The 20L1 from Mazda is from the early days of all glass construction in the UK i.e. 1947-49. This is a low impedance amplifier double triode and could have found uses in a wide variety of equipment. The 12.6 Volt heater requirement makes this particularly suitable for vehicle use, likewise the 200 mA current rating makes it suitable for television use. The 6L1 is identical except for a 6.3 Volt heater.
The twin triodes without a central screen.
Made in England and a face view of one triode.
The thin glass tube envelope is 20 mm in diameter and, excluding the B8A base pins, is 53 mm tall.
