The 76 is general purpose amplifier triode, designed for use as oscillator, detector or amplifier. The characteristics are identical to Type 56 except that the 56 has a 2.5 Volt heater - the original USA standard for mains valve heaters.
The Triotron identification and the word Foreign to denote an import.
The triode mounted high in the envelope and held in place by the mica tightly fitting the shoulder of the glass.
Side view also showing the rectangular mica sheets holding the top mica flat.
The classic envelope is 38 mm in diameter and, excluding the UX5 base pins, is 87 mm tall.
References: Data-sheet, 1040 & 3002. Type 76 was first introduced in 1940. See also1940 adverts.
