May 1948 Radio News
[Table of Contents]
Wax nostalgic about and learn from the history of early
electronics. See articles from
Radio & Television News, published 1919-1959. All copyrights hereby
Certain things about John T.
Frye are very apparent to the many of you familiar with techno-dramas - "Carl &
Jerry" and "Mac's Service Shop" - and his many magazine articles on topics related
to electronics and amateur radio: Mr. Frye has a good imagination, he is a
good story teller, and he has a very deep knowledge of electronics theory, troubleshooting,
repair, and practical operation. One particular about him you might not know is
that he spent most of his life in a wheelchair, as the result of polio. Born in
1910, John could not benefit from the
polio vaccine invented by Dr. Jonas Salk in 1955. That
was a mere three years before I was born. We are fortunate to live in these times
when so much amazing medical research is happening to prevent, treat, and cure diseases,
and while great advances have been made in rehabilitation techniques and prosthetic
devices. Societal accommodation of handicapped people has also become much more
There is a short, nice biography of
John T. Frye on the Copperwood Press website (near the
bottom of the page).
Mac's Radio Service Shop: Barney is Promoted
By John T. Frye
"How is that one, Mac?" Barney asked as
he set a gleaming radio chassis on the end of the bench.
Mac dropped his soldering iron in the holder and looked the freshly-cleaned chassis
"Not bad, Barney; not bad at all! In fact, you have been doing such a good job
in the cleaning department this past month that we are going to have to give you
a little promotion. It is time you learned how to replace parts. Now is a good time
to start, too, for this set I've been looking at is an example-and-a-half of how
not to do it."
He turned the set on which he had been working upside down and pointed an accusing
finger at a tubular electrolytic that had been bridged across an inverted-can condenser.
"There, my red-headed friend, is something I never want to see you do," he warned.
You mean to replace a tin can condenser with a paper one?"
"The words are 'inverted can' and 'tubular electrolytic,'" Mac said reprovingly.
"In learning a trade, the first thing to do is to learn the language so that fellow-mechanics
will know what you are talking about when you ask questions or try to explain something
to them. That business of calling a particular radio part a thing-a-ma-jig or a
doo-hickey is all right for a school girl, but it does not go around the shop."
"What is more," Mac went on, trying not to grin at Barney's crest-fallen appearance,
"I was not objecting to the use of the tubular condenser. They are okay. In many
instances, they make good and inexpensive replacements. The mistake was in not cutting
out the bad condenser from the circuit. The lazy guy who did this simply soldered
the new unit right across the old one."
"That's ungood, huh?"
"Very 'ungood!' An old condenser often has a low resistance. This low resistance
shunted across the new condenser increases its power factor, and a condenser is
one place where a high power factor is bad. What is worse, sooner or later the old
condenser is likely to short out - as it did in this case - and then the customer
has to pay two service bills for what should have been one job."
"But where do you tie all those wires that used to be soldered to the old condenser
after you take it out?" Barney wanted to know.
John T. Frye
Born 1910, near Weiner, Arkansas, moved to Logansport, Indiana in 1924, attended
Logansport High School, continued his studies at Indiana, Chicago, and Columbia
Has been in radio servicing since 1928. Started with a battery tester, a soldering
iron, and a confident look. Secured amateur license W9EGV in 1932 and radio has
since remained an avocation as well as a vocation.
Mac opened a drawer and picked up a handful of little one- and two-lug mounting
strips. "You use these," he said. "Often you can place the mounting-angle beneath
a nut, or you can solder it directly to the chassis. Then you can use the insulated
lugs for holding the connections removed from the condenser."
"Is there anything else wrong in that set?" Barney asked.
"What do you think?" Mac quizzed with a sidelong glance.
Barney's red head bent over the set as he inspected it gravely. "Wel-l-l," he
offered cautiously, "the terminals on that gadg - I mean that volume control seem
to have an awful lot of solder on them."
"Good!" Mac said. "I hoped you would notice that. And let me show you something
Picking up his soldering iron, he touched it to the lumps of solder on the volume
control terminals. As he touched each one, the wires attached to it dropped off.
"The fellow who put in that control must have been the world's laziest," Mac
said disgustedly. "He did not take the trouble to attach the wires firmly to the
terminals before soldering them. He just tacked them in place and then piled the
solder on to cover up. That is breaking the first commandment of radio servicing:
Always make your joints mechanically secure before you apply the solder."
"I catch; that saves solder."
"It saves more than solder, Barney; it saves you from getting sets back. In radio
work, solder is not used to hold things together. That is up the tinner's alley,
and he uses a different kind of solder. Radio solder is intended for the sole purpose
of making a good electrical connection."
As he talked, Mac was skillfully removing the caked solder from the terminals.
He held the point of his iron below each terminal so that when the lump of solder
melted it flowed down on the iron, and then he wiped it off on the wad of steel
wool he kept in a holder on the bench for that purpose. When the terminals were
clean, he inserted the proper wires in each, wrapped the ends tightly around with
his sharp-nose pliers, and then clamped the wires tightly in place. As Barney watched
him closely, he applied the bright tip of the iron to each for a few seconds before
he touched the rosin-core solder to the connection. The instant the solder touched
the heated wires it flowed smoothly over them in a thin, seamless coat.
"It takes just two things to make a good soldered connection," Mac explained.
"One is clean, bright surfaces; the other is plenty of heat. Most wires and terminals
you find in radio work are already tinned or can be easily made that way; so that
takes care of number one. A good soldering iron, properly tinned and clean, takes
care of number two. I have already told you how to tin the soldering iron, and don't
ever let me catch you with it any other way. That thin coating of bright solder
on the iron acts as a transfer agent to let the heat flow quickly from it to the
connection being soldered.
"If possible, always hold the iron below the connection being heated," he went
on. "Since heat rises, that speeds things up; but what is more important, excess
solder will flow down onto the iron and stay there instead of falling inside the
set where it could cause a short."
"I always thought you were supposed to pick up the solder on the iron and carry
it to the joint," Barney said.
"That is okay if you are working in a tight place, but if you have room for both
the iron and the solder - and you usually do - it is better to heat the connection
for a few seconds before touching the solder to it. When the wires are already hot,
the solder flows around them better. Don't take the iron away too soon, though,
for you want to be sure to boil out the rosin that sometimes collects around a wire
and makes a poor connection."
"Well," Barney said, poking around in the set, "here is one thing the character
did a good job on. This coupling condenser certainly doesn't have any long leads.
It is stretched tight as a fiddle string."
Without answering, Mac plugged the set in and turned it on. Then he tapped very
gently with his pencil the condenser Barney was admiring. Every time he touched
the condenser, the volume of the set would change abruptly, jumping first up and
"What's the matter there?" Barney asked resignedly.
"The leads on that condenser were pulled so tight that the continuous strain
has broken the connection between one of them and the foil. If he had left a little
bit of slack in the leads, this would not have happened."
"Did the joker do anything right?" Barney asked.
Mac looked at the set meditatively. "Well," he finally said, "he didn't burn
the insulation on any of the wires or melt the wax out of any of the condensers
by not watching where he was putting his iron. That is to his credit. A good serviceman
always clears things away and is careful so that his iron puts the heat just where
he wants it and only where he wants it."
"He was really a dope," Barney mused. "Say, whose set is this that took such
Mac picked up the tag and glanced at it. "It belongs to a Mr. Johnson at 2320
"Mr. Johnson! 2320 East Linden - Why that's - I was ·the one who - " Barney sputtered
and then stopped while brick-red flush crept up his neck and slowly spread over
his face until he looked like a summer sunrise.
"Yeah, I know; but don't let it throw you, son," Mac said kindly. "He told me
that he had let the young man next door work on it a couple of months, ago, and
I remembered that you lived at 2318 East Linden."
"I should have had more sense than to work on it - or better say butcher it up,"
Barney said bitterly; "but he kept insisting that if I knew enough to build a transmitter
I ought to know enough to fix a five-tube receiver. That's what he thinks - or thought!"
"That's one of the worst things about being eighteen," Mac mused. "You simply
can't say, 'I don't know'; you have to go ahead and prove that you don't know. Of
course, there is some faint hope for you. If you live long enough, you may just
possibly out-grow it."
At his teasing words, Barney's customary grin crept back across his face. "You
say the nicest things, Mr. McGregor," he murmured.
Posted December 3, 2019
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
Jameson his his eager, if not somewhat naive, technician assistant. 'Lessons' are
taught in story format with dialogs between Mac and Barney.