The E1733 is a full wave indirectly heated rectifier. The 6.3 Volt heater runs at 1.6 Amps and that is a considerable heating power and that suggests a significant current rating. It also runs the heaters very bright orange. At 5.0 Volts the consumption is 1.42 Amp and the colour appears correct. It is possible that the 6.3 Volt annotation is wrong. The design is similar to the 7Z4. A guess is a rating of 450 Volts at 120-150 mA. The GZ34 has heater power of nine watts and a rating of 550 Volts at 160 mA.
The serial number and the carbonised stitched anodes. The heater and cathode connections are made at the top.
One section showing heater and cathode connections. The single hairpin insulated heater can be seen emerging from the base of the cathode tube.
A close-up of the top mica and connections.
The wide glass tube envelope is 32 mm in diameter, and excluding the B8B base pins is 70 mm tall.