The Fenomen Mz 744 is a tabletop vacuum-tube radio, with a mains AC power supply. It was launched on the market in the 1937/1938 season by Krajowe Towarzystwo Telefunken sp. z o.o. – the Polish branch of the German radio technology corporation. The Warsaw branch of Telefunken manufactured radios under a foreign licence, but they were designed in Poland and adapted to local technical conditions. The Fenomen is a four-circuit superheterodyne receiver built on iron cores, equipped with four vacuum tubes and a reaction detector. Such a configuration was not widely used, and it is a trademark of Telefunken’s models. The manufacturer used a range of interchangeable lamps of its own manufacture. In order to limit the use of vacuum tubes made by competitors, a warning is placed on the back of the receiver that reads: “Caution! The TELEFUNKEN vacuum tube types used in the receiver must not be replaced with others; even if other tubes work well initially, the performance of the radio will decrease over time”. The receiver allows the reception of radio stations in short, medium, and long wave bands. The electrical system and design solutions of the Fenomen receiver were based on the Lord model. The Fenomen was marketed in three versions; apart from the Mz 744, they were the Mu 744 with DC power supply and the battery-powered Mb 713. After 1935, a horizontal layout of radio receivers became popular and the Fenomen was designed in accordance with that trend. The chassis was enclosed in a wooden cuboid box covered with a walnut veneer, and its two front side edges were rounded. At the base of the front wall there is a flat, elongated trapezium cut-out, giving the shape of the radio an impression of lightness. In the front wall there is a rectangular cut-out finished with a glossy aluminium bezel. Inside it is a dark walnut panel, symmetrically divided into two narrower rectangular fields of identical sizes, with rounded corners. On the left, behind a glass pane, there is a flat tuning scale with a sliding arrow, while on the right, behind a fabric cover, a Telefunken Navi dynamic speaker is placed, with – as the promotional materials claim – “a broad-ribbon membrane with a melodious and strong tone”. Below the scale there are three Bakelite rotary switches with metal caps. The knob on the left, which is decorated with three linear symbols, is responsible for changing the band, the middle one is for tuning, and the one on the right – controls volume.

Author: Filip Wróblewski