;
but there are bound to be many points that will not be crystal clear even after
the course is finished. That's where your supplemental reading of magazine articles
should help. Each writer sees things a little differently and writes about them
from a different point of view. By reading what two or three of them have to say
on the same subject, you often see quite clearly something that was a big mystery
the first time you read about it.
"Speaking of magazine articles, I don't think you will find any much more helpful
than those written by Milton Kiver in Radio & Television News, starting with
the March, 1954, issue. I think he calls the series 'Fundamentals of Color TV.'
One thing I like about the articles is that Kiver takes time at the end of several
of them to prove mathematically puzzling general statements made in the body of
the articles. I think you'll be surprised at how much more useful and informative
a series of articles like this seems when you have several of them on hand and can
refer back and forth through them and through your course, instead of just reading
them one at a time, with a whole month elapsing between readings."
"You would help a guy out with his homework if he got stuck, wouldn't you?" Barney
"Yes, if I could. But you've got to remember that when it comes to color TV I'm
just a student same as you are; but we'll sure do our darndest to puzzle it out
Posted July 14, 2022
(updated from original post on
Mac's Radio Service Shop Episodes on RF Cafe
This series of instructive stories was the brainchild of none other than John T.
Frye, creator of the Carl and Jerry series that ran in
Popular Electronics for many years. "Mac's Radio Service Shop" began life
in April 1948 in Radio News
magazine (which later became Radio & Television News, then
World), and changed its name to simply "Mac's Service Shop" until the final
episode was published in a 1977
Popular Electronics magazine. "Mac" is electronics repair shop owner Mac
McGregor, and Barney Jameson his his eager, if not somewhat naive, technician assistant.
"Lessons" are taught in story format with dialogs between Mac and Barney.
Color and Monochrome (B&W) Television