January 1955 Popular Electronics
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
published October 1954 - April 1985. All copyrights are hereby acknowledged.
Thanks once again to Mr. Ferrous
Steinke, quite the Carl & Jerry fan, for providing the following content.
"Biosonics as a repelling technique are based on acoustical signals emitted by
birds and other animals to convey information to conspecifics. Two audible bird
warning stimuli, distress and alarm calls, have been explored and/or used for acoustically
repelling birds from urban and rural roosts (Brough 1969, Pearson et al. 1967),
fish-rearing ponds (Spanier 1980), airport runways (Bridgman 1976, Blokpoel 1976),
agricultural settings (Boudreau 1975, Naef-Daenzer 1983, Summers 1985), and other
locations (Mott and Timbrook 1988). Distress calls are those emitted by birds when
being restrained, attacked by a predator, or subjected to other types of severe
conditions, whereas alarm or warning calls are usually given in response to the
presence of an intruder or predator. Depending on the species and situation, these
warning calls often cause conspecifics, and sometimes closely related species, to
leave the immediate area. The use of natural communication signals to frighten birds
has received considerable attention in the past several decades for managing certain
pest birds. They have the advantage of being more effective than the use of unnatural
sound and noises to repel nuisance birds as the birds do not habituate as rapidly
to the distance or alarm calls. Very little of this information was known or researched
Carl & Jerry: Operation Startled Starling
By John T. Frye
Jerry Bishop was in his basement laboratory busily trying to get the sound effect
of a horse plodding through deep mud down on the tape of a new recorder he had received
for Christmas. He was so engrossed in plopping a couple of his mother's cookie cutters
up and down in a shallow dish filled with water near the recorder microphone that
he scarcely looked up when the outside door was kicked open and Carl Anderson, his
neighbor and best friend, strode in carrying a bird cage held gingerly out in front
of him. "The next time you get a bright idea, Buster, you can do some of the legwork
yourself," Carl growled as he set the cage down on the workbench.
"Ah, you got one!" Jerry exclaimed as he shut off the recorder and strolled over
to examine the black, medium sized bird with beady eyes and rather ruffled plumage
inside the cage. "He doesn't look like he's hurt a bit. How did you ever catch him?"
"It wasn't easy. Some men were shooting the starlings with shotguns around the
courthouse, and that little buzzard had the ends of the feathers on one wing shot
off. That didn't hurt him any, but it sure messed up his flying. At that, I had
to chase him a couple of blocks before I caught him, and he managed to chew about
thirty cents worth of hide off the back of my hand while I was stuffing him into
the cage. Believe me, Old Scissorbill here is a crazy, mixed up starling; he thinks
he's an eagle or some other kind of meat eating bird."
"He does have a kind of nasty expression on his face," Jerry agreed as he looked
at the bird glaring defiantly up at him.
"This whole idea sounds strictly for the birds to me," Carl blurted out. "Tell
it to me again. Maybe it will sound better if I hear it once more."
"Last winter," Jerry patiently related, "a couple of zoologists at Penn State
College captured a live starling and made a 52 tape recording of its cries of distress.
Then the recorder was installed in a truck equipped with a public address system
parked beneath some trees infested with an estimated 20,000 starlings. After the
birds were settled for the night, the recording, tremendously amplified, was played
through the public address speakers. The birds awakened to the distressed screams
of one of their fellows, fled in terror, and never returned. We are going to try
to work the same thing on the starlings roosting in the trees in the back yard.
"Still sounds wacky," Carl commented; "but let's get on with it. You hold Scissorbill,
and I'll work the recorder."
"Now wait a minute," Jerry said hastily. "You'd better hold the bird and let
me operate the recorder. After all, you two are already acquainted. On top of that,
this is a pretty critical recording, and everything has to be just right. The tape
must be run at the right speed; the gain control must be set just so; the—"
"Oh all right," Carl said resignedly. "I didn't
really expect to get away with it, but it was worth a try. What do you mean the
tape has to be run at the right speed?"
"To make the bird's cries sound natural, we must have good high frequency response.
That means the tape will need to be run at its top speed of 71/2 inches per second."
"How come higher tape speed improves the high frequency response?"
"The recording head translates a sound wave of a given pitch into pulses of magnetic
energy that 'prints' the magnetic coating of the moving tape with regularly spaced
areas of magnetism. As the pitch or frequency of the sound goes up, these areas
are spaced closer and closer to each other until finally, when the frequency of
the sound wave is high enough, they start to merge together and so lose their separate
identity that must be maintained if the sound is to be reproduced naturally. Now
if we speed up the tape, this increases the separation of these magnetized areas;
and we can then increase the frequency of the sound wave considerably before the
areas start overlapping again."
While Jerry was talking he had removed the tape reels from the recorder and started
a short endless loop of tape running through the recording head. The microphone
was placed on the edge of the bench, and Carl cautiously opened the door of the
cage and reached inside for the bird.
"Yow!" he suddenly yelled as the starling viciously shut down on his finger.
"Shut up," Jerry callously commanded. "We want the starling's cry of distress,
not yours. We don't want to scare people."
Carl gave him a scorching look and then, angered, reached inside the cage and
hauled the bird unceremoniously forth. Holding it upside down by its feet, he dangled
it near the microphone while it screeched and screamed its protest at this treatment.
"That's fine," Jerry said. "Now let's see what we've got."
The recorder was switched to "Play," and instantly the basement was filled with
a loud cacophony of raucous screaming that even seemed to take Old Scissorbill aback.
At least he became quiet and listened attentively with his head cocked to one side.
"That certainly ought to do it," Jerry said.
"I don't know," Carl said dubiously. "That bird wasn't scared; he was mad. I'll
bet a nickel that instead of calling, 'Help, help!' he was really saying something
like, 'Let go of my leg, cuss you!' Can I wring his neck now?"
"Sure, but you won't," Jerry said with a grin on his round face. "You don't fool
me. I know how chickenhearted you are."
"Chickenhearted, my eye," Carl said with a fierce scowl. "However, I think I'll
just turn him loose and let a cat get him. That will be the kind of fate he deserves.
Wringing his neck would be too easy a death."
"Uh huh," Jerry said with a knowing smirk; "but now we've got to arrange a way
of putting some real punch behind this recording. I thought we could use that twenty
watt speech amplifier and modulator you use to modulate that command transmitter
of your ham station. Let's see, that modulation transformer has a 5000 ohm output,
"And here's the speaker I intended to use," Jerry remarked as he dived into a
corner of the basement and pulled forth a large speaker with a bell shaped trumpet.
"I've been hanging on to this for a long time hoping to find a use for it. This
job is rated at twenty five watts and has an eight ohm voice coil."
"Not a very good match for 5000 ohms," Carl observed.
"That's where this audio transformer will come in—I hope," Jerry said as he lifted
a heavy transformer on to the bench, "Someone gave me the thing, but no instruction
sheet came with it. The primary terminals are lettered, and the secondary terminals
simply are numbered from 3. to 16. However, by looking up this model in a catalogue,
I know the transformer is rated at twenty watts, that the primary is tapped for
use across either 3000 or 5000 ohms, and that the secondary is designed to feed
any voice coil impedance from one to thirty ohms. All we have to do is figure out
which primary and secondary taps to use so that our eight ohm voice coil will be
properly matched to the 5000 ohm output of the modulation transformer."
"How are you going to do that?"
"First, let's use the ohmmeter of our volt ohm milliammeter to measure the d.c.
resistance appearing between the various primary taps. Across terminals P-P we measure
600 ohms, while there is only 500 ohms across In-P1. We may safely assume that the
higher d.c. resistance indicates that the entire primary winding, designed for an
a.c. impedance of 5000 ohms, is connected between the two terminals marked "P".
"That's easy, but how about the secondary taps?"
"Well, we know that the impedance ratio between the primary and secondary of
a matching transformer is equal to the square of the turns ratio of these two windings,
"Our impedance ratio is equal to 5000/8 or 625/1. The square root of that is—"
Jerry settled back on the couch with his battered slide rule, but Carl interrupted
with, "Twenty five to one."
"You're right, you mathematical genius!" Jerry exclaimed as he double checked
with the rule. "We also know that if we put a certain a.c. voltage into one winding
of a transformer and then measure the voltage appearing across the other winding,
the ratio between the two voltages is equal to the turns ratio of the two windings.
So-o-o-o, all we have to do is put twenty five volts into the primary winding and
then measure the voltages appearing between the various taps of the secondary until
we find a pair producing quite close to one volt. When these two taps are found,
we can connect our eight ohm voice coil to them and be sure that when the whole
primary is connected to the output of the modulation transformer, we shall have
a complete match all the way around, which will insure a maximum transfer of power
with a minimum of distortion."
"Well, let's quit yakking and get with it," Carl, the man of action, said impatiently.
"Okay. This war surplus equipment filament transformer puts out almost exactly twenty
five volts of a.c.; so connect it to the primary of the transformer, and we'll start
measuring the voltages across the secondary taps."
In a matter of minutes the boys located a pair of secondary taps that indicates
precisely one volt on the .c. scale of their volt ohmmeter. The ends of a heavy
fifty foot extension cord were soldered to them, and the other ends of this cord
were fastened to the speaker terminals. The primary of the matching transformer
was connected to the secondary of the modulation transformer of Carl's amateur station
speech equipment. A phone plug with a six ohm, one watt resistor fastened across
its terminals was plugged in the "External Speaker" jack of the recorder, and a
shielded lead went from the two ends of this resistor to the high level input jack
of the speech amplifier. The six ohm resistor furnished a proper load for the secondary
of the recorder's output transformer when the unit's six ohm speaker voice coil
was automatically disconnected by plugging into the jack.
By the time this rather weird lash up of equipment was completed, the boys had
already received the third supper call; so they decided to suspend operations until
after the evening meal. Right after supper, though, Carl was back over wearing a
bright yellow slicker.
"There's a pretty good drizzle going," he announced.
"It takes a pretty mean guy to try and scare a poor little starling out of his
nice warm tree on a night like this," Jerry said teasingly
"Yeah!" Carl snarled as he rubbed his sore finger and made a threatening gesture
at Old Scissorbill, still resting in his cage; "I can hardly wait."
"Okay. You get outside the basement window, and I'll hand the speaker out to
you. That way our cord will allow us to get right under the tree with the speaker.
I want to be out there, too, when the fun starts; so I'm going to get everything
down here going but the tape recorder. Then I'll turn it on and dash out there with
you while the recorder amplifier is warming up."
This plan was put into action. Jerry switched on the recorder, flipped the volume
control well over to the "loud" side of its rotation, took a quick look to make
sure the loop of tape was going smoothly past the playback head, and then dashed
out the basement door, slamming it shut behind him. It was so dark in the back yard
that he stumbled into Carl before he was able to make out the yellow coated figure
of his friend standing there in the cold drizzle expectantly pointing the open mouth
of the loudspeaker straight up into the tree branches overhead.
For what seemed an interminably long time, nothing at all was heard from the
speaker; but then a beginning murmur of sound quickly swelled into a screaming roar.
Just as a photographic enlargement of some small, familiar object converts it into
a grotesque, unrecognizable thing, so did the great amplification of the starling's
screeching change the sound into a hoarse, brazen noise totally unlike anything
either of the awestruck boys had ever heard before. The thought flitted through
Jerry's mind that a dinosaur in his death throes must have made a sound like this.
Porch lights flashed on up and down the street, and shafts of light streamed across
back yards as rear doors were thrown open.
"Shut it off! Quick!" Carl screamed directly into Jerry's ear.
Released from his trance by this suggestion, Jerry turned and in a stumbling
run clattered down the basement steps and threw his weight against the door. It
did not budge. The night latch on the inside had locked itself. Hesitating only
a minute, Jerry bounded back up the steps with a vigor most unusual to his leisure
loving nature and ran around to the front of the house, through the front door,
down the hall, down the basement steps, and into his laboratory. He made a flying
leap across the room, and his clawing fingers switched off the tape recorder. Instantly
the bellowing stopped, only to be followed by shouting and the sound of running
feet going past the basement windows. Jerry turned off the basement light and stood
there panting in the darkness for a few seconds until he could regain his breath;
then he very quietly opened the outside basement door and tiptoed up the steps.
The back yard was no longer in darkness. Carl was sitting squarely in the center
of a blinding circle of light cast by the spotlight of a police squad car parked
in the alley; and two policemen, who seemed unnecessarily large, were getting out
of the car. Neighbors carrying flashlights were flitting around like fireflies.
"All right, all right," one of the policemen said, "which one of you called in
that 122-report about a dog being run over in this alley?"
"Yeah," his fellow officer chimed in, "and which one reported there was a panther
ten feet long slinking up and down and screaming its head off back here? Was it
you?" he demanded of Carl.
"No sir," Carl promptly replied. "I heard an awful noise, but I didn't see a
panther or hear any dog."
For a few minutes the policemen questioned the neighbors without getting any
two of them to agree on what the noise sounded like. Then they flashed the spotlight
all around, peered into a few garages and basement entrances, and finally decided
the whole thing was a false alarm.
"Probably some guy with a stuck automobile horn caused all this hullabaloo,"
one of them remarked as he got back into the squad car. "Sonny, you had better get
into the house out of this drizzle," he advised Carl as they started to drive away.
"Yes sir," Carl said meekly without moving.
Jerry sidled out to Carl and asked out of the corner of his mouth, "Where the
heck is the speaker?"
"What do you think I'm sitting on?" Carl demanded in a hoarse whisper as he spread
out the tail of his overcoat a little more. "I was scared to death they'd trip over
the cord, but they never even saw it."
In a few minutes the neighbors drifted away, and the boys got the speaker back
inside the basement.
"We'll not try that again," Jerry said emphatically; "and the heck of it is I
was too excited to notice if we scared any starlings or not."
"I wasn't," Carl answered. "While the cops were playing their spotlight and flashlights
around, I kept looking up in the tree. The birds did take off at first, but they
just made a little circle and came right back as soon as the noise stopped."
"Those Penn State starlings must be a timid, cowardly crew totally unrelated
to Old Scissorbill and his hardboiled chums," Jerry offered.
"Nope," Carl demurred, "I still think that pint sized eagle crossed us up. During
that hour or so while you were leisurely shutting off the recorder, I had to listen
to that racket coming right up in my face, and I'll swear that what Old Scissorbill
was yelling didn't sound like 'Take to the hills!' at all; instead, it sounded more
like, 'Hey, Rube! Come and help me take 'em!' "
""Well," Jerry remarked as he prepared to turn out the lights, "I guess Electronic
Experimenters, Ltd., will have to chalk this up as a howling failure—but it had
its moments !" END
Carl Anderson and Jerry Bishop were two teenage boys whose
love of electronics, Ham radio, and all things technical afforded them ample opportunities
to satisfy their own curiosities, assist law enforcement and neighbors with solving
problems, and impressing – and sometimes toying with - friends based on their proclivity
for serious undertakings as well as fun.
Carl & Jerry, by John T. Frye
Carl and Jerry Frye were fictional characters in a series of short stories that
were published in Popular Electronics magazine from the late 1950s to the early
1970s. The stories were written by John T. Frye, who used the pseudonym "John T.
Carroll," and they followed the adventures of two teenage boys, Carl Anderson and
Jerry Bishop, who were interested in electronics and amateur radio.
In each story, Carl and Jerry would encounter a problem or challenge related
to electronics, and they would use their knowledge and ingenuity to solve it. The
stories were notable for their accurate descriptions of electronic circuits and
devices, and they were popular with both amateur radio enthusiasts and young people
interested in science and technology.
The Carl and Jerry stories were also notable for their emphasis on safety and
responsible behavior when working with electronics. Each story included a cautionary
note reminding readers to follow proper procedures and safety guidelines when handling
Although the Carl and Jerry stories were fictional, they were based on the experiences
of the author and his own sons, who were also interested in electronics and amateur
radio. The stories continue to be popular among amateur radio enthusiasts and electronics
hobbyists, and they are considered an important part of the history of electronics
and technology education.
- Going Up
- March 1955
Shock - September 1955
- A Low Blow
- March 1961
- The Black
Beast - May 1960
Electronik, September 1958
- Pi in
the Sky and Big Twist, February 1964
Bell Bull Session, December 1961
Boogie, August 1958
- TV Picture,
Eraser, August 1962
Trap, March 1956
at Work, June 1956
Aweigh, July 1956
Has His Day, August 1956
- The Hand
of Selene, November 1960
or Not?, October 1956
Electronic Beach Buggy, September 1956
Extra Sensory Perception, December 1956
in a Chimney, January 1956
Performance, November 1958
of Judas, July 1961
- The Sucker,
New Year, January 1963
Snow Machine, December 1960
Extracurricular Education, July 1963
Slow Motion for Quick Action, April 1963
Sleuthing, August 1963
- TV Antennas,
a Soroban, March 1963
Fair --", September 1963
Worm Warming, May 1961
Operation Startled Starling - January 1955
- A Light
Subject - November 1954
Teaches Boy - February 1959
- Too Lucky
- August 1961
and Jeopardy - December 1963
Santa's Little Helpers - December 1955
Tough Customers - June 1960
Pocket Radio, TV Receivers
Yagi Antennas, May 1955
Stomping, March 1962
- The Blubber
Banisher, July 1959
- The Sparkling
Light, May 1962
Research Rewarded, June 1962
- A Hot Idea, March
- The Hot Dog
Case, December 1954
New Company is Launched, October 1956
the Mistletoe, December 1958
Eraser, August 1962
- "BBI", May 1959
Sound Waves, July 1955
- The River
Sniffer, July 1962
- Ham Radio,
Torero Electronico, April 1960
Wireless, January 1962
Electronic Shadow, September 1957
Induction, June 1963
- He Went
Detective, February 1958
an Instinct, December 1962
- Two Detectors,
with a Tachometer, July 1960
and the Pirates, April 1961
The Crazy Clock Caper, October 1960
Carl & Jerry: Their Complete Adventures is
now available. "From 1954 through 1964, Popular Electronics published 119 adventures
of Carl Anderson and Jerry Bishop, two teen boys with a passion for electronics
and a knack for getting into and out of trouble with haywire lash-ups built in Jerry's
basement. Better still, the boys explained how it all worked, and in doing so, launched
countless young people into careers in science and technology. Now, for the first
time ever, the full run of Carl and Jerry yarns by John T. Frye are available again,
in five authorized anthologies that include the full text and all illustrations."