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In this installment on the continuing
technodrama of Mac's Service Shop, the subject of "Talking Books" comes up because
of a special type of record player (tape recorders were used, also) in for repairs.
The machine was a special design used by blind people to listen to books that have
been recorded by sighted readers. There is a least a bit of irony in how the two
were admiring the robustness of the design in order to cause as little inconvenience
to blind users, and yet there it was in the shop for repair! Little could Mac and
sidekick technician Barney have imagined how far the concept would have come by
today. While the physical volume, weight, and relative cost have come way down,
the capability and quality have skyrocketed. Reader devices today can do a real-time
text-to-audio translation, with some even able to turn pages as they go. The story
opens, though, with a lesson on being careful to determine that chemicals being
used are properly labeled and positioned in order to avoid the possibility of accidental
use.
Note the cover on this April 1959 issue of Radio & TV News magazine
states "Next Month to be Electronics World."
Mac's Service Shop: Talking Books
 By John T. Frye
The calendar said April, but the mercury sulking in the bottom of the thermometer
didn't believe it. Snowflakes brushed the windows of Mac's Service Shop and spread
a chilly, discouraging blanket over the timid, advancing army of new grass and its
brave but foolhardy leaders, the jonquils and the hyacinths. Mac was not surprised
to hear his red -headed assistant, Barney, charging through the front door. Anyone
would be in a hurry to get in out of that weather.
But apparently it was an idea, not the weather, that was spurring Barney.
He marched straight to the shelf where the various chemicals used in service work
were kept and picked out the pressurized can of acrylic spray. With great drama
he opened a cupboard door, placed the can inside, and shut the door firmly.
" 'Even madmen have their reasons,' " Mac quoted questioningly.
"I've got a reason, and a darned good one," Barney retorted. "I've just witnessed
a horrible catastrophe; and I'm making sure it doesn't happen here, especially to
me."
"Give!" Mac commanded.
"After lunch I decided to drop by and see my friend, Speed, who works at Acme
Radio and TV Service. We're supposed to double-date tonight and I wanted to work
out a couple of little financial matters in advance, without the girls around. You
dig ?"
"I dig," Mac said with a grin; "go on."
"Well, the boss was out, and Speed was keeping the store. While we talked, he
was trying to snow me with a demonstration of how fast he could service sets. First
he ran through a couple of real 'tough' troubleshooting jobs of locating burned-out
tubes in a.c.-d.c. receivers; then he slapped an all-wave chassis on the bench.
It would intermittently develop noise and cut out. Working the band-change switch
stopped this; so Speed tells me, as though I wasn't real bright: 'Here we have an
example of a band-change switch with dirty and corroded contacts. We can fix that
in a sec. All we have to do is pick up a can of contact cleaner and spray all the
wafers of the switch liberally, like so. Then we work the switch vigorously back
and forth a few times -'
"All at once he stopped talking and started to turn pale. At the same time he
began sniffing the air like a fireman on his day off getting a whiff of shingle
smoke. Then he looked down at that can he had been using with the same expression
of horror he would have had if it had been a rattlesnake that had just bitten him.
I already knew by the smell it was acrylic spray. He grabbed that switch and began
working it back and forth like mad to keep the gunk from setting up on the contacts
and locking the switch. At the same time he started squirting contact cleaner on
the wafers. I quietly tiptoed out of there and I'll bet he hasn't missed me yet.
Now you know why I moved that acrylic spray out of easy reach. It and the contact
cleaner are in the same sort of can and it would be very easy to get hold of the
wrong one as Speed did."
"That's using the old hatrack," Mac applauded as he turned back to the record
player on the bench.
"Hey, ain't that a kind of funny-looking record player ?" Barney asked.
"In a manner of speaking, yes. It's actually a Talking Book Reproducer used by
a sightless person. These special players were developed by the American Foundation
for the Blind. Various books and magazines - everything, in fact, from Reader's
Digest and current novels to Shakespeare and the Bible - are read onto long-playing
records by professionally trained voices; then, through the agency of the Library
of Congress and other organizations interested in the blind, these records and this
reproducer are made available on a loan basis to sightless persons. 'Talking Books,'
as the records are called, even go through the mails without charge."
"That looks more rugged than the average portable record player. I suppose the
metal guides are to allow the blind person to put a record on the turntable quickly
without being able to see; and this one allows him to lower the stylus onto the
record at the right point."
"You're right. This lever permits a choice of either 33 1/3 or 16 2/3 rpm. Between
these two positions, the drive wheel is disengaged from the turntable so that it
will not develop flat spots. A speaker is in the hinged lid. This is cut out when
phones are plugged into this jack for personal listening."
"What's the thing doing here ?"
"The owner says he can't hear it. He is hard of hearing as well as blind, and
he was afraid the reproducer did not normally put out enough volume. After all,
it is brand new and the first one he has ever used. But a letter from the Talking
Book people assured him there should be ample output, especially through the earphones,
to compensate for any except the most severe loss of hearing. They suggested he
take it to a competent electronics service shop for repair rather than return it
to them. This is a change of policy. They used to insist a defective machine be
returned for repair. This resulted in such long delays and in such frequent shipping
damage that now they suggest the sightless person have it repaired locally."
As he talked Mac turned on the amplifier with the switch on the tone control.
After a few seconds he used the switch on the gain control to turn on the turntable
motor. When the stylus was lowered onto the record, the voice could be heard very
faintly through the speaker. It was still faint through earphones plugged into the
jack on the motor board. The volume control had to be all the way on for useful
sound.
Working with unusual care, Mac took out the screws around the edge of the motor
board and then removed two others that went in through the bottom of the case. When
the motor board was lifted out, the amplifier chassis could be seen fastened to
the front edge of the board.
"Wow!" Barney exclaimed. "Look at that amplifier! That thing is really built.
I'll bet it has more parts in it than most a.c.-d.c. radios. It does a guy good
to see something like that after you are used to seeing some of the amplifiers -
often just one-tube jobs - that are used in cheap portable record players. Say,
isn't that a power transformer ?"
"Yep. This is no a.c.-d.c. job. The designer knew the sightless user would spend
hours at a time listening to it. After all, 'reading' a book usually requires listening
to both sides of twenty to thirty long-playing records. To listen for long periods
of time without undue fatigue means that distortion, hum, and other distracting
and extraneous sounds must be kept to an absolute minimum. That's why we see a heavy-duty
motor and turntable to keep wow to a minimum at the slow speeds; a power transformer,
full-wave rectifier, and lots of filter to reduce hum below the audible level; and
the employment of negative feedback in the three-stage amplifier to reduce distortion."
"And glory be!" Barney exclaimed as he peered over Mac's shoulder. "Right there
glued in the bottom of the case is a complete wiring diagram showing the values
of all components and giving the normal voltages measured at the socket terminals."
"Suppose we use that to see what's wrong," Mac suggested.
He started measuring the voltages at the socket of the output tube. All at once
he stopped with a puzzled expression. "Where's the cathode lug?" he asked Barney
as he stared at a blank spot on the socket where this lug should be.
"There it is floating in the air. It has broken off up inside the socket," Barney
pointed out.
He was right. The missing lug was supported by the leads of the cathode resistor
and bypass capacitor a good inch from the socket.
"Mmmmm! Changing that socket isn't going to be a snap," Mac observed.
"You ain't gotta change it!" Barney said quickly and ungrammatically. "I run
into this fairly often in hamming because I use the same sockets over and over again
in experimenting. All you have to do is punch out the broken lug and replace it
with a lug taken from an identical socket."
Mac stared at his assistant for a few seconds, and then a pleased grin flashed
across his face. "You're right! How stupid can a man be? If you hadn't spoken up,
I'm sure I'd have been dumb enough to change the whole socket."
Carrying out Barney's suggestion took only a little longer than it did to make
it and in a few minutes the new lug was in place and the floating connections were
soldered to it. When the record player was turned on, volume from the speaker filled
the whole shop; and the quality was excellent. Mac looked the amplifier over carefully
to make sure nothing else had been broken or shaken loose in shipping; then he carefully
replaced the motor board and put back the screws.
"Hey, Boss," Barney said quizzically, "do I imagine it or are you being even
more careful and gentle than usual with that piece of equipment ?"
Mac's forehead wrinkled a moment in thought, and then he said slowly: "I didn't
realize it, but you're probably right. This isn't the first Talking Book I've serviced
and returned to the user. If you could see the loving way those sensitive fingers
explore every square inch of the repaired instrument, you'd know it is much, much
more than just a record player to them; and you'd hate as much as I would to let
a slipping screwdriver put a gouge in that leatherette. What's more, you'd want
to be absolutely certain the Talking Book was putting out the topnotch performance
of which it's capable."
As Mac prepared to set the needle down on the record, Barney broke in with another
question: "Is that a turnover cartridge? I see a little lever sticking out the side.
Do they use one stylus for 33 1/3 and another for 16 2/3?"
"No, the same diameter stylus is used for both records; but this is a special
cartridge with a spare stylus built in. As you can see, the cartridge is held in
the arm by a simple spring clip. The little 'tongue' bearing the sapphire stylus
comes straight out the end. There are two sapphire styli on opposite sides of this
little tongue. When one is worn out, the sightless person, guided only by his sense
of touch, can remove the cartridge from the clip, turn it over and replace it so
the new needle is brought into service. The position of the little arm indicates
which stylus is in use."
The player was started, and the beautifully modulated voice of Alexander Scourby
reading "Conversation with the Earth" by Hans Cloos filled the service shop. As
he talked, Mac and Barney could see the great dark continent of Africa rising up
out of the sea like the surfacing of some monster of the deep.
"Man, this is the way to read!" he finally announced. "A book sounds a lot more
interesting when read aloud by someone who knows how to read. I can't imagine my
picking up a book written by a German geologist and translated into English and
wading through a whole chapter picked at random; but when Mr. Scourby reads that
same chapter aloud, he makes me determined to get that book and read the rest of
it. When I consider what electronics means to those sightless people, it makes me
feel kind of good that I'm a small part of electronics."
"That makes two of us," Mac said softly.
Mac's Radio Service Shop Episodes on RF Cafe
This series of instructive
technodrama™
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
Electronics
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. There
are 131 stories as of January 2026.
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