This history of Microwave Journal as told through the articles that appeared in the magazine over the past 50 years is also the history of the microwave industry as told by those in the business. This series looks at the past five decades of microwave technology as described in the nearly 600 issues of Microwave Journal published since its founding. In this second installment of our six-part series, we look at the transformative decade of the 1960s where engineers went from crew cuts to sideburns and the microwave industry found opportunities in long haul telecommunication applications along with the ongoing needs of the defense department as the Cold War heated up. This will be the decade for new interest in millimeter-waves and the emergence of microwave integrated circuits as the next big thing.
THE 1960S
January 1960: It’s a new decade and a forward looking article called “Millimeters—The New Frontier” is written by guest contributors Archie Straiton and Charles Tolbert (see the full reprint in this month’s “Then” cover feature). In this article, the authors consider the “scariest commodities in this country today is space in the radio spectrum. With an increase in broadcasting services, public and private communications, aircraft guidance, military applications and thousands of other uses of the radio spectrum, demand for available frequencies will far exceed the supply.” This overpopulation of the radio spectrum had the authors reporting on the increasing interest in the vast available bandwidth at millimeter-wave frequencies. The authors then discuss the unique characteristics of millimeter radio waves as well as the challenges of using these frequencies.
While Evans Nalos of General Electric Co. Microwave Laboratory, Palo Alto, CA, looks at the “Present State of the Art in High Power Travelling-wave Tubes” (the Journal cover features a picture of GE’s high power metal-ceramic TWTA; see Figure 1), the solid-state conference program for the 1960 International Solid-Sate Circuit Conference held at the University of Pennsylvania is printed in its entirety. Papers presented cover new magnetic and semiconductor devices and circuits for digital storage and logic. Also presented are surveys on tunnel diodes, thin magnetic films and the microwave properties of semiconductors.
February 1960: Editor Ted Saad explains the editorial review process to Journal readers. At the time, each paper receives at least two comprehensive reviews by members of the review board. These independent reviews are then considered by the editorial staff in deciding if the article is accepted for publication, requires modification or will be declined. At the end of his editorial, Saad congratulates Dr. Ben Lax, who as associate editor was one of the individuals responsible for the editorial review process and who was awarded the 1960 Oliver E. Buckley Solid-State Physics prize. This editorial review process is still in effect today, with a new cast of distinguished technologists reading each submitted article. On all published technical articles, readers will see the familiar Microwave Journal Editorial Board Reviewed seal—our mark of quality.
March & April 1960: The tale of two shows: Editor Ted Saad makes a convincing argument in his editorial on the merits of attending the National IRE Convention in New York and Microwave Journal dedicates its cover to the 1960 PGMTT National Symposium in San Diego, CA, a tradition that continues to this day. In Saad’s editorial, he notes the concerns of many in the industry that the National IRE convention is “big, it is commercial, it is noisy, and it does not have the technical stature that the Professional Group Symposiums have,” while addressing the merits of this event that “draws hundreds of manufacturers and thousands of engineers. For four days and more, engineers can pick brains, study new products, hear technical papers and socialize.” The commercial involvement in the MTT symposium is still years away, but in 1960 Saad nails it with his statement that a convention is “a time to exchange ideas, to talk with the experts to find out what is new” and that a conference with a strong commercial component (i.e., exhibition) is “technical, economic and social. To consider one as divorced from the others is a misrepresentation of the facts.”
January 1962: Microwave Journal continues its international editorial coverage with French and German translations of technical feature abstracts. One factor for these multi-lingual abstracts was the steady growth in the Journal’s foreign circulation. Another factor that actually started the idea was the number of foreign language publications that the editors were receiving and how they were favorably impressed by those that had been translated into multiple languages. While the entire paper would not appear translated in print, the editors felt that “the abstracts along with the many curves, tables and equations typical to most technical articles would give the reader a substantial amount of information about any technical paper.” Publishing the technical abstracts in three languages would continue monthly until the December 1965 issue when the magazine announced the launching of an international edition starting the following month. The North American edition would be mailed to a circulation of 29,000 in the United States and Canada; the European-Asian edition would be mailed to 8000 in Europe, Asia, South and Central America, Australia and Africa.
January 1966: The cover story (see Figure 2) this month was called “An Industry Report—Microwave Components or Microwave Circuits.” The Industry Report cover stories began the year before and would morph into the dedicated issue themes that are still part of Microwave Journal today. These themes reflect the continuing maturation of the industry into distinct areas of interest, technical discipline and business concerns. As is true today, Microwave Journal editors would solicit experts for cover stories discussing the state of the art.
For January 1966, the editors approached circuit expert Wesley Matthaei. Matthaei described the “state of the art” in which “the microwave component industry has evolved its concept of a microwave component to one which includes one or more circuit elements or one or more circuit functions.” The author goes on to discuss how the “advent of improved solid state device and technology are addressing the requirements of lower costs, improved reliability, and smaller sizes and weights.” The author proposed addressing circuit integration by one of two “new” approaches. The first assimilates two or more components into a microwave package or module (Matthaei mentions that the term “integrated circuit” in solid state electronics had been preempted by the computer component manufacturers to mean monolithic circuit, i.e., the construction of circuits on or in a single substrate). The second approach based on a “microwave integrated circuit” combines two or more components using a single substrate. Examples of microwave solid state technology at the time included: Gallium Arsenide varactors with frequency cutoffs in the 250 to 350 GHz range, Schottky barrier mixer diodes commercially available from L- to Ku-band, microwave transistors “now available” as microwave amplifiers (or oscillators), L-band transistors with noise figures of 3.5 dB and S-band transistors with 5.5 dB noise figure (in limited production).
In this issue, Seymour Cohn authors a tongue-in-cheek article entitled “Microwave Components are Fun.” In it, he would take time to consider the psychology of the individual microwave component designer. He describes a typical microwave engineer as one who “wakes early in the morning with his mind already sifting and analyzing thoughts of hybrid junctions and isolators. He bolts his breakfast while skillfully skimming the newspaper’s headlines and comic strips for new microwave ideas. He drives to work noting the highway’s close resemblance to a waveguide, the wave-motion nature of traffic congestion, and the analogy between voltage breakdown and multiple collisions.” Cohn continues by stating that microwave components are fun because “their design allows a wide range of invention and creative enjoyment. Because their performance is closely predictable in term of basic mathematical principles, and surprisingly unpredictable when mathematical principles are misapplied.” In well designed components, the editor sees structural beauty for those with an eye that appreciates geometrical simplicity and functional elegance.
Editor-in-Chief Ted Saad wrote about microwave components from a market perspective, suggesting that manufacturers give serious attention to broadening their markets, particularly in the area of commercial, industrial and consumer applications. Saad points out that while most microwave component manufacturers have developed parts to meet stringent specifications that perform with very high reliability under adverse environments at a reasonable price, they have experienced little serious competition and that their production quantities are quite low (in the tens or hundreds). He considers these factors have led to components that are over-designed, too expensive and ill-prepared for high volume commercial markets.
Publisher Bill Bazzy also addressed this theme in his editorial called “A Two Pronged Attack.” Bazzy described the magazine’s charter to communicate the broader business landscape affecting the health of the industry so that the many companies pre-occupied with their immediate “crash” programs could engage in longer term planning. Bazzy used specific examples highlighting the ups and downs of the microwave business since the start of the magazine, a microwave market still in its infancy serving mostly the military in 1957, the rapid success of numerous small businesses, an emerging commercial segment, followed by a leveling off of growth due to an electronic recession in late 1963 and 1964, and a strong microwave index heading into 1966. His principal concern at this time was the critical shortage of student engineers, first noted in a 1960 editorial. Bazzy and others felt that the current scramble for trained personnel threatened to result in soaring costs and dropping productivity. To address these concerns, Bazzy re-dedicated the magazine to providing the industry with the analysis necessary to see beyond the immediate future. In the publisher’s words, “We plan to solicit attitudes, concepts and courses of action from the many firms in our industry on plans for progress as well as problems of microwave business.” Bazzy then wrapped up this issue on the state of the art for microwave components discussing specific opportunities in the military and industrial markets.
Also of note this month is an article entitled “Dielectrically Loaded Stripline at 18 GHz” by a young engineer from the LEL Division of Varian Associates on Long Island, NY, named Harlan G. Howe, Jr. (see Figure 3). A graduate from the University of Rochester in 1957, Howe is a product group leader responsible for the development of stripline components at LEL and a member of the IEEE and G-MTT. In addition to his many contributions to advancing stripline technology, Howe will play a significant role at Microwave Journal some years ahead.
January 1967: The start of Microwave Journal’s ninth year in publishing and judging by the “groovy” artwork adorning the cover of the magazine, the Summer of Love can’t be too far away (see Figure 4). This colorful and expressive style will last for a couple of years when the abstract designs will become more representational of microwave hardware (hand drawn). In this issue, the attention is focused on microwave components with contributions from Dr. Seymour Cohn on “Microwave Components—1967,” Dr. John Pippin of Scientific-Atlantic on “Enter the Interface” and Bill Bourke of Narda Microwave Corp. looking at the business of microwave components. Editor-in-Chief Ted Saad ties the separate articles together by noting that all three discuss the “many exciting challenges for component people to face” and that “the areas that will receive serious attention in the immediate future” include miniaturization, broader bandwidth and “the combination of several components or several functions into a single microwave circuit.” This is a familiar challenge some 40 years later. Both William Bourke of Narda Microwave and Microwave Journal publisher William Bazzy write about the microwave business itself in this issue. Both are optimistic about the near future and both consider healthy company backlogs as an indicator of a vibrant economy for the industry. Bazzy looks at the ongoing engineering shortage first discussed the previous January and a rather flat stock index for the industry with some concern as Bourke challenges the industry to not rest on the laurels of back orders and busy employees. Bourke also challenges other companies to anticipate their customer’s future “measurement” needs and to work toward goals, which will make their customers more efficient and profitable.
January 1968: A shift in microwave technology is noted in an editorial by Richard Walker, VP and assistant to the president of Microwave Associates. In his article, “The Waveguide Component,” Walker presents his review of microwave technical literature and meeting programs and notes a decreasing emphasis on waveguide components and a growing interest in microwave integrated circuits (MIC). The benefits include smaller size, lower weight and better quality and reliability. The author believes these factors will help push the adoption of MIC technology in radar equipment, electronic counter measures and communication equipment. The accuracy of Walker’s predictions is made evident in the following months with growing editorial based on MIC, such as February’s “Microwave Integrated Electronics for Radar and Communication Systems” article by T.M. Hyltin of Texas Instruments. In no time, pictures of RF boards and IC layouts will be regular images in technical articles.
December 1969: The final issue of the decade (see Figure 5) includes an editorial by Saad discussing “The Year of Discontinuity,” brought on by the rapid changes in technology (and the challenges in keeping up), the discontinuity in government spending (a shift from manufacturing to R&D), a discontinuity in applications (the search for non-government funded sources of revenue) and the ongoing changeover from a component industry to a circuit (or sub-system) industry. Executive Editor William Peyser adds his two cents in an opinion piece entitled “The Winds of Change,” in which he summarizes the issue of the day for many microwave companies when he writes, “The question for microwave companies is no longer whether to go into MICs, but rather what schedule to follow in phasing from one technique to the other. Today’s outstanding products are tomorrow’s buggy whips. Find out what is brewing and sample it. It may be heady stuff, but it is the elixir of success.”
CONCLUSION
The decade started with a call for the industry to look at millimeter-waves in order to address the crowded radio frequency spectrum and ended with significant developments in microwave semiconductors and the rapid adoption of MIC technology in most of the microwave applications being pursued at the time. The decade that started with Americans behind the Soviets in the space race ended with the Apollo mission’s successful landing on the moon. Our industry’s contribution to this incredible milestone is captured in a December 1969 article called “S-band Antenna Measurements for Manned Flight on the Apollo Program” by J.F. Linsey III and Louis Leopold of the NASA manned Spacecraft Center. The article describes a ground-reflection range developed by the University of Michigan to emulate the patterns of the S-band omni-directional antenna system for the various spacecraft configurations (command, service and lunar modules) (see Figure 6). Due to size and weight, pattern measurements from a full-scale model were not feasible. In a way, the final editorial of 1969 and this NASA article sum up the 1960 microwave decade perfectly. The past ten years had brought unimaginable advances, growth and prosperity despite considerable uncertainty. The industry was finding broader markets, more stabilized funding and the technology was evolving from one-of-a-kind microwave components to higher quantity integrated circuitry.