The PCF86 is a VHF TV frequency changer. It has been designed for the triode oscillator to supply 3.2 Volts peak to peak to the pentode mixer section. The PCF806 is an improved form of the PCF86.
The triode section - copper supports for the control grid.
The screen plate below the lower mica shields the anode and screen grid.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 48 mm tall.
References: Data-sheet, 3002 & 1040. Type PCF86 was first introduced in 1960. See also1960 adverts.