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December 1956 Popular ElectronicsTable of Contents
People old and young enjoy waxing nostalgic about and learning some of the history of early electronics. Popular Electronics was published from October 1954 through April 1985. All copyrights are hereby acknowledged. See all articles from Popular Electronics.s from Popular Electronics.
Carl and Jerry were early adopters of the near field communications (NFC) craze that is going full-swing today. The often harmlessly mischievous teenage duo used their combined grasp of modern electronics to pull off gags on unsuspecting friends... and sometime adversaries. In this episode, a near-field transmitter and receiver pair is designed to help Carl bedazzle a scientist who was attempting to disprove the ability to use extrasensory perception (ESP) to determining what another person was thinking about. In this case it was detecting which playing card was being displayed on an overhead projector. Of course Carl didn't really have 'the gift,' but relied on his co-conspirator, Jerry.
Carl & Jerry: Extra Sensory Perception
By John T. Frye
It was a bleak Saturday afternoon in early December and Carl and Jerry were sitting in Jerry's basement doing absolutely nothing. This was most unusual, for the two were generally busy at something or other. But there they were: Jerry sprawled on the old leather-covered couch along the wall; and Carl sitting across the workbench, elbows on knees and chin propped on hands.
"Hey, Jer," Carl finally drawled, "do you have trouble staying awake in that second period assembly?"
"Sure do," Jerry said with a reminiscent yawn. "Guess neither of us needs to do much studying in there, and there's nothing else to do. Even the surrounding scenery is no good. Did you notice the girls who sit on both sides of me? Real beasts!"
"Naw, I don't pay any attention to girls," Carl said, just a trifle too emphatically; "but I wish we had something to do in there. If we could just talk to each other some way-"
He stopped speaking as Jerry suddenly swung his feet to the floor and sat upright on the creaking couch. '''That's an idea!" Jerry exclaimed. "Why don't we build a couple of little transmitters and receivers and chew the fat during that period instead of wasting time?"
"Well, I dunno," Carl said doubtfully .
"We'd have to use code instead of phone, and it would have to be doggoned quiet code at that. You know how still that crabby old Miss Dean keeps things in that study hall. I've seen her send kids to the office just for shuffling their feet."
"Yeah, that's right," Jerry said thoughtfully. "We couldn't use earphones, even the hearing-aid type. She would certainly spot something like that."
"If we just had some system so we could feel the signals instead of hear them-" Carl started to say.
"That's it!" Jerry interrupted. "We'll use a low-frequency note to modulate the transmitter. The receiver will amplify this and feed it to a diaphragm-type earphone with the diaphragm taped right against a sensitive portion of the skin. With a little practice, we should be able to interpret the buzzing sensation produced by dots and dashes just as well as we could if we were hearing an audible note."
"What kind of transmitter and receiver will we need?"
"Transistor types in both cases in the interest of small size and low battery drain," Jerry promptly said. "I think the receiver should be a regenerative detector with a couple of stages of audio behind it to furnish plenty of drive to the earphone - or perhaps we should call it a 'skin-phone.' The transmitter will consist of an r.f. oscillator modulated by a low-frequency audio oscillator. We'll key this audio oscillator and let the r.f. generator run all the time. Since we'll only be working over distances of a few dozen feet, no antennas will be necessary."
"What kind of a key can we use?"
"A tiny one made with a couple of pieces of spring brass will be good enough. The leads from this can run through a shirt sleeve so that the key can be concealed in the palm of the hand and worked by simply squeezing the contacts together. After all, we won't be sending thirty-five words per, minute. When the key isn't in use, it can be slipped back inside the shirt sleeve."
"Well, let's get started!" Carl suggested, hopping off the bench. "I want to have this thing ready to go by Monday, and if we don't run into some bugs that need ironing out, it will be the first time."
This time was no exception. The receivers gave no trouble; but the transmitters made up for it. Even at the low frequency used-around 550 kilocycles - the oscillators were sluggish. They tried several circuits before they found one that was stable in performance and would accept modulation from the low-frequency oscillator. Finally, though, by late Sunday afternoon the problems were all apparently licked, and the boys were ready for a trial. Each boy had a small earphone, with its cap removed, taped to the inside of his upper right arm so that the face of the diaphragm was flat against his skin. A tiny transmitter was carried in one shirt pocket, a small receiver in the other.
"Are you ready?" Jerry asked, as he looked across the laboratory at Carl.
"Fire at will!" Carl answered.
Jerry started squeezing the "key" concealed in the palm of his hand, and Carl flinched and began to giggle. "Hey, that tickles!" he announced, "but I can make out your 'CQ' all okay. Try something else now."
Jerry began tapping out the dots and dashes to ask: "Can you read this?" And he jumped in turn as Carl promptly came back with the "dit-dah-dit" of "received okay" followed by the "dah-dit-dah-dit" that means "yes" in the code used by amateurs. In the few minutes remaining before supper, the boys found that they could easily work each other up to about a hundred feet. Then they had to lay their new playthings aside.
The next morning their mothers did not have the least trouble getting them started off for school; but oddly enough, the boys did not walk together as they usually did.
Instead, they went down opposite sides of the street, with faraway looks in their eyes and their right hands working spasmodically.
It was during the second period study hall that they had the opportunity to give their brainchild the acid test. As soon as the bell had rung and everything was quiet, Miss Dean started her gimlet-eyed stroll through the aisles. Just as she walked past Carl's desk, Jerry tapped out: "What a sour-puss!" He did not need to feel the buzzing acknowledgment against his arm; Carl's heaving shoulders told clearly that he had got the message.
The boys had a real picnic during the study period sending messages back and forth. Every boy is a lodge brother at heart, and the fact that what they were doing was secret and entirely unnoticed by others in the room added tremendously to the flavor of the accomplishment. Time went very fast, and just before the end of the period, the voice of the principal boomed through the loudspeaker on the wall announcing: "Instead of going to your next class or study hall, all students will proceed to the auditorium for a special program to be presented by Professor Karns of the psychology department of our state university."
The boys' study room was directly across the hall from the auditorium; consequently Carl and Jerry were in the vanguard of the thundering herd that surged through the doors of the auditorium. As a result, they were seated in the second row from the stage when the curtains parted. .A dapper man wearing pince-nez glasses stepped to the proscenium and said:
"Good morning, students. The program that you will see now is going to be a little unusual. To some of you it will be quite interesting. Others will find it dull. What you think of it does not really matter. You are going to be permitted to take part in an experiment in what is known as 'Extra Sensory Perception.' There is a growing belief in some quarters that a certain amount of information can be transferred from one mind to another without the aid of any of the usual senses. To check the validity of this belief, our psychology department is conducting experiments, such as the one in which you are about to participate, at various high schools and keeping a careful record of the results. Out of these experiments, we hope to arrive at some definite conclusions as to whether there actually is such a thing as 'ESP' or not.
"To go on with the experiment, I shall need an assistant. Experience has taught me that it is useless to call for volunteers from a high school group; so I'll draft one of you. Let me see now. The tall young man wearing glasses in the second row looks like a bright chap. Will you please come up here, young man?"
Hands on all sides, even those of his buddy, boosted a reluctant Carl to his feet and shoved him out into the aisle.
He walked awkwardly up the steps to the stage and faced the professor.
"Don't look so frightened," the professor said jovially. "This is not going to hurt a bit. You are familiar with the names of a deck of playing cards?"
"Yes," Carl said in a small hoarse voice. "Fine! I want you to stand right here at the front of the stage facing the audience. On the elevated screen at the back of the stage I'll show a card at a time with this projector. As each card shows on the screen, I want all of the students to concentrate on its name and suit as hard as they can for five full seconds. At the end of that time I shall strike this little bell, and I want you to name the first card that comes into your mind. For example, you may say, 'Ace of diamonds,' or 'Nine of clubs,' or whatever card is in your mind at the second you hear the bell. What we shall be trying to do is to transfer the knowledge of the card directly from the mind of the audience to your mind. A young lady back in the wings - she is too, pretty to have on the stage because she would distract attention from the experiment - will keep a careful record of each card shown and the cards you name.
"But let me warn the audience not to expect too many correct identifications. The odds against your correctly naming even one card are tremendous, and it is against these mathematical odds that we are competing. If you can better the law of probability by just a little, it will be significant."
Jerry was watching Carl closely, and he saw the latter's mouth draw into a straight line that meant he was not taking at all kindly to the glib man beside him. Jerry did not like him either. He sounded too much as if he were trying to be "cute," as though he were talking down to his youthful audience.
The lights were lowered, and suddenly a huge queen of spades appeared on the screen above and behind Carl. With a sudden inspiration, Jerry squeezed the little brass contacts already held in the moist palm of his hand to spell out "QS." As he finished the last dot, the bell tinkled and Carl promptly said in a loud voice: "Queen of spades!"
"An astounding, auspicious beginning!" the professor exclaimed. "Let's try another."
He flashed the seven of hearts on the screen. Jerry immediately tapped out "7H," and Carl called out: "Seven of hearts!" the instant he heard the sound of the bell.
"This places too much of a strain on coincidence," the dapper man said in a suspicious, harried voice. "Maybe you can see some reflection of the screen, or perhaps some smart aleck in the audience is signaling you in some fashion. Would you mind letting me blindfold you?"
"Go right ahead," Carl said in return.
After a moment of indecision, the scientist won over the fashion plate, and the professor removed the handkerchief that was peeping meticulously from his breast pocket and securely blindfolded Carl. Then he went back to his projector and flashed the jack of spades on .the screen. Carl easily translated the dots and dashes of "JS" buzzing against his arm into the name of the card. Desperately, the scientist flashed card after card on the screen, and Carl called off each one correctly.
By this time the professor was so disturbed and puzzled that he had forgotten all about his appearance. Frantic fingers run through his hair had left it tousled. He tugged at his shirt collar as he walked slowly around Carl, looking at him with deep, incredulous interest.
"I just can't believe it!" he muttered.
"One-hundred-percent correct identification! Young man, can you explain how you perform this feat?"
"I just did what you told me to do," Carl said blandly. "I simply called out the card that was in my mind when the bell sounded. Guess it must be a kind of telepathy, or something."
"'Or something; is right," Professor Karns fervently agreed. "I must take you down to the university with me and give a demonstration of your phenomenal ability to my colleagues."
"Aw, I don't think I could do that," Carl objected, as he started backing toward the steps leading down from the stage. "I don't like to mess around with this sort of thing. Makes me feel kind of creepy."
"But you owe it to science!" the professor argued. "If we can repeat this experiment, my account of it will appear in every scientific journal in the world."
"I'll think about it," Carl said, hastily going down the steps.
The assembly was dismissed, and as Carl and Jerry walked along the hall Jerry whispered:
"That was a lot of fun, but it certainly means that we'll not dare wear these contraptions to school again. And' don't ever breathe a word about them. If it is ever found out how we helped ESP, you and I are going to be the guests of honor at the darndest tar-and-feathering party you ever saw; and I can just see Professor Karns ladling out the hot tar right now!"
Carl & Jerry: Their Complete Adventures is now available. "From 1954 through 1964, Popular Electronics published 119 adventures of Carl and Jerry, two teen boys with a passion for electronics and a knack for getting into and out of trouble with haywire lashups 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."
Carl & Jerry Episodes on RF Cafe
- Electronic Trap, March 1956
- Geniuses at Work, June 1956
- Eeeeelectricity!, November 1956
- Anchors Aweigh, July 1956
- Bosco Has His Day, August 1956
- The Hand of Selene, November 1960
- Feedback, May 1956
- Abetting or Not?, October 1956
- Electronic Beach Buggy, September 1956
- Extra Sensory Perception, December 1956
- Trapped in a Chimney, January 1956
- Command Performance, November 1958
- Extracurricular Education, July 1963
- Treachery of Judas, July 1961
- The Sucker, May 1963
- Stereotaped New Year, January 1963
- The Snow Machine, December 1960
- Extracurricular Education, July 1963
- Slow Motion for Quick Action, April 1963
- Sonar Sleuthing, August 1963
- TV Antennas, August 1955
- Succoring a Soroban, March 1963
- "All's Fair --", September 1963
- Operation Worm Warming, May 1961
- The Blubber Banisher, July 1959
- The Sparkling Light, May 1962
- Pure Research Rewarded, June 1962
- The Hot Dog Case, December 1954
- A New Company is Launched, October 1956
- Under the Mistletoe, December 1958
- Electronic Eraser, August 1962
- Blubber Banisher, July 1959
- "BBI", May 1959
- Ultrasonic Sound Waves, July 1955
- The River Sniffer, July 1962
- Ham Radio, April 1955
- El Torero Electronico, April 1960
- Wired Wireless, January 1962
- Electronic Shadow, September 1957
- Elementary Induction, June 1963
- He Went That-a-Way, March1959
- Electronic Detective, February 1958
- Aiding an Instinct, December 1962
- Two Detectors, February 1955
- Tussle with a Tachometer, July 1960
- Therry and the Pirates, April 1961
- The Crazy Clock Caper, October 1960
Posted March 5, 2015