The 7077 is a sub miniature UHF amplifier triode. It is resistant to shock, vibration and nuclear radiation. Operation in grounded grid mode is shown in the data-sheet.
Probably not designed for domestic TV sets!
Top to bottom: anode, control grid, cathode ring and heater pins. The date looks like April 1968.
The flat top to the gold plated anode.
The thin ceramic tube envelope is 8 mm in diameter and, excluding the base pins, is 10 mm tall.
Reference: Data-sheet. Type 7077 was first introduced in 1962. See also1962 adverts.
