The Vanishing Circuit Designer

How is this for a prescient prediction from the early 1960s? "As a result of modular and integrated circuitry techniques, all future circuit design work, regardless of degree, will become the responsibility of the component manufacturer instead of the equipment producer." Texas Instruments' (TI) Jack Kilby is credited with designing the first integrated circuit in 1958. The first commercial IC, Ti's Type 502 flip-flop, had just hit the market in early 1960, and already pundits were prognosticating and ruing the disappearance of circuit designers. Maybe it was concerns over job security that they seem to favor forever building every circuit from discrete transistors, resistors, capacitors, and inductors. Rumor has it they also lobbied for the perpetual existence of the buggy whip and horse-drawn farrow industries...

Heat Without Flame

Electric induction heating has been used in manufacturing processes since shortly after Benjamin Franklin invented electricity. Of course I jest about Franklin; he didn't invent electricity but discovered that lightning was a form of electrical discharge. One of the most energy-consuming forms of induction heating is that used by Alcoa for smelting aluminum. Beyond that are many thousands of processes ranging from forming, tempering, and joining metal parts to cooking food and curing adhesives. Both Tocco and Ajax-Northrup, now Ajax Tocco, brands of equipment are featured in this 1955 article which appeared in Popular Electronics magazine. Some processes work by directly inducing a high current in the primary target object - usually metallic - being treated...

An Avocation Becomes a Vocation

Did you know that the Hallicrafters line of radios is named after founder Bill Halligan (W9WZE)? Hallicrafters, founded in 1932, was a major manufacturer of amateur radio gear. During the years of WWII they ruggedized some of their products to survive the harsh environments of battle. Hallicrafters was sold to Northrop Corporation in 1966, at which time the product line essentially ceased. Their gear is still very collectible by aficionados of vintage Ham equipment. This story from the February 1943 QST provided an inside look at the production floor at Hallicrafters. Having cut my figurative electronics teeth on radar and radio equipment built with tubes and point-to-point wiring while in the USAF, and then later as an assembly/test technician at Westinghouse Electric building sonar equipment...

Osgood Lens Advertisement

Finding information on the Osgood Lens, invented by James R. Cravath, is challenging. For as prominent as it was in magazines like The Saturday Evening Post in the late 1910s and 1920s, there is not even a Wikipedia entry for the lens type or the man according to my searches. Although not exactly the same as the Fresnel lenses used by lighthouses since the 18th century, the concept is basically the same. Of course the Osgood company was careful not to use the term Fresnel in their literature for potential patent infringement reasons. Some vehicles might have been fitted with them as a factory installed option, but they were also sold as add-on items. According to the literature the tiered stack of prism-shaped glass directed the headlight beam toward the road...

Down-to-Earth Discussion - Resistance of a Ground

For some reason the subject of grounding has been very prominent in my reading in the last few days. The chapter I just finished reading in one of David Herres' books on the National Electric Code (NEC) covering grounding of commercial and residential services, an article by H. Ward Silver in QST titled, "Grounding and Bonding Systems," and now this article by John T. Frye (of Carl and Jerry fame) on grounding, makes for a wealth of knowledge. Mr. Frye takes a unique approach at teaching by exploiting his gift for story-telling. In this article, electronics repair shop owner Mac gives technician Barney a nice bit of tutelage on what constitutes a good Earth ground and what does not. In some environments, treating the soil with an electrically conductive substance is necessary to establish a suitable ground without having to drive...

After Class: Resistor and Capacitor Combinations 

Here is a short tutorial on resistor-capacitor (R-C) combinations and the time constants created by their combinations. It's pretty basic stuff, but there are new people coming into the field of electronics all the time so it is worth posting. Discussed are coupling circuits, filter networks, differentiators, and time-delay circuits. The "After Class" feature is a series run by Popular Electronics magazine in the 1950s and 1960s. As with this installment, "After Class" presented topics on electricity and magnetism that served not just as new material for beginners, but was a good review even for seasoned practitioners of the craft...

The Amana Radarange

As legend goes, the use of microwaves for preparing food was pursued after a serendipitous discovery by Raytheon engineer Percy Spencer whereby he noticed the chocolate bar in his pocket had melted while he was working near a radar transmitter magnetron. Being a newly discovered phenomenon in 1945, Mr. Spencer was probably not aware that his own body parts were being likewise cooked, but he did recognize the commercial potential of an oven that used microwaves to cook food. It only took Raytheon (Amana) to have the first Radarange available for sale to professional kitchens. This article was printed a full decade after the discovery and even then the size and power consumption was too great for grandma's countertop...

Carl & Jerry: TV Picture

Television, in 1955, was still a relatively new phenomenon to many - maybe even most - people. According to multiple sources, the portion of American households with a TV set went from under 20% in 1950 to nearly 90% ten years later in 1960. That was a meteoric rise, particularly considering the expense of even a minimal TV. The technology was not even available commercially when most people were born, so the rush to join in on the craze was akin to the mass adoption of cellphones in the 1990s. "Carl & Jerry" creator John Frye used his pair of electronics-savvy teenagers to help make the "magic" behind recreating a moving picture on a cathode ray tube (CRT) miles away from where it was created. Water flowing through a garden hose has often been employed as an analogy for current...

Harold Beverage of the Eponymously Named Antenna Type

The Beverage Antenna, very familiar to amateur radio operators, is a simple but efficient, highly directional, non-resonant antenna that consists of a single straight wire of one or more wavelengths that is suspended above the ground. It is orientated parallel to the direction of intended reception. One end is terminated to ground through a resistor, and the other is connected to the receiver. The following quote comes from the patent (US1,81,089) text: "In accordance with theoretical considerations, if an antenna were to be freely suspended and if the surface of the earth constituted a perfectly conducting parallel plane, current waves would travel through the antenna conductor at a velocity equal to the velocity of light...

Amateur Radio - CW Is Dead (?)

It's funny how often topics crop up bemoaning the current state of society, technology, etc., as if they are suddenly new plagues upon the entities concerned. That's not to say the subjects are not worthy of being brought to the forefront of public awareness, but often times in fact those same issues are exactly the same or reincarnations of former "emergencies" in need of immediate attention. I have posted numerous articles and editorials from vintage electronics and hobby magazines lamenting the poor state of youth involvement, with blame being laid in the lap of some newfangled hobby or activity that is presently stealing away erstwhile brethren. The effort is usually not in vain since the intended effect of motivating fellow enthusiasts to reinvigorate and motivate those drifting prodigals...

Engineering & Science Crossword Puzzle for April 21

Since 2000, I have been creating custom technology-themed crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you...

Notes on the Getter

If you happen to be Estonian, you might think of something entirely different than most of us do when we hear the word "getter." In fact, you probably capitalize the word since it is the name of a pop singer from your country, Getter Jaani. If you are a child living in Japan, you would probably think of Getter Robo, an anime from a popular cartoon series. I, and I dare say just about everyone else that visits RF Cafe, knows getter as that silvery deposit (typically barium) that resides inside vacuum tubes for the purpose of helping to maintain the vacuum and to absorb pesky random molecules that might otherwise cause electrical noise in the circuit. This article from a 1958 edition of Radio-Electronics discusses the purpose of getter. BTW, I had never heard of either of the other two Getters due to OGS (old guy syndrome)...

AC Motor Basics

Chapter 16 of the "Electricity - Basic Navy Training Courses" introduces concepts of alternating current (AC) motors, their electric supply, and controls. It is part of the NAVPERS (Navy Personnel) 10622 series which is highly regarded both in and out of the military. The manuals were first written in the middle of the last century and have been upgraded a few times since then, but if you compare the sections this one on AC motors in both the original and most modern versions, not much - if anything - has changed. If you have an interest in motors and want to understand the basics of how they work both as motors and generators (AC and DC), then there is not a much better source from which to start...

Air Traffic Control by Electronics

Air Route Traffic Control Centers, now using the acronym ARTCC rather than ARTC as used in this 1960 article, were and still are the human and computer command and control facilities responsible for safe and orderly flow of air traffic in the U.S., and a worldwide network of Area Control Center (ACC) handles everything else in a massive coordinated effort. The advent of radar during World War II and the ensuing evolution of it and electronic computers in the following years struggled to keep pace with the equally rapidly evolving aircraft design and capability. A simple control tower with air traffic controllers using binoculars and a radio mike could not handle the volume of airplanes and helicopters traversing the skies and patronizing busy terminals. Many forms of electronic navigation aids were developed including very high frequency omnidirectional range (VOR), direction finders (DF) using antenna nulling for finding radials to/from FM radio transmitter, long range navigation (LORAN)...

DC Motors & Generators

Studies of motors usually begin with the direct current (DC) type - maybe because most students have already had hands-on experiences with motors in models (cars, boats, airplanes) and/or electricity experimenter kits. They are small, cheap, and a simple flashlight battery (the ultimate in safety) makes them run. An alternating current (AC) motor requires either a direct connection to the house current or use of a step-down transformer, which still carries with it a high risk factor. This chapter of the U.S. military's Basic Navy Training Course (NAVPERS 10622) conforms to the tradition, and follows in the next chapter with AC motors and generators. While reading through the text, I ran across the unfamiliar term "kickpipe" and wondered...