Western Electric Co. Ltd., Connaught House, 63 Aldwych, London WC 2.

In May 1883, Western Electric (USA) opened a small office and store in London. The business continued to grow and in 1910 they formed the private company Western Electric Co. When the International Telephone and Telegraph Company (ITT) acquired the international operations of Western Electric in September 1925, the company was renamed to Standard Telephones and Cables Ltd. (STC).

The Western Electric Co, Inc of Chicago and New York opened a small office and store in London in May 1883. The location of the office and store are not recorded in consulted reference material. In 1898 the company purchased a failing cable company at North Woolwich and made lead sheathed cables, vulcanised cables and assembled equipment imported from Belgium and the US. Shortly after this, complete manufacturing processes were achieved. In 1910 the Western Electric Co Ltd was incorporatedand became a wholly owned subsidiary of the International Western Electric Company of the USA.  

In 1914 the company installed a sophisticated telephone exchange at Darlington and was also making telephones and associated apparatus. Other exchanges were installed at Dudley and in 1922 the British Post Office adopted the "Strowger" system as its standard exchange. 

During World War One the company was involved in the War Effort and this gave them a post war advantage as wireless broadcasting was introduced in the United Kingdom.

The company had outgrown the North Woolwich factory and a large factory site with its own railway siding was purchased a Oakleigh Road, New Southgate in 1922. This site was several acres in size and this allowed for great expansion in the next few years and beyond. Here in the following year, radio sets were manufactured as well as horn speakers and other radio equipment. There was also a tube making department. In 1922 the company was one of the six British companies that set up the British Broadcasting Company (later Corporation) (BBC)

The first tubes made were of the American WE design, such as 101D and 215A "Peanut" tube. To distinguish these from the US made tubes, each type number was preceded by a 4; thus the 101D became the 4101D and the 215A became the 4215A etc. Other tubes were made with the company name until 1925 but little is known about specific tube types. The name "Wecovalve" was adopted for at least the "Peanut" series.

In May 1925 the International Western Electric Co was acquired by ITT (International Telephone and Telegraph Company). These interests were transferred to the International Standard Electric Corporation of New York. Its British subsidiary's name was changed to Standard Telephones and Cables Ltd   

References:

Grace's Guide to British Industry

British Radio Valve The Vintage Years, Keith Thrower, 199, page3

Various Wecovalve advertisements