Type 8025 is a VHF/UHF transmitting triode and is electrically an 8012 on a UX4 base. The 8012 has a thoriated tungsten filament as did the earlier 1628. The filament is wound as a double helix and is centre tapped to minimise filament inductance effects.
The control grid can pass up to 14 mA grid current and dissipate 1.6 W. The maximum frequency of operation is in the region of 500 MHz.
The grid and anode connections are brought out to top caps rather than the stiff wires of the 8012. The base has the RCA logo as well as the Type designation.
The anode and grid both have a pair of connectors.
The thin glass tube envelope is 25 mm in diameter and, excluding the UX4 base, is 105 mm tall.
References: Datasheet & 3002. Type 8025 was first introduced in 1943.