| Industry | Electronics |
|---|---|
| Founded | 1910 |
| Founder | Oscar Hammarlund |
| Defunct | 1973 |
| Fate | Dissolved |
| Headquarters |  Mars Hill, North Carolina, United States |
| Products | radio equipment |
The Hammarlund Manufacturing Company was founded by Oscar Hammarlund in New York City, New York, United States in 1910. When the company was dissolved in 1973, it was among the USA's very oldest producers of radio equipment.
The first Hammarlund plant was a loft operation engaged in radio component manufacturing on Fulton Street in lower Manhattan, New York City. Their variable capacitor designs quickly became industry standards, and the component's schematic symbol was adopted as the company's logo. In the mid-1920s, Hammarlund formed a partnership called Hammarlund-Roberts Co. specifically to offer kits for AM broadcast radios using Hammarlund parts. [1] The company opened its major manufacturing facility in Mars Hill, North Carolina in 1951. [2] [3]
When Hammarlund-Roberts went out of business in 1931, Hammarlund Mfg. Co., Inc. entered into the shortwave receiver market with the introduction of the "Comet Pro", the first commercial short wave superheterodyne receiver. Professional listening post installations made great use of the Comet Pro, and it was used also on many major exploration expeditions. [4] [3]
Following introduction of the Comet-Pro came an improved receiver, called the Super-Pro (the SP-200 series). The latter was put in production in 1936. Hammarlund expanded when World War II broke out. In addition to manufacturing Super-Pro receivers (Signal Corps model BC-779), Hammarlund variable capacitor production totaled 1 million a month. [1] [3] At the end of World War II, the market was flooded with surplus receivers, which may be a reason many working examples of this model are still found today.
In 1947 the SP-600 Super-Pro receiver, which surpassed the SP-200 in performance, was introduced, covering the frequency range of 540 kHz to 54 MHz with a 0-100 calibrated mechanical band spread. The SP-600 series were widely used throughout the world for military, laboratory and commercial application. [2] [3]
While Hammarlund was most famous for its amateur/short-wave receiver lines such as the Super Pro series and the HQ series (which includes the HQ-100, 110, 120, 129, 145, 150, 160, 170, 180, 200 and 215), [5] [6] a number of transmitters were also produced. These saw only limited use. [2] [3]
Hammarlund also built a substantial quantity of the VHF FM "Village Radios" for the United States Agency for International Development (AID) to use in Vietnam, as well as a number of land-mobile radios and transceivers for the Citizens band radio market. [2]
Even as the company continued to produce communications equipment for the amateur, commercial, and Citizens Band radio markets, it underwent frequent changes of ownership. The first was in the late 1950s when Hammarlund was sold to Telechrome. Several years later Telechrome sold out to Giannini Scientific. In the late 60's the company was once again sold to the Electronic Assistance Corporation (EAC). But, this sale was final. The product line was sold off in parts or phased out. The Cardwell Condenser Corporation purchased all remaining stocks, and in 1973 the Hammarlund factory closed. At the time of its dissolution, Hammarlund was among the USA's very oldest producers of radio equipment. [2]
Today, many Hammarlund radios are collected, restored and used by vintage amateur radio enthusiasts.
There are a number of false etymologies regarding why amateur radio operators are colloquially called hams. [7] Likely an example of corporate wishful thinking, one such tale is that Hammarlund products were supposedly so pre-eminent in the pioneering era of radio that they became a part of the language of radio. As the story goes, early radio enthusiasts affectionately called Hammarlund products "Ham" products, and called themselves "Ham" operators. [8] In truth, Hammarlund was a minor and barely known company at the time "ham" started to be used.
Heathkit is the brand name of kits and other electronic products produced and marketed by the Heath Company. The products over the decades have included electronic test equipment, high fidelity home audio equipment, television receivers, amateur radio equipment, robots, electronic ignition conversion modules for early model cars with point style ignitions, and the influential Heath H-8, H-89, and H-11 hobbyist computers, which were sold in kit form for assembly by the purchaser.
Rockwell Collins was a multinational corporation headquartered in Cedar Rapids, Iowa, providing avionics and information technology systems and services to government agencies and aircraft manufacturers. It was formed when the Collins Radio Company, facing financial difficulties, was purchased by Rockwell International in 1973. In 2001, the avionics division of Rockwell International was spun off to form the current Rockwell Collins, Inc., retaining its name.
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A Hamfest is a convention of amateur radio enthusiasts, often combining a trade show, flea market, and various other activities of interest to amateur radio operators (hams). In the United Kingdom the term rally is more commonly used for amateur radio conventions. "Hamfests" were noted as early as 1924 in the U.S.
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Ham radio is a popular term for amateur radio, derived from "ham" as an informal name for an amateur radio operator. The use first appeared in the United States during the opening decade of the 20th century—for example, in 1909, Robert A. Morton reported overhearing an amateur radio transmission which included the comment: "Say, do you know the fellow who is putting up a new station out your way? I think he is a ham." However, the term did not gain widespread usage in the United States until around 1920, after which it slowly spread to other English-speaking countries.
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Vintage amateur radio is a subset of amateur radio hobby where enthusiasts collect, restore, preserve, build, and operate amateur radio equipment from bygone years, such as those using vacuum tube technology. Popular modes of operation include speaking over amplitude modulation (AM), and communicating using Morse code through continuous wave (CW) radiotelegraphy. Some enthusiasts have interest in owning, restoring and operating vintage military and commercial radio equipment such as those from 1940s to 1960s. Some undertake to construct their own gear, known in ham slang as homebrewing, using vintage parts and designs. A number of amateur radio clubs and organizations sponsor contests, events, and swap meets that cater to this specialized aspect of the hobby.
Wingrove & Rogers Ltd of Kirkby, Liverpool, England, was formed in 1919 by Major Charles William Wingrove M.C. (1889-1976) and William Rogers (b1891) to manufacture control gear for electric vehicles. In the 1920s they diversified into variable capacitors, the components essential for tuning in the front end of radio receivers which they continued through the second world war during which they supplied the armed forces. In 1926 they amalgamated with British Electric Vehicles Ltd, and moved the electric vehicle production from Southport to Liverpool where they made vehicles such as electrically motorised trolleys and electric locomotives, largely for use in factories, mines, and by tunnelling contractors.
The Hammarlund Super Pro was an American-made radio communications receiver.
The Hallicrafters SX-28 "Super Skyrider" is an American shortwave communications receiver that was produced between 1940 and 1946 that saw wide use by amateur radio, government and military services.
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