The radio equipment made by the Marconi Wireless Telegraph Company of America listed below, has been catalogued from two main sources. The first primary source are the engineering drawings "Finding Aid" prepared by Anastasia Day of the Hagley Museum and Library, Manuscripts and Archives Department. A copy of this PDF document can be found here. The drawings are organized by filing numbers from early RCA historian George H. Clark. Clark’s catalog numbering system was an extension/adaptation from a US Navy classification system. Equipment extracted from this document bears a specific date. It is presumed, that the drawing date and the in-service date for the equipment are relatively close to each other.The second primary source is a spreadsheet of equipment provided by the Infoage library web site . An Excel copy of the spreadsheet can be found here. A great deal of care was exercised when radio information was being extracted from the document. Many of the ubassemblies were identified with the same model number as a complete receiver or transmitter.
The equipment list is by no means complete. If you can help to enhance this listing, please contact: Jerry.proc@sympatico.ca
MODEL # FUNCTION POWER/NOTE WAVELENGTH CIRCA COMMENT 1000 watts 60 cps Transmitter 1 kw, 60 cps 300 or 600 meters No type number assigned by Marconi 2000 watts 240 cps Transmitter 2 kw 240 cps 300 or 600 meters No type number assigned by Marconi ? Transmitter 3 KW ? No type number assigned by Marconi ? Transmitter 10 kw, 500 cycle ? 1915 February 16. . US Signal Corps proposal ? Transmitter 20 kw ? 1918, Sept 26 . Used at Fort Sam Houston ? Transmitter 25 kw ? ? Disc discharger BC14A Receiver n/a ? ? Signal Corps. a.k.a. SCR-54A C296-B Transmitter 0.5 kw ? ? C3 Transmitter (?) ? ? ? Army Cart set Detector Types CM Switchboard ? Radio switchboard CM 98 (Note 1) ? ? Motor boat set CM 294 /B/C Receiver n/a 250 to 3100 m ? CM 296 Transmitter 0.5 KW 300 to 952 m ? Paired with type 106 receiver CM 297 Transmitter 5 KW ? 1918 March 28 CM298 Transmitter 5 KW ? Navy set. 120 and 230 VDC CM299 Transmitter 5 KW ? Navy set. 120 and 230 VDC CM 300 Transmitter 5 kw ? ? CM 301 Transmitter 5 KW ? 1918 March 12. CM 305 Transmitter 2 KW ? 1918 December 24 US Navy auxiliary transmitter. CM 306 Transmitter 2KW ? ? CM 307 Aux xmitter 2 KW ? 1918 October 24 CM 309 Transmitter 1 KW ? 1918 February 27. . For US Navy CM 314 Transmitter ? ? ? CM 416 Switchboard n/a ? ? CM 425-1 Key 1917 For US Navy CM 858 Transmitter 5 KW ? 1918 May 23 CM 1122 Transmitter 2 KW ? 1918 September 25 CM1123 Transmitter 5 KW ? ? CM 2946C Receiver n/a 250 to 3100 meters 1917 For US Navy Composite Transmitter 2 kw 60 cycle ? E2 Transmitter 1/2 kw 120 cycle 300 and 600 meters Fleming Valve Tuner Tuner/ Detector 300 to 1650 meters Converted to type 107A tuner Headphones n/a n/a ? For US Navy Key - 5 kw Key 5 kw Made for Signal Corps M1 ? ? ? ? Mule pack set P1 Transmitter 5 KW ? 1916 Dec 21. P3 Transmitter 2 KW, 500 cycle ? 1915 January 2 Supplied on US Navy contract no. 21,507. P4 Transmitter 2 KW, 500 cycle 300/450/600 meters
Sept 1915? Panel transmitter family. P4A Transmitter 2 KW, 500 cycle ? ? P4B Transmitter 1 KW 500 cycle ? ? Panel transmitter family. P5 Transmitter 0.5 KW, 500 cycle ? 1915 August 14. Panel transmitter family, P6 Transmitter 5 KW, 500 cycle ? 1916 February 25. P8 Transmitter 2 KW ? 1919 December 17 Mated with receiver type 106 B P9 Transmitter 1/4 kw 500 cycle 300/450/600 meters Cargo set P11 Transmitter 0.5 KW ? ? P13 Transmitter 0.5 KW, 500 cycle ? 1917 March 19. P18 Transmitter 1 KW, 500 cycle 1918 October 2 300, 600 and 952 meters
MODEL # FUNCTION POWER/NOTE WAVELENGTH CIRCA COMMENT SCR-54A Receiver n/a 200 to 600 m a.k.a. BC-14A SCR 105 Trench Rx and Tx ? ? 1918 September 20 Quenched gap transmitter SE 68 Key ? n/a ? Auxiliary key SE 80 Switchboard n/a ? ? Radio switchboard. SE 81A Switchboard n/a n/a ? Radio switchboard SE 81B Transmitter 2 KW ? 1918 June 12. . SE 84 Tone Tester n/a n/a 1918 SE 86 Key 1/2 kw n/a ? Flameproof key for submarine radio SE 87 Transmitter 5 KW ? ? SE 89 Transmitter 2 KW ? ? SE 90 Transmitter 2 KW ? ? SE 95 Receiver n/a Long wave ? SE 108 Transmitter ? ? 1918 January 25. SE 109 Transmitter ? ? 1918 January 25. Quenched gap transmitter SE 150 Leyden Jars n/a n/a SE 327 Transmitter 10 KW ? ? SE 328 Transmitter 10 KW ? ? SE 653 Transmitter 0.5 KW ? ? Flameproof key for use in submarines SE 970 Transmitter 2 KW ? ? SE 1000A Amplifier n/a n/a ? Two stage AF amplifier SE 1100 Transmitter ? ? 1918 May 2 Flying boat transmitter. SE 1205A Transmitter 2 KW 1918 September 8. SE1060 Transmitter ? ? 1917 SE 1405A Amplifier n/a n/a ? Six stage AF amplifier SE 1420-A and B Receiver n/a ? ? Medium wave receiver SE 1443-A Key ? n/a ? Flameproof key SE 3519 Test buzzer n/a n/a ? Standard 1 KW Transmitter 1 KW ? ? Standard 2 KW Transmitter 2 KW ? ? S1 Switchboard n/a -- -? Switchboard for P6 Station Wavemeter Wavemeter n/a ? ? Type A Xmitting key Up to 4 kw n/a ? Type D Tuner -- ? ? Type E Tuner -- ? ? Type ' I ' Antenna switch 10 inch Coil 21 Wavemeter n/a ? ? 22 Wavemeter n/a 200 to 750 m 1914 24 Decremeter n/a ? ? An instrument for measuring the logarithmic decrement of electromagnetic waves. 25 Wavemeter 2 KW ? " 26 Decremeter n/a ? ? 27 Wavemeter n/a ? ? 28 Wavemeter n/a ? ? 101 Receiver n/a ? ? 102 Tuner n/a ? ? 103 Tuner n/a 105 Receiver n/a ? ? 106 Series Receiver n/a 200-3500 m 1915 107A Receiver n/a 300 to 3000 meters 1917 110 Receiver n/a ? ? 111 Receiver n/a ? ? 112 Receiver n/a ? 1917 Cargo set 113 Receiver n/a ? 1917 April 11. 117 Receiver n/a ? ? 118 Receiver n/a ? ? 119 Receiver m/a ? ? 120 Receiver n/a ? ? Signal Corps receiver 121 Receiver n/a ? ? Signal Corps receiver 122 Receiver n/a ? 1918 Signal Corps receiver 294 (See CM294) Receiver -- 250 to 3100 m ? 380 Transmitter 2 KW ? 1919 October 11. 442 Transmitter 2 KW ? ? Belt driven transmitter 444 Transmitter 0.5 KW ? ? 463 Control box n/a n/a ? Audio control box 531 Transmitter 0.5 KW 500 cycle 300 to 1,000 m 1920 August 12. . Note 1: CM is the two digit manufacturing code for products produced by the Marconi Wireless Telegraph Compamy of America
This table lists typical aerial currents on some of the American Marconi transmitters.
| TYPE OF TRANSMITTER | 300 METERS | 450 METERS | 600 METERS |
| 2 kw 500 cycle | 3 to 5 amps | 9 to 13 amps | 12 to 17 amps |
| 1/2 kw 500 cycle | 2 to 4.5 amps | 5 to 7 amps | 5.5 to 8 amps |
| 1 kw 60 cycle | 1.5 to 3 amps | 5 to 7 amps. | |
| 1/2 Kw 120 cycle | 1.5 to 3 amps | 5 to 7 amps | |
| 2 kw 240 cycle | 1.5 to 3 amps | 5.5 to 8 amps | |
| 1/4 kw 500 cycle | 1 to 2 amps | 3 to 4 amps |
Contributors:1) Steve Rosenfeld <oceangate(at)comcast.net>
2) Finding Aid http://hdl.library.upenn.edu/1017/d/pacscl/HML_246483
3) Infoage Science and History Centre https://infoage.org/