The Hammarlund Manufacturing Company was founded by Oscar Hammarlund in

New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the Un ...

, New York, United States in 1910. When the company was dissolved in 1973, it was among the USA's very oldest producers of

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmi ...

equipment.

History

The first Hammarlund plant was a loft operation engaged in radio component manufacturing on Fulton Street in lower

Manhattan Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the original counties of the U.S. state ...

, New York City. Their

variable capacitor A variable capacitor is a capacitor whose capacitance may be intentionally and repeatedly changed mechanically or electronically. Variable capacitors are often used in L/C circuits to set the resonance frequency, e.g. to tune a radio (therefo ...

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. The company opened its major manufacturing facility in

Mars Hill, North Carolina Mars Hill is a town in Madison County, North Carolina, United States. The population was 1,869 at the 2010 U.S. Census, and was estimated at 2,032 in 2018 by the U.S. Census. It is the home of Mars Hill University, the name of which was inspired b ...

in 1951.

Comet pro receiver

When Hammarlund-Roberts went out of business in 1931, Hammarlund Mfg. Co., Inc. entered into the

shortwave receiver A shortwave radio receiver is a radio receiver that can receive one or more shortwave bands, between 1.6 and 30 MHz. A shortwave radio receiver often receives other broadcast bands, such as FM radio, Longwave and Mediumwave. Shortwave radio recei ...

market with the introduction of the "Comet Pro", the first commercial short wave

superheterodyne A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carri ...

receiver. Professional listening post installations made great use of the Comet Pro, and it was used also on many major exploration expeditions.

Super pro receivers

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 World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

broke out. In addition to manufacturing Super-Pro receivers (Signal Corps model BC-779), Hammarlund variable capacitor production totaled 1 million a month.Jerome S. Berg.
On the Short Waves, 1923-1945: Broadcast Listening in the Pioneer Days of Radio
'. McFarland; 1 March 1999. . p. 241–, p. 184–. 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 The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that on ...

to 54

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

with a 0-100 calibrated mechanical band spread. The SP-600 series were widely used throughout the world for military, laboratory and commercial application.

Communications gear

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), a number of transmitters were also produced. These saw only limited use. Hammarlund also built a substantial quantity of the VHF FM "Village Radios" for the

United States Agency for International Development The United States Agency for International Development (USAID) is an independent agency of the U.S. federal government that is primarily responsible for administering civilian foreign aid and development assistance. With a budget of over $27 b ...

(AID) to use in

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

, as well as a number of land-mobile radios and transceivers for the

Citizens band Citizens band radio (also known as CB radio), used in many countries, is a land mobile radio system, a system allowing short-distance person-to-many persons bidirectional voice communication among individuals, using two way radios operating on ...

radio market.

Final decades

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. Today, many Hammarlund radios are collected, restored and used by

vintage amateur radio 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 spe ...

enthusiasts.

Hammarlund legend

There are a number of false etymologies regarding why amateur radio operators are colloquially called

hams Ham is pork from a leg cut that has been preserved by wet or dry curing, with or without smoking."Bacon: Bacon and Ham Curing" in ''Chambers's Encyclopædia''. London: George Newnes, 1961, Vol. 2, p. 39. As a processed meat, the term "ham ...

. 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. In truth, Hammarlund was a minor and barely known company at the time "ham" started to be used.

References

External links

{{Commons category
Cardwell Condenser Corporation (Current holder of Hammarlund Parts Stocks)

Hammarlund rigs

Hammarlund collection from N9SOR
Electronics companies established in 1910 Amateur radio companies 1910 establishments in New York City Electronics companies disestablished in 1973 1973 disestablishments in North Carolina Defunct manufacturing companies based in New York City Defunct manufacturing companies based in North Carolina