The three companies covered here were all creations of a prolific engineer and entrepreneur, Harold W. Ulmer. His life is summarized in the biography link to the left. All his companies were located in Oceanside, California, a sleepy coastal town at the north end of San Diego county, just south of the Camp Pendelton marine base.
Vacuum Tube Products was run out of Ulmer's parents garage and basement, starting in 1936. Ulmer went back east during World War II, working at Federal Telegraph Co. and then Raytheon, but upon returning in 1946, restarted Vacuum Tube Products. He started making picture tubes in 1948, and in 1949 made the first rectangular CRT west of the Mississippi. He went on to make many special tubes, vacuum equipment, welding machines, and CRTs, including the first storage tubes for Hughes Aircraft. Hughes was so impressed that they bought Vacuum Tube Products in 1959.
Harold Ulmer wasn't a big company guy, and left Hughes in less than a year. He then started H.W. Ulmer Co. in 1959, concentrating on welding and high-vacuum equipment and tubes. Several employees from Vacuum Tube Products rejoined him at H.W Ulmer Co. H.W. Ulmer Co. merged with Denver-based Microtron and concentrated on making welding equipment. Due to back problems, Harold left Microtron in 1963.
In 1965, Harold Ulmer combined his old H.W. Ulmer Co. with McEwen Enterprises to form M U Inc. (McKewen-Ulmer). Lillian McEwen was a production supervisor at Vacuum Tube Products. M U (which is pronounced "Em You", not mu, the Greek letter) specialized in making small production runs of tubes for the military and avionics companies, typically tubes no longer manufactured by other tube companies. Ulmer's past background in making many types of tubes allowed him to tool-up and make pretty much any tube needed. His youngest daughter, Ronalee Elsberry (known as Roni), worked at M U starting in the 1970s. When Harold Ulmer died in 1997, Roni took over the company and continued serving the military tube market. In 2018, Roni decided to retire, and M U was shut down.
Various documents from Harold Ulmer's three companies are provided here, separated by company and listed chronologically.
Vacuum Tube Products 1952 Brochure - A 16-page brochure intended for prospective customers. Contains: a list of production equipment, customers, biographies of key employees, and photographs of different aspects of tube production. Quite a detailed snapshot of VTP in 1952.
H W Ulmer Co 1961 Company Resume - A brochure for intended customers of the H.W. Ulmer Co. part of Microtron. This is before they got into making the large welding machines. Has photos of the 2941 and 3018 San Luis Rey Road buildings.
Microtron 1962 Summary of Annual Meeting - As the title says - a fairly light-weight summary of the company. By the way, Ed Gaylord, one of the board members, was a billionaire and the richest man in Oklahoma.