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History of the manufacturer  

Amrad Corporation; Medford Hillside (MA)

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Name: Amrad Corporation; Medford Hillside (MA)    (USA)  
alternative name:
American Radio & Research
Abbreviation: amrad
Products: Model types Tube manufacturer

Amrad Corporation
205 College Avenue, Medford Hillside, MA

Amrad is the short name for American Radio & Research Corporation.
Also manufacturer of the Amrad "S" Tube, a Vacuum Tube without Filament.

Founded: 1915
Closed: 1925
Production: 1915 - 1928

Amrad is short name for American Radio & Research Corporation, Medford Hillside, Massachusetts. According to "Radio Collector's Guide 1921-1932" by Morgan E. McMahon, page 25, Amrad was aquired by Crosley Radio Corp. in 1928. The Amrad company was founded in 1915 with funds  supplied by the financier J. Pierpont Morgan. His organization had offices in New York City and had helped other major US companies. The first manager of Amrad was Harold James (Jimmy) Power and he had obtained his amateur radio transmitters license as early as 1907. He built a reaearch laboratory and in March of 1916 was able to broadcast phonograph records and a three hour program to J Porgan Jnr, who was at the time on board the ocean liner "Philadelphia" which was off the coast of Cape Cod.

In June 1916 the US Signal Corps ordered eight so called "cart sets" which consisted of a radio transmitter and receiver powered by a petrol driven generator. This was all mounted on a wheeled field gun carriage (minus the gun). These sets were quite large and were made at a factory in New Jersey. Other orders were received from the US military and in early in may 1919 the Signal Corps ordered several thousand SCR74A trench transmitters and the factory at Tufts was expanded with an additional floor to meet this order. At the end of the War the Government discontinued their orders.  

In the following years Amrad manufactured such things as electric egg beaters and cigar lighters to keep in business. In 1919 they were awarded a contract to make four hundred SE1420 receivers and by October of that year were able to advertise some components for amateur radio enthusiasts. In August 1921 almost a quarter of a much bigger factory had been completed and this was to eventually cover two hundred thousand square feet. About this time the company began making the Amrad "S" gaseous rectifier tube. Also the company designed a multi unit set for amateurs and these were available early in January 1921. "Radio News" in this month's issue advertised the sets. The sets failed to impress the radio public who did not want to be bothered wiring up six or so component units  when a complete set could be obtained cheaper from other sources. A tuner and three stage amplifier was then designed by Harold Tyzzer, one of the Amrad engineers, and this was put on the market. This set was found to contravene the Armstrong regenerative circuit patent and in October it was renamed as a short wave receiver. Orders for the new set could not keep up with the demand but by May 1922 it was obsolete. In January 1923 the set was modified. By Christmas demand for these sets outstripped supply.   


The Amrad crystal set was a very good seller and this tided the company over in troubled times. In March 1923 Amrad joined the Independant Radio Manufacturers Inc and this move enabled the company to acquire rights to the Hazeltine neutrodyne invention. It was not until December 1924 that the first neutrodynes were made and this was too late. Five months later, in April 1925 Amrad went into receivership. Powell Crosley of the Crosley radio Corp had made a successful regenerative radio circuit but as these were losing way to the newer neutrodyne receivers, he needed a lincense to make these. In December 1925 he purchased the Amrad factory, neutrodyne license and the Mershon condenses license. This was all for an outlay of US$39000. According to pages 25 and 26 of Morgan McMahons book "1922-1932 Radio Collectors Guide", there were 15 radios made by Amrad from 1921 to 1924 and 29 made from 1925 to 1929. From this, it is assumed that Crosley used the Amrad name on some raduios made by the company. The Great Depression saw the end of Crosley with it being sold to Magnavox.

As referred to above, Amrad also made gaseous rectifier tubes. They branched out with positive results for a gaseous rectifier developed by their engineer Charles Grover Smith. Smith waws hired in 1919 and did reserach into rare gas mixtures and spectroscopics. He made many notes of his investigations and his notes were referred to as the "S" papers. In February 1922 he presented a paper to the Institute of Radio Engineers on a rectifier device which required an external magnetic field. Within weeks he amended this device to a point where it could be enclosed in a glass bulb. This "tube" became the S tube (S apparently standing for Smith). QST magazine for June 1922, pages 11-13 has details of the new tube and its applications. It went into production in June 1922 and was given the type number S3000. It was not suitable for receiving sets an was sold for transmitter use. Its main function was to supply DC anode voltage to 5 watt transmitting tubes. Two S tubes (one each side of the line) could supply sufficient current for one 50 watt transmitting tube.      

Over the next two years more tubes were designed with different bulb shapes. One S4000 tube has been seen with a completely outside frosted glass bulb. The tubes were made in three shapes - pear shape, tubular and "Cone" (or Straight sided) and were only fitted with Edison Screw E27, or later, mainly E40 bases. The S5000, the last to be made was on the market in 1924. Smith's patents were sold to the American Appliance Company (later to become Raytheon) and Smith was hired by them to to be able to help Raytheon develop their own series of gas rectifier tubes.

Ref: Radio Manufacturers of the 1920's by Alan Douglas, pages 39-53 & 112

Some models:
Country Year Name 1st Tube Notes
USA  20 2331 Type E Crystal Receiver    
USA  23 107$    
USA  22 2575 Crystal Receiver    
USA  28 Power Pack (Power Unit) 171 ABC UX213  ABC power pack (power unit). The schematic diagram calls a 213. That is ambiguous. ... 
USA  23 2771 Vacuum Tube Detector UV200  The "Radio Collector's Guide 1921-1932" by Morgan E. McMahon lists this model on page 25 f... 
USA  23 3366    
USA  22 3380 3108 + 2634   Double-decker stacked set, including the 3108 & 2634 units. 
USA  23 Amrad 35 3500 3475 & 2634 UV201A  The AMRAD 3500 RF Receiver differed from the 3500-1 by the lack of a plug in RF transforme... 
USA  23 Amrad 35 3500-1 3475 & 2634   2 Box: 3475 & 2634.This model 3500-1 employs 2 selector switches (right and left of the lo... 
USA  23 Amrad 35 3500-2 3730 & 2634   2 Box: 3730 and 2634..THis model 3500-2 has only one (double arm) selector switch at the r... 
USA  25 Amrad 35 Inductrole 3500-3 UX201A  The Amrad 35 Inductrole model 3500-3 has two dials (primary tuning control knobs). 
USA  24/25 Cabinette 3500-4   Two dials (primary tuning control knobs) 


Further details for this manufacturer by the members (rmfiorg):

Scanned from the Amrad Radio Folder "Duet".tbn_amrad_folder_duet_p1~~1.jpg
Scanned from the Amrad Radio Folder for 1928.tbn_amrad_folder_1928_p1_part1.jpg
Scanned from the Amrad Radio Folder C.B.3 for 1929.tbn_amrad_folder_1929_part2.jpg
Scanned from the Amrad Radio Folder C.B.3 for 1929.tbn_amrad_folder_1929_p2.jpg
Advert 192xtbn_us_amrad_192x_plant.jpg
May 1921 AMRAD advertisement in Radio News magazine showing off the Amrad Selector set comprised of 6 AMRAD box sets. This is a short-wave loop receiver covering 175-350 meters.tbn_usa_amrad_ad_may1921radionews.jpg
May 1920 Radio News advertisement for AMRAD showing various early wireless productstbn_usa_amrad_may1920_radionews.jpg
December 1920 AMRAD rear cover advertisement from QST magazine.tbn_usa_amrad_ad_dec210qst.jpg
Advert 192xtbn_us_amrad_192x_address.jpg
Amrad made the first Mershon electrolytic condensers for radios. Picture from "The Crosley Broadcaster", Vol. VIII, No. 3., February 1, 1929, page 11 was sent by a guest.tbn_mershon_condenser.jpg
September 1922 Radio News advertisement. page 523tbn_usa_amrad_ad_sep22radnews180k.jpg
June 1921 Radio News magazine page 895tbn_usa_amrad_ad_june21radnews180k.jpg
February 1921 Radio News magazine page 508tbn_usa_amrad_nov21radionews.jpg
Original factory advertisement brochuretbn_usa_amrad_bel-cantoseries-1.jpg
Scanned from the Radio Retailing June 1927 page 187.tbn_rr_june27_p187_ad_amrad.jpg
December 1920, Electrical Merchandising magazine advertisement page 39tbn_usa_amrad_dec._1920_electrical_merchandising_page_39.jpg
December 1922, Commercial America magazine advertisement page 36tbn_usa_amrad_ad_dec._1922_commercial_america_page_36.jpg
QST magazine October 1924tbn_amrad_s_qst_1024.jpg

Forum contributions about this manufacturer/brand
Amrad Corporation; Medford Hillside (MA)
Threads: 1 | Posts: 1
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Konrad Birkner † 12.08.2014

Amrad baute bereits 1916 Funkgeräte (acht Feldstationen aus Sender, Empfänger, Stromaggregat mit Benzinmotor,auf je zwei Munitionswagen montiert), und auch weiter hin für die Regierung. Als dies mit Kriegsende abrupt ausfiel, bemühte man sich um den Amateurmarkt. Nach einem Konkurs 1925 Wiederaufnahme der Neutrodyne-Produktion unter Crosley. 1930 wurde die Firme geschlossen.

Quelle: (287)Erb

Amrad Corporation; Medford Hillside (MA)
End of forum contributions about this manufacturer/brand