This episode of "Mac's Radio Service Shop" goes down a drastically
different path than most, at least until the very end where
a completely unrelated anecdote about interference with a remote
garage door opener is told by Mac. Although the exact issues
chanted by electronics technician cum repairman Barney Gallagher
regarding many manufacturers' penchant for designing and selling
unserviceable equipment is dated, the principle remains the
same. We have all wished a designer had to service the product
he/she has designed and sold to us.
Mac's Radio Service Shop: The Worm Turns - and Squirms
By John T. Frye
Mac had to stop at the bank during his noon hour, so he was
a little late getting back to his service shop. When he finally
did step in out of the raw January wind, the outer office was
empty; but he could hear Matilda Perkins, the office girl, giggling
like a high school freshman back in the service department.
Walking softly across to the door, he opened it upon a strange
Barney, his assistant, was sitting cross-legged on the service
bench, his red thatch of hair concealed beneath an improvised
turban of paper towels. In his left hand he clutched a small,
misshapen doll, and with his right hand he was repeatedly thrusting
a sharp scribing tool into its soft body. All the while he kept
muttering to himself in a low monotone. Matilda was perched
on a service bench stool in front of him trying to stop her
almost hysterical laughter by cramming a handkerchief into her
"What's with Balmy Barney now?" Mac asked her.
"He's getting rid of his inhibitions," she managed to gasp.
"I never thought he had any," Mac said; "but how does all
"He read in a magazine that children often can be freed from
their secret hates and angers by allowing them to deface and
destroy pictures of people they dislike," Matilda explained,
wiping her eyes. "He says if that's good for kids it ought to
be good for him, too; so at noon he bought that kit of modeling
clay and made that little man-figure that stands for all the
manufacturers, engineers, and production men who dream up radio
and TV sets that are hard to service. Now he's punishing this
effigy and so ridding himself of a suppressed desire to commit
mayhem on the persons of these men."
"Sounds like witchcraft to me," Mac commented as he sat down
on the other service stool and picked up a lump of the colored
Like most good Irishmen, Barney Gallagher had a little of
the ham (sock-and-buskin as well as key-and-mike variety) in
him, and he was playing this scene to the hilt and way beyond
- say about half-way to the elbow. He had sat silent with his
chin on his chest like a brooding Buddha during this exchange
between his boss and Matilda, but now he took up his sing-song
"So you will run leads from a set down through a hole in
the cabinet shelf and then solder them to the speaker so a man
has to use a soldering iron just to get the chassis out, will
you? And how about that business of stapling loop antennas into
console cabinets? Too cheap to use a couple of wood screws,
aren't you? But when it comes to putting backs on console and
TV cabinets you don't mind using screws. Oh no! Then you throw
in one about every two inches so a poor guy has to take out
a whole hatful of them just to change a tube. Speaking of antennas,
my bucko, this jab is for cementing a loop inside a plastic
cabinet and then using short leads soldered to chassis connections
so a party can't even pull out the chassis and turn it over
without breaking those solid-wire leads. Why couldn't you fasten
the loop to the chassis where it belongs? You knew that putting
the chassis back into the case, into the field of the loop,
would upset any alignment done outside; yet you made no provision
for reaching the alignment screws with the set in the cabinet.
Another prize crock you have pulled is in mounting a loop with
its turns wound in a horizontal plane. You certainly should
know that the only way a customer can pick up any but the stronger
vertically-polarized signals on that loop is to turn the set
on its side.
"This gouge is for the crimes you have committed in the name
of dials and dial-drives. Take the case of those transparent
dial covers that are riveted to metal or celluloid backing plates
with only room for the pointer to move in between. How do you
think the technician is going to clean those dial covers? Do
you think he is going to remove and put back all those eyelet
rivets each time, or did you intend for him to replace the whole
works every time the cover got dirty?
"Another thing: are you trying to see how much you can overload
a poor little dial cord? You rig up contraptions requiring the
dial cord to turn the tuning condenser, work a slug-tuning assembly,
move a pointer back and forth, and revolve forty-eleven pulleys
besides - and sometimes you are too tight even to use wooden
pulleys! You know that cord will start slipping on the shaft
before the set is out of the store a month. If you can't make
the thing work longer than that, how do you expect the technician
to do so?
"Take that and that for the things you have done with record
changers! Only a bird with malice in his heart would ever design
a changer that must maintain tolerances and clearances to a
few thousandths of an inch and then make the thing out of warping,
wearing pot metal. . All you want to do is get the thing out
of the factory. A lot you care if it is impossible to keep
in adjustment in the field. You prove that again by cooking
up a changer design that taxes every last ounce of power of
the phono motor. When everything is clean and brand-new, the
motor barely has enough power to complete the change cycle;
but as soon as a little gum forms in it and the drive wheel
loses a tiny bit of its traction, the motor no longer can do
the job. You never thought of designing in a little reserve
of power, I presume."
Barney stopped for breath, and Mac reached over and took
the sharp-pointed scriber out of his hand.
"Let me try a little of this voodoo stuff," he drawled as
he held up a little figure he had molded from various colored
bits of clay while Barney was talking. "Now this little figurine
stands for a few technicians I have known in my time and who
have gotten into my hair more than somewhat in that period."
"The first sharp prick we give you, my friend," Mac said
to the little clay doll, "is to deflate your ego. I often hear
you heaping fine scorn on radio and television manufacturers
for the mistakes they have made. You never give these men any
credit for having to meet competitive prices and for not having
limitless time at their disposal for working out every last
bug from a new model. You do not seem to realize that you are
second-guessing all of these errors. They might prove to be
a lot harder to see if you were depending upon foresight instead
"And this prod is for your doing all your yelling where it
will do no good. If you see a mistake has been made in the design
of a chassis or a record-changer, why don't you sit down and
write a courteous letter - not one of the smart aleck, how-can-you-be-so-dumb
type - to the manufacturer telling him what you have found and
making suggestions for correcting the trouble? You may be surprised
at the appreciation he will show, and you can be certain he
will not repeat the mistake in future models.
"I might suggest, too, O Bumptious One, that sometimes you are
guilty of trying to blame your own lack of service skill and
enterprise on to the set-maker. Time after time I have seen
your kind try to persuade yourself that a poorly-operating set
never did work any better, that it was made that way; consequently,
nothing could be done about it. How you can make yourself believe
anyone would pay his good money for a new receiver in that condition
I'll never know. If you would concentrate more on improving
your own knowledge and technique instead of always being so
alert to catch the manufacturer off base, you'd be a better
technician for it."
"Hey, lemme see that technician-doll of yours," Barney demanded
as he grabbed it from Mac's hand. "Uh huh, it's just as I thought.
Did you have to make him with red hair?" he asked plaintively.
"You know," he went on reflectively, "I'm beginning to think
there is something in this voodoo stuff after all. I could have
sworn that I actually felt some of those jabs you gave this
"Imagination - and a guilty conscience - can play strange
tricks," Mac commented; "but let's get away from all this hocus-pocus
and talk a little sense. I ran across something yesterday I
think may interest you. A fellow came in with the complaint
that his radio-controlled garage door had suddenly become very
erratic in its behavior. It opened and ·closed of its own accord
while the car that had the controlling transmitter was miles
away and the transmitter was shut off.
"I went over and checked the thing over carefully, but I
couldn't find a thing wrong with it: a good healthy signal from
the transmitter was required to trip the pilot relay; there
were no gassy tubes to cause trouble; running the line voltage
up and down made no difference. First thought of mine was that
possibly a harmonic of a ham transmitter was getting into the
receiver and making the relay trip, for I have read of that;
but since Ten went dead none of the local gang are working the
high-frequency bands; so I decided to look for something else.
I asked the man if any new electronic equipment had been installed
in the neighborhood lately, and after I explained what 'electronic
equipment' was, he said all he could think of was a new TV set
in the house across the street that had been in for a couple
"Playing a hunch, I went over and asked the folks if they
would mind turning on their TV receiver for a few minutes. As
I stood in front of the receiver I could see the closed garage
doors; and when I turned the channel selector to Channel 10;
the doors opened up. I tried it two or three times, and every
time the set was tuned to Channel 10, the doors worked. With
the i.f. used in that set, the oscillator was on about 219 megacycles
when the receiver was tuned to Channel 10, and that is squarely
inside the 210-250 megacycle band in which the door-opener works.
Fortunately, provision had been made for using any one of six
different frequencies in the garage-door setup; so I just moved
the transmitter to a different frequency and peaked up the receiver
on that. When this was done the TV set could be switched to
any channel without affecting the doors."
"That is one for the book," Barney said; "and it just goes
to show you what a hefty signal is radiated from the oscillator
of some of the TV receivers. No wonder we hams get the blame
for a lot of blanking out and herringbone patterns that are
caused by a neighbor's TV set tuned to a lower channel!"
Posted January 20, 2016
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 Radio & Television News
magazine (which itself started as simply Radio News), and then changed
its name to Mac's Service Shop after the magazine became
World. 'Mac' is electronics repair shop owner Mac McGregor, and Barney
is his eager, if not somewhat naive, technician assistant. 'Lessons' are taught
in story format with dialogs between Mac and Barney.