Siemens Super 521 W – Austrian Tube Radio from 1951/1952

The Siemens Super 521 W, also listed as Siemens-Austria WSW Mittelsuper 521W, is an Austrian table radio from the early 1950s. It was produced by Siemens-Austria / Wiener Schwachstrom Werke (WSW) in Vienna around 1951/1952.

This set belongs to the generation of post-war European domestic receivers that still relied entirely on the classic AM broadcast bands. It covers long wave, medium wave and short wave, but does not yet include FM. In this respect, the 521 W represents the last strong phase of traditional AM radio design before FM receivers became increasingly common in Austrian and German households during the 1950s.

Technically, the radio is a six-circuit AM superheterodyne receiver with an intermediate frequency of 452 kHz. The valve line-up is typical for a well-equipped early-1950s AC mains set: ECH21, ECH21, EBL21, AZ21 and EM34. The EM34 magic eye gives the radio the characteristic visual tuning indication of better post-war receivers.

The “W” version is an AC mains receiver, specified for 110, 125, 150 and 220 V operation. This distinguishes it from all-current “U” sets, which used a different valve series and did not rely on a conventional mains transformer. The set is housed in a wooden tabletop cabinet and uses a 17 cm dynamic loudspeaker. With its relatively modest size, simple front layout and short-wave band spread, it is a good example of a practical Austrian middle-class receiver of its period.

Technical Data

Restoration Notes

This Siemens Super 521 W is currently documented in its as acquired condition. No restoration work has been carried out yet.

Circuit Diagram

References

• Radiomuseum.org — Siemens-Austria WSW Mittelsuper 521W.
• Radiomuseum Croatia — Siemens MITTELsuper 521W.

Pictures