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Author Topic: 11,175 KHz data stream  (Read 765 times)

Offline Teotwaki

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11,175 KHz data stream
« on: July 15, 2019, 0128 UTC »
01:29Z 15July2019

Possibly someone threw the wrong switch?

I heard a few normal USAF voice messages and next thing this odd data signal pops up. Within the USB channel there are three main peaks appearing on my waterfall display

Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

Offline Josh

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Re: 11,175 KHz data stream
« Reply #1 on: July 15, 2019, 1850 UTC »
USAF has a legacy TFSK (triple fsk) mode, can't recall the name, shows up every few months.
I've seen where a naoc flight will be expecting a data sig on hf and hfgcs will provide it, sometimes even on 11175. This is odd because of all the traffic triple one sees, but a general gets what a general wants I suppose. Normally they use a discreet like 11220 or 11244 for such.
« Last Edit: July 16, 2019, 0329 UTC by Josh »
Conveniently located near Vincennes Indiana.