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History of the manufacturer  

Moorhead Laboratories (Pacific); San Francisco

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Name: Moorhead Laboratories (Pacific); San Francisco    (USA)  
Abbreviation: moorhead
Products: Tube manufacturer

Moorhead Laboratories; San Francisco

Founded: 1915
Closed: 1924
Production: 1915 - 1922

Otis B. Moorhead was born January 9, 1893 in San Franciscoadd, dying from injuries, the result of an accident, on January 31st, 1923. His death was carried in the San Francisco Examiner the following day. He was interested in wireless from the early age of eight and was inspector for Marconi Wireless in 1914, working also with Major Allen Forbes. In 1915 Moorhead worked evenings in the DeForest booth at the Panama-Pacific Exposition, selling audions. He decided to manufacture tubes and got some money from Forbes and Kendrick. An office was set up on the 4th floor on 650 Mission Street in San Francisco with a P.O. Box for an address. In early 1915 Moorhead and E.T. Cunningham collabortated on the first desgn of a gas detector tube, but then went separate ways. Cunningham advertised his Audiotron October 1915 and Moorhead had his first ad in July 1916 with the words "The former manufacturers of the Audiotron are now manufacturing a new and better Tube.".

The tubular Electron Relay (ER) was produced in 1915 by the help of Ralph Hyde, a former G.E. lamp factory superintendent and before expert glass blower at Oakland Mazda Lamp works. There were only a few tubes made of this type and the details of construction are not known. Early 1916 DeForest brought suit, but since the validity of the DeForst Audion patent was being challenged in the courts by Marconi, an injunction was not granted but a bond was required as a condition of continued production until such time as the Audion patent dispute was settled. After posting the required indemnity bond, Moorhead did publish ads for the second Electron Relay - with the first picture in "The Electrical Experimenter" of August 1916 (Tyne names July for a first ad). Moorhead used as name "Pacific Laboratories Sales Department, 534 Pacific Building, San Francisco.

Tyne page 170: "In February 1917 the Pacific Research Laboratories were taken over by the Moorhead Laboratiories, Inc., although advertisements for the Moorhead tubes continued to be signed by the Pacific Laboratories Sales Dept."

Following the formation of RCA in 1919, The Marconi Wireless Telegraph Company of America informed Moorhead in January30th, 1920 that Moorhead must cease operations by June 30th the same year. Moorhead ran out of capital in March 1920 and considered bankruptcy. Henry Shaw came from New York to San Francisco and in return for a 75% share in the company, reorganized it and became sales manager. He was elected president on May 30th. He also opened a new tube base factory. At this time, all old inventory had been sold to the Westinghoouse Electric and Manufacturing Company qand early Westinghouse tubes used the old Shaw bases from this purchase and possibly some element assemblies. Moorhead and de Forest then formed a partnership and began making tubes tubes again under the names Atlantic Radio Supplies and Pacific Radio Supplies. de Forest was appointed to the board and was influential  in having some of his tubes, such as the "Singer" Oscillion made at the factory. Some tubes had steel stamped bases with the name de Forest and the Marconi logo on the bases, following an agreement with Marconi. This license expired in July 1920, thus meaning that Moorhead tubes now infringed the Fleming patent, with his A-P tubes. An agreement was entered into with with RCA so that Moorhead could continue making a specific number of tubes under a temporary license. The company ceased operations in mid 1922.

The first ER tube was made in April 1915 and Moorhead registered two companies in the same year to make and sell his tubes. The manufacturing company was the Pacific Research Laboratories and the sales company was the Pacific Laboratories Sales Department. QST magazine of September 1916 shows an advertisement for the external grid tube.

In the meantime, the Atlantic-Pacific Radio Supplies Co was formed in August 1921 with Henry M Shaw as president. Willis M Deming was president in May 1922 and also president of the Atlantic-Pacific Sales Co a year later.

The "A-P One" radio was advertised by the A-P Radio Supplies Co in May 1922. It was made for them by the Radio Shop of an Jose, California. The front cover of "Radio" Magazine for October 1922 shows an advertisement in which Atlantic-Pacific Radio Supplies Co was involved with the Oard Radio Laboratories as a supplier of tubes as used in such sets as the "Oard Phantom Receptor". The Portable Radio Company was the chief distributor of the Oard line of radios. Oar wasone of the companies licensed to use the Armstrong Regenerative circuit, which was patented. Due to legal problems, sales of tubes dwindled to a point that after May 1923, no advertisements showed any involvement with Oard. At thistime, qan application was submitted to change the name of the company to the Atlantic-Pacific Sales Company. This was on May 9th.     

On November 11th, 1922, Moorhead announced plans for a totally new company "Universal Radio Improvement Company", with a large pant to be built in Alameda, California. The facilities were to enable the factory to make one thousand tubes a day (which was an overstatement). A former X-ray technician, Henry K Huppert, was engaged to work on tube design of one of these was the A-P Solenoid tube, a non infringing type. No records of the Company's incorporation have been found, leading to the assumption that Moorheads death two months later lead to the new ventures demise. The Charter for Moorhead Laboratoriews Inc was allowed to lapse in January 1924.

The A-P Sales Company officially ceased operations on January 1st and the A-P Laboraories ceased in May 1925. From 1915 to 1925, Moorhead had four tube concerns and five sales concerns

The offices of Moorhead Laboratories were located in the Call Building, 703 Market Street (corner of 3rd Street), San Francisco. The factory was at 63 to 640 Misson Street from World ar One until August 1922, when they moved to smaller premises at 648 Mission St.        

NB Please also see:

Atlantic-Pacific Radio Supplies Co.



1) Saga of the Vacuum Tube, G F J Tyne, pages 146, 170-175, 178, 300 and 331

2) Moorhead Article www.bill01A

3) Otis B Moorhead and the Vacuum Tube Tangle, Eric Wenaas, AWA Review No 

    2, pages 51-128 

Some models:
Country Year Name 1st Tube Notes
USA  17 Panel Set No. A1 ER_Moorhead-1917  In 1917 the Moorhead Laboratories advertised the Type A2 Panel Set for use with their l... 
USA  17 Panel Set No. A2 ER_Moorhead-1917  In 1917 the Moorhead Laboratories advertised the Type A2 Panel Set for use with their l... 


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

August 1916, The Electrical Experimenter magazine advertisement on page 273 showing the first Moorhead Electron Relay tube.tbn_usas_pacific_laboratories_moorehead_er_relay_august_1916_elex_page_273.jpg
May 1920, The Electrical Experimenter magazine advertisement on page 8tbn_usa_pacific_radio_lab_ad_may_1920_elec_exper_page_8_rm.jpg
July 1920, The Electrical Experimenter magazine advertisement on page 336tbn_usa_pacific_radio_lab_ad_july_1920_elec_exper_page_336.jpg
January 14th 1920 San Francisco Chronicle newspaper Article showing the evacuation process in the Moorhead laboratories.tbn_usa_moorhead_jan_15_1920_san_fran_chronicle.jpg
June 1920 Pacific Radio News magazine advertisement on page 417 (inside rear cover)tbn_usa_moorhead_june_1920_pacific_radio_news_page_417.jpg
March 1917, Pacific Radio News magazine advertisement on rear covertbn_usa_moorhead_mar_1917_pacific_radio_news_inside_rear_cover.jpg

Forum contributions about this manufacturer/brand
Moorhead Laboratories (Pacific); San Francisco
Threads: 1 | Posts: 1
Hits: 1982     Replies: 0
Pacific Laboratories Sales models
Alan Larsen

Apparently The Pacific Laboratories was involved in much more than just the manufacture and sales of Moorhead tubes after the takeover by Moorhead Laboratories in February of 1917. Here is an advertisement offering a whole range of sets and parts in a June 1917 Electrical Experimenter magazine. 


Moorhead Laboratories (Pacific); San Francisco
End of forum contributions about this manufacturer/brand


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