1L6

The 1L6 is a 7 pin miniature vacuum tube of the pentagrid converter type. It was developed in the USA by Sylvania. It is very similar electrically to its predecessors, the Loktal based 1LA6 and 1LC6. Released in 1949 for the Zenith Trans-Oceanic shortwave portable radio, this tube was in commercial production until the early 1960s .
The 1L6 was to be a specialty tube, produced in small quantities by very few manufacturers, mostly Sylvania for use by just a few manufacturers of shortwave portables, such as Zenith - in their Trans-Oceanics - and its short-lived rivals, such as the Hallicrafters TW-1000 and the RCA Strat-O-World and very few others.
Despite the limited application for 1L6, today NOS examples bring relatively high prices. Many radio collectors overcome this expense by using the more commonly available 1R5 with pin 5 cut off.

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