The STV 100/60Z is a precision cold cathode voltage stabiliser. It was used in Sightgerat oscilloscope and STV is a brand of the German Telefunken company, and this exhibit carries the Telefunken logo. STV was taken over by Telefunken.
This stabilises to 100 Volts and has a maximum current of 60 mA. Our exhibit is on a B4 base but it was also produced with a B9D Magnoval base.
The electrodes are three concentric cylinders. The small height cylinder is positioned very close to the inner cylinder. The outer ring is the anode.
The Telefunken Logo. The other side carries the STV logo but that is concealed beneath BWB952.
The wide glass tube envelope is 28 mm in diameter, and excluding the B4 base pins is 68 mm tall.
References: Datasheet & 3002. Type STV100/60Z was first introduced in 1957.