Type 6AN8A is a triode pentode (but here built as a triode beam tetrode) with a defined warm-up time for use on series heater chains. The pentode section is used as a video amplifier or reactance valve while the triode performs variously as a phase detector, gating valve, oscillator or phase splitter.
The triode is on the right separated from the pentode by an electrostatic screen. The pentode anode has two plates with a strap joining them.
The two inner grids and the beam plates within the anode.
Looking straight into the pentode. The bright plate at the back is the screen. The inner wire grids are formed to pass flat across the cathode. The double micas suggest a vibration resistant design.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 47 mm tall.
References: Data-sheet. Type 6AN8A was first introduced in 1954. See also1954 adverts.
