PC88 Haltron SQ
The PC88 is a UHF triode designed for grounded grid operation in the front-end RF amplifier in Band IV and Band V television tuners. Mullard describes the PC88 as a UHF frame-grid grounded grid amplifier triode. The construction is planar. The flattened cathode has a frame grid to one side only, beyond the grid is a square U channel anode with its flat end to the grid. The approach to minimize the lead inductance is to use multiple pins for the grid connection. The relatively high anode current was employed to reduce noise.
Mullard designed a UHF TV tuner around the PC88 operated as a grounded grid amplifier and a PC86 self-oscillating mixer. These designs date from 1961.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 47 mm tall.