The CV1853 is an output valve, for frame timebase or audio and is equivalent to the commercial 6P25. The electrodes are obscured by the coating on the glass. It is pin compatible with the KT61 et al.
The reverse is plain.
The dome reveals that the valve is identical to the Mazda 6P25.
The classic envelope is 44 mm in diameter and, excluding the IO base pins, is 106 mm tall.
