EL33, MULLARD, OLD SHIELD, WHITE PRINT, PENTODE, 6AG6G, 6M6G, BVA266, CV2938, KT61, N147, PP6BG (Copy)

EL33,  MULLARD, OLD SHIELD, WHITE PRINT, PENTODE, 6AG6G, 6M6G, BVA266, CV2938, KT61, N147, PP6BG

The EL33, introduced in 1939 is considered the EL37's smaller less powerful brother.  It is actually a pentode but it’s both pin and electrically equivalent as well as being easier to drive whilst showing lower intermodulation distortion and was introduced at the same time as the KT61 in 1939.

This example is a nice device showing superb emission and nice Mullard Old Shield printing,