Carl & Jerry: A Light Subject
November 1954 Popular Electronics

November 1954 Popular Electronics

November 1954 Popular Electronics Cover - RF CafeTable of Contents

Wax nostalgic about and learn from the history of early electronics. See articles from Popular Electronics, published October 1954 - April 1985. All copyrights are hereby acknowledged.

Many thanks to website visitor Mr. Ferrous S. for providing an OCR version of this Carl & Jerry story, and for writing the following:

"The earliest optoelectronic devices are photodetectors, and the basis of photodetectors is the discovery and research of photoelectric effects. In 1873, Willoughby Smith discovered the photoconductivity of selenium. In 1888, German Heinrich Hertz observed that when ultraviolet light irradiated the metal, it could make the metal emit charged particles. In 1890, Philipp Lenard determined the charge−mass ratio of charged particles and proved them to be electrons, thus clarifying the essence of photoelectric effect. In 1900, German physicist Planck introduced energy quantum into the study of blackbody radiation, and proposed the famous Max Planck formula to describe the phenomenon of blackbody radiation, which laid the foundation for quantum theory. In 1929, Kohler made a silver-oxygen-cesium photocathode and a photocell resulted. In 1939, Vladimir Zvorakin of the Soviet Union made a practical photomultiplier tube. In the late 1930s, lead sulfide (PbS) infrared detectors were invented, which can detect radiation up to 3 microns. Thermoelectric infrared detectors and radiocalorimeters made of semiconductor materials appeared in the 1940s. In the mid−1950s, cadmium sulfide (CdS), cadmium selenide (CdSe), photoresistors and short-wave infrared lead sulfide photodetectors were put into use. In 1954, the first silicon-based solar cell was born at Bell Laboratory in the United States. In 1958, HgCdTe infrared detector was invented by William Lawson et al."

Carl & Jerry: A Light Subject

Carl & Jerry: A Light Subject, November 1954 Popular Electronics - RF CafeBy John T. Frye, W9EGV

Carl Anderson entered his home in his usual forceful manner. That is, he took a giant step across the threshold and clung tightly to the doorknob until the slamming door stopped him in mid-stride. He next dog-trotted down the hall to the open door of the living room where he stopped briefly to execute a graceful push- shot with his schoolbooks to the davenport cushions. Finally he sailed into the kitchen like a whirling dervish. With almost a continuous motion he jerked open the refrigerator door, lifted out a pint bottle of chocolate milk, downed it with four or five thirsty gulps, and banged the door shut. The empty bottle went into the sink with a jangling clatter as the boy slammed out the back door. Upstairs in her sewing room Mrs. Anderson listened to the progress of this miniature door-slamming tornado through the downstairs part of her house without any particular sign of annoyance. In the first place, she was used to it; and in the second, she experienced that warm feeling of contentment a mother always knows when her children, be they four or forty years of age, are safely home. Even though Carl had gone out the back door she knew he was headed no farther than the basement "laboratory" of his friend, Jerry Bishop, next door.

As Carl skipped down the outside basement steps and burst through the door, his eyes were met by a singular sight. Jerry's well-padded form was sprawled on the couch at one side of the room. Although it was still broad daylight, he held a lighted flashlight in his hand and was waving the narrow beam languidly back and forth across the face of what looked like a small birdhouse sitting on the workbench along the opposite wall. Each time the spot of light passed over the quarter-sized opening in the face of this box, an electric bell lying on the bench beside it gave out with a brief "br-r-r-ing" of sound.

Carl & Jerry: A Light Subject - RF CafeCarl slumped against the doorjamb and said lugubriously, "I've been afraid of this. The mad genius has finally flipped his lid. That's what comes of reading physics texts and tube manuals instead of comic books like any other red-blooded American boy. I'm a little disappointed, though, in the lack of originality. Old Diogenes used that carrying-a-light-in-the-daytime routine several centuries ago."

"That's our boy!" Jerry murmured as he grinned across at Carl. "If you can't understand it, belittle it, is the motto, huh? Had you not been so busy trying to lash your feeble intellect into thinking up a wisecrack about the flashlight, you might have noticed some connection between my moving its beam back and forth and the ringing of the bell."

"So-o-o-o," Carl drawled with quizzically arched eyebrows.

"So I'm experimenting with photoelectric cells. Notice that as long as I keep the beam of light on the cell through that small opening in the box the bell continues to ring, but it stops as soon as the light is turned away."

"Say, how about that! That's pretty neat!" Carl said with sudden enthusiasm. "Let me do it. How does it work?" he asked as Jerry let him take the flashlight and play it back and forth across the opening in the box.

"You really want to know or are you just asking to be polite?" Jerry demanded.

"I really want to know, Stupid!" Carl growled, "and you're just aching to lecture; so quit stalling and get on with it."

"Okay, but first I've got to know if you remember anything at all of what you learned in physics about the construction of an atom."

"Of course I remember," Carl said indignantly. "An atom has a positive nucleus about which circle tiny negative do-jiggers of electricity called electrons. There are always just enough of these electrons in a normal atom so that their total negative charge is equal to the positive charge of the nucleus, leaving the atom with a neutral charge. Under some circumstances, though, an electron can be pried loose from its atom and go bucketing around by itself. An atom that has lost an electron assumes a positive charge and is called an ion. Electrons are attracted to any positively charged object; ions have a yen for negatively charged things."

"You amaze me!" Jerry remarked as he lifted up the lid of the box on the bench and pulled out a small glass photoelectric cell. "You can see this cell only has two elements in it. That half-cylinder is the cathode, and the little rod in the middle is the anode. Notice the inside surface of the semi-cylinder is coated with a kind of silvery-colored gunk. The stuff may be one of several different substances, but whatever one is used in this particular tube, its main characteristic is that electrons are given off from its surface whenever light falls upon it. Up to a certain point, the more light that falls on this cathode coating the more electrons are emitted."

"What's inside the bulb besides the cathode and anode?"

"Mostly plenty of nothing. Maintaining a high vacuum inside the bulb greatly aids the emission of electrons from the cathode and helps them cross over to the anode."

"Why do they go to the anode?"

"Because it is positively charged with respect to the cathode. You will remember you told me a positively-charged object has a great attraction for free electrons. In this case the anode is ninety volts positive with respect to the cathode, and there is a steady stream of electrons from the cathode to the anode. Any time you have a stream of electrons all moving in the same direction you have an electrical current, for an electric current is made up of a movement of electrons. Before I forget it, I had better mention that while this particular tube is of the high vacuum type, some photoelectric cells have a controlled amount of gas inside the bulb."

"What's the idea?"

"It increases the sensitivity. Let me think how I can explain this. Oh yes, now I've got it. Did you ever see an apple fall from the very tiptop of a tree heavily loaded with dead-ripe fruit?"

"Suppose I have, but what's that got to do with photocells?"

"Perhaps you noticed that on the way down the falling apple struck other apples and dislodged them so they fell with it. The branches on which these apples had been clinging jerked upward as they were freed of the weight of the dislodged fruit, and this movement knocked loose still more apples from the branches above them. The net result could easily be a dozen apples falling to the ground as the result of the loosening of that first apple from its stem.

"The same thing happens inside the gas type photoelectric cell. As an electron is scampering merrily along toward the anode, it collides with a gas atom and knocks loose one or more electrons from the atom that immediately join it on its short and speedy journey. The gas atom, converted into an ion by the loss of an electron, is attracted to the cathode. As it falls into the cathode the smash knocks loose still more electrons that are then free to go to the anode. Just as happened with the apples, for every electron that is freed from the cathode by the influence of light falling upon it, a half-dozen or so electrons may reach the anode. This greatly increases the sensitivity of the cell."

"Then why aren't all photoelectric cells of the gas type?"

"A shrewd question, Carlos mi amigo, but there is an answer: while gas cells have a higher sensitivity than vacuum types, the latter have higher internal resistance, maintain a more constant sensitivity throughout their life, and are not so easily damaged by applying higher than rated voltages." "How come you've got other parts in this box? I see another tube in here besides a relay and a bunch of resistors. Why don't you just put the relay that turns the bell on and off in the anode circuit of the photoelectric cell and let the current flowing through the cell open and close it?"

"Because the current through the cell is very tiny, being measured in microamperes. A relay that would work on such a tiny current would be very delicate and undependable. It is much better to employ some sort of current amplifying tube between the cell and the relay. That tube you see in there is one particularly suited for this job and is called a thyratron."

"What the heck's a thyratron? Sounds like a glandular disease."

"Well, it's not. A thyratron is sometimes called a relay tube because its action is very much like that of a relay. As long as the negative potential on the grid of such a tube remains above a certain critical value, no current at all flows through the plate circuit of the tube; but when the negative grid voltage is lowered to that critical value, the plate current suddenly rises from zero to a comparatively high value. If we adjust the grid voltage of a thyratron very close to the critical value and then arrange for the current through our photoelectric cell to influence this grid potential, very slight changes in illumination of the cell can produce rapid and positive operation of a relay in the plate circuit of the thyratron tube. Photoelectric cells and thyratrons go together like hot dogs and root beer."

"Are there any other kinds of photoelectric cells besides the vacuum and gas types?"

"Sure thing. Both of these are what are known as 'emissive' types. In addition we have the 'conductive' type of cell. This cell has two electrodes connected by a material that exhibits a change in resistance in accordance with the light falling on it. A typical cell will display 30 megohms of resistance in the dark and only one megohm in bright sunlight. Such a cell behaves much the same as the emissive type with this exception: it displays no polarity and is less subject to damage by high voltages. Conductive cells may or may not be mounted in a vacuum, for low pressure is not necessary for their proper action."

"What kind of a cell is in the light meter my dad uses in taking pictures?"

"That's still another type called the 'generative' cell. In many ways, particularly at this time, it is the most interesting of the lot. Several materials, including selenium, cesium, and metal sulphides, are capable of generating an electrical current when light energy falls on their surfaces. Selenium compounds and selenium sulphide output small but predictable amounts of current. Several cells with a combined known amount of surface area are connected together so that the meter reading indicates the footcandles of light falling on the cell window."

"Why do you say these cells are the most interesting 'particularly at this time'?"

"For one thing these cells convert light energy directly into electrical energy without first going through some other form, such as heat. That has tremendous and exciting significance. Every single day the sun bathes the earth in more than 1,000,000,000,000,000 kilowatt hours of energy. This daily gift of radiated energy is equal to all that is contained in the world's reserves of coal, oil, natural gas, and uranium. The sad part of it is, though, that practically all of this energy goes to waste, at least as far as man's attempt to harness it is concerned. Your dad's photoelectric exposure meter represents about the best we have been able to do in converting light into electricity until very recently. and it has an efficiency of only about one per-cent.

"Just a few months ago, however, the Bell Laboratories that invented the transistor, came up with a new solar energy converter that is six times as efficient as the light meter. Each cell in this converter is made up of a wafer of two types of specially treated silicon—the main ingredient of common sand. One of these silicon cells in full sunlight will produce about a half a volt with no load. When the load is adjusted to take maximum power, the voltage falls to about one-third of a volt and stays close to that figure over a wide range of illumination. A short- circuited cell in bright sunlight will deliver about one-eighth of an ampere for each square inch of active surface or about one-tenth ampere at a load causing a one- third volt output. Groups of cells can he connected in parallel for additional current or in series for additional voltage. As long as this 'solar' battery is working into a high impedance load, good voltage output is had with much less than full illumination. On quite cloudy days the silicon cell will produce usable output with the radiation that comes from the sky."

"How much power have they managed to get out of thing?"

"Silicon solar batteries have been used to power transistorized radios and transmitters and to operate a toy ferris wheel. Telephone engineers are already thinking about using them to run low-power mobile equipment or as battery chargers for amplifiers in rural telephone systems. At present it. takes a ten-cell battery to produce 1 quarter of a watt, and Bell engineers estimate you would need about twenty five square feet of silicon wafer to keep a hundred-watt lamp burning and about a quarter of an acre of the stuff to power a small home.

"Keep in mind, though, that we have just got a toe-hold in this field, and improved efficiencies are bound to appear. In fact the Wright Air Development Center of the Air Research and Development Command has already announced a new solar generator using cadmium sulphide instead of silicon, and it has been estimated that a thin crystal slab of this material with an area of only sixty square feet could be built into the roof of a house and would supply all its electrical requirements."

Carl stood up and stretched until his joints cracked. "That's the way it goes," he mourned. "No longer will I be able to draw a simple pleasure from watching the electric eye door at the super market swing open at my approach. Now I'll be thinking about thyratrons, electrons, silicon cells, and cadmium sulphide. Worse yet, when I'm trying to get a sun tan, I'll be feeling guilty about all that solar energy I'm squandering!"

 

 

Posted May 25, 2021
(updated from original post on 2/5/2014)

Carl & Jerry Episodes on RF Cafe

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.

 - See Full List - 

Carl & Jerry, by John T. Frye - RF CafeCarl & 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 electronic equipment.

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.

Carl & Jerry Their Complete Adventures from Popular Electronics: 5 Volume Set - RF CafeCarl & 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."