The TY7-6000A is a RF power output valve with a maximum rating at up to 30 MHz. The maximum quoted operating frequency is 50 MHz, but the similar TY6-5000A was rated at both 48-75 MHz and 170-220 MHz.
The output power is rated as 6 kW and the grid current has to be limited to 500 mA. The press release indicates that the TY7-6000 Type is designed for industrial RF heating applications where voltages and load can vary widely. Mullard also advertise this valve for high power audio applications.
As well as having a glass to metal anode seal the base is of the all glass type without a pinch. The grid is connected to the ring that divides the main glass envelope and the bright metal cone connects the envelope ring to the grid proper.
From the side the grid support and the bright copper anode can be seen within the glass. Note the absence of gettering. This is normal in high voltage power valves. The grid ring is 65 mm in diameter.
The final picture shows the cooling fins for forced air cooling of the anode, they are 122 mm in diameter and 94 mm long.
The wide glass tube envelope is 53 mm in diameter, and excluding the base pins is 192 mm tall.
Reference: Datasheet. Type TY7-6000A was first introduced in 1956.