Burndept: the well established Burnham & Co had a wireless department, which became a separate entity when Witt Burnham established Burndept Ltd. as a private company.

Ethophone was the popular name for a number of models.

1925 they became a public company: Burndept Wireless Ltd. which later ran into financial problems: in June 1927 it was forced into receivership (Konkursverwaltung). But the company was not liquidated. The receiver (Konkursverwalter) took control and managed to recover to profitable working.


Ref.: Geddes/Bussey: The Setmakers

In 1925 Burndept introduced a series of valves: one bright emitter valve H.L.565, and eight dull emitter types.
After Burndepts bankruptcy in 1927 they ceased manufacture of valves and concentrated solely on radio equipment.
Ref.: Keith R. Thrower, British Radio Valves, The Vintage Years: 1904-1925.