[Milsurplus] VLF radio frequencies

[Hubert Miller]

Thanks, Dave. So no, I was not imagining it. Years back, in the early 1980s, I would hear that sound on telephone voice circuits from Seattle to the Olympic Peninsula.
And yes, I'm aware that voice circuits were muxed up to higher data rates, digital, to get out there, but there were still long wire stretches in those remote areas, and this
sound is in the voice range.

Also, I used to work a graveyard shift and drive to Bellevue WA from Woodinville WA, about 30 minutes. I would be listening to some weaker AM station as I drove, not
one of the powerhouse 50 kWs.  At a certain low spot in the road, somewhere near Woodinville, the broadcast station would bottom out in strength, and I would hear this
TTY sound. Oso WA station NLK is only 60 something miles north of there.
-Hue
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