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Posted by Bruce WA1HGJ on February 18, 2026 at 23:53:10.
In Reply to: Re: 279 Marcy posted by Gedas W8BYA on February 18, 2026 at 07:00:09.
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Hi Gedas, March and all, I may be able to shed light on this. The carrier on 209 kHz is likely from one or both of the NDBs MJ (Manchester, NH) or MT (Chibougamau, QC), both of which I hear here regularly north of Boston. MJ's ID is sent by Morse code with sidebands +/- 1.02 kHz, while MT's ID is by Morse code +/- 0.4 kHz (or maybe only one of those 2 sidebands). I can always hear MJ, and when MT comes in, it's slightly off frequency from MJ so I can hear a 1-2 Hz beat on the tone, that's how I know to listen for the 400 Hz MT ID (drop in a notch filter to blank out the carrier, then the 400 Hz sideband(s) are more audible). There are still a goodly number of NDBs out there---there's a listing of logs in every issue of LOWDOWN--although diminishing regularly, so many of the carriers heard may be NDBs. If you hear a carrier, listen carefully +/- 1 kHz for (mostly) US NDBs and +/- 0.4 kHz for most (but not all) Canadian NDBs. 73, Bruce WA1HGJ
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