The RCA 5734 is described as a mechano-electronic transducer. The top of the body can rotate about the rest by ±0.5 degrees and this rotation alters the anode to grid spacing and this the anode current. Thus the design is a transducer that responds to vibration. The 5734 can work up to 12,000 cycles a second.
The valve was measured with the protective sleeve in place.
The general form of the 7534. The copper sleeve is present to protect the top pin.
The top pin and flexible diaphragm.
The evacuation tube and printed lettering. The name RCA is present around the circumference before USA.
The glass base showing some wires that are anchor points in the glass and do not get connected to the flying leads.
Another view of this unusual valve.
The thin metal tube envelope is 8 mm in diameter, and excluding the base wires is 24 mm tall.
Reference: Datasheet. Type 5734 was first introduced in 1948.