Sensibly equivalent¶ to:
The 1L4 is a miniature voltage amplifier pentode with low filament current consumption. The Mullard equivalent from its 1950s range is DF92. It would be used for portable domestic radio equipment. The CV1758 is a direct equivalent.
The RCA datasheet shows tentative data for the 1L4 in 1942 but B7G based valves were made in the UK from the late 1940's onwards.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 44 mm tall.
References: Datasheet & 1040. Type 1L4 was first introduced in 1941.
Absolute Maximum Operating Conditions¶
Updated January 08, 2013. shape:thin.glass.tube construction:all.glass type:pentode age:1940.1950 base:b7g heater:1.4v pins:7 pin:1.f- pin:2.a pin:3.g2 pin:4.- pin:5.f- pin:6.g1 pin:7.f+