The 150/40Z from STV is a commercial voltage stabiliser that also carries the designation LK199. This exhibit was made for the Wehrmacht during the period 1936 - 1945 in Germany.
The base is a three pin S3B type. STV name their stabilisers by their rating and thus we have some operating details. The stabilised voltage is 150 Volts for currents around 40 mA.
The Testing station BAL716 and the fact that it is government property.
The base pins.
The alternate designations of LK199 and Ln28729.
The main cylinder is closed at the top and sealed below with a ceramic disc. The second electrode is a central wire. Note the locating key on the plastic base cap.
The wide glass tube envelope is 35 mm in diameter and, excluding the S3B base pins, is 59 mm tall.
Reference: Observation. Type 150/40Z was first introduced in 1941. See also1941 adverts.
