The 6AR8 is a gated beam device. The similar 7360 was optimised for balanced modulator use. The 6AR8 is designed for synchronous TV detection, another balanced mixer application or for colour TV burst gating.
This exhibit has been over-printed with the Pinnacle name and Type designation, but under the print is the etched identification of the maker - General Electric.
Typical operating conditions are as a low power device. The deflector electrodes guide the electron sheet to one anode or the other.
The etched lettering is quite clear to the side of the Pinnacle name. Compare with 6AR8 and the origin is obvious.
The plain grey anode hides all the inner structure.
The thin glass tube envelope is 21 mm in diameter, and excluding the B9A base pins is 59 mm tall.
Reference: Datasheet. Type 6AR8 was first introduced in 1955.