DeWitt-LaFrance Co. Inc
54 Washburn Avenue in Cambridge, Massachusetts (1921)

This company originally made fountain pens and propelling pencils and branched out into radio manufacture in1922.
In August 1922 it applied to register the trade name Superadio. 

A patent was applied for in June 1924 for vernier dial for radios. The company was listed in the November 1924 Radio Trade Directory, under the heading of Vacuum Tube Sets, page 80, still at the Washburn Avenue address.

Late in 1925 the company branched out into radio tube manufacture, with the trade name EDLO. A rectifier (type GB) and a UX201A were two of the tubes known to have been made. No information has been found after the end of 1927.

Tube trade name EDLO

The De Witt La France Company, Inc. was formed by William P. De Witt and David J. La France some time between 1916 and 1918. De Witt was a well known Dentist and La France had been employed by Waterman and Moore in the manufacture of fountain pens. In the years from 1918 to 1921, the company made a wide range of fountain pens and propelling pencils with the trade name Superite. Several patents were applied for and granted on these. The factory was located at 23 Church Street, Cambridge, Massachusetts. Operations in pen and pencil making outgrew the premises and by late 1920, new premises were being sought.

The Cambridge Chronicle issue of January 1^st, 1921 announced that the company was settled in the new premises at 54 Washburn Avenue, Cambridge. The new factory was five times larger than at Church Street. The Cambridge Tribune of March 31, 1923 announced that the company was opening a branch in Illinois and this was registered at the Government offices in Springfield. The office was at 36 South State Street, Chicago, with D.L.Sterling as manager.

The company became interested in radio manufacturing in August 1922 and applied to register the trade name Superadio. On June 26^th, 1924 De Witt applied for a patent on a vernier dial and patent no 1537227A was issued for this on May 12^th, 1925. Radio News magazine for February 1926 shows an advertisement for the Superadio receiver and shows the Chicago representatives as being William A Welty and Co. There was also a Boston branch - Martin, Hartley and De Witt Sales Co., 99 Bedford Street. An advertisement for the Superadio was in "The Boston Globe", February 13^th, 1927.  

In addition to radio receivers, the company also made the "Superadio B and C" combination battery eliminator. This was advertised in "The Boston Globe" on September 26^th, 1926. The company entered the tube manufacturing business during late 1925 - early 1926 with at least two tubes branded EDLO. One was a rectifier to go with the battery eliminator and was a gaseous tube, type GB. One other EDLO tube that has been located is a UX201A. The company also made the"Dynometer" tube tester.

There is no listing for the company in the 1928 Cambridge (Business) Directory, so it woud seem that the company was no longer operating.