The UF89 is an internally screened variable μ pentode designed for VHF applications in Band I and Band III televisions. It is a low impedance device and may have found application in receiver front ends.
Looking through the mesh of the outer screen the three grids can be seen. The anode is formed from two small plates strapped together top and bottom.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A pins is 53 mm tall.
References: Datasheet & 1040. Type UF89 was first introduced in 1955.
Absolute Maximum Operating Conditions¶
Updated January 04, 2016. shape:thin.glass.tube construction:all.glass type:pentode age:1950.1960 base:b9a heater:100ma pins:9 pin:1.s pin:2.g1 pin:3.k pin:4.h pin:5.h pin:6.s pin:7.a pin:8.g2 pin:9.g3