Radio ontvanger Model 438 (Beacon Receiver Model 438 - Detrola; Detroit MI)

The Beacon Receiver Model 438 is the version produced by Detrola of the Beacon Range Receiver identifed as BC-1206. Another version is the Model 524 Beacon Receiver produced by Setchell Carlson. The 524 and 438 are physically interchangeable and have almost identical performances (200-400 KHz coverage, 3-5 uV sensitivity for 10 mW output, current drain of 0.75 A at 24 V, power output of 300 mW and provision for 300 ohm or 4000 ohm headsets) but, despite the common architecture, rely on remarkably different realizations and tubes (14A7,14A7,14J7,14R7,28D7 for the 524 and 6K7,6SA7,6SK7,6SQ7, 28D7 for the 438; moreover Detrola has realized also a second version of the 438 with 6 tubes where the 28D7 has been substituted with a pair of 25L6). The 524 and the 438 have also different IF frequencies (135 KHz the first, 142.5 KHz the second). The receiver was not intended for direction finding but only for establishing whether a specific beacon station could be received and was endowed with a short antenna.