OK this was a surprise for me...and my apologies if this beacon is already well-known, or if this is not the correct forum. But is is an HF beacon, and is not sending an FCC-licensed callsign - so it is an 'unlicensed HF beacon'... but one that is not exactly clandestine either.
This CW beacon is on 28.570 MHz and sends telemetry data that includes (as near as I can decipher) local temperature, humidity, AC mains voltages, plus a few other pieces of data/readings that are more obscure. The beacon can *only* be heard on the Utah SDR (by design I'm sure), and probably is very low power - a few milliwatts. Its purpose seems to be to facilitate remote monitoring of the local environmental and electrical conditions at the Utah SDR site by simply tuning into the web-based SDR. Very clever! Here's what was being sent at 0300 UTC:
VVV VVV VVV (x3) DE UTAHSDR
TMP F 47 32 57
HUM 28 25 47
VAC 123.8 121.1 125.9
LCT 0
HCT 0
PF DUR0/0SEC AGO
The TMP and HUM numbers are likely temp and humidity readings. The 3 numbers are for current, low and high readings respectively?
VAC also has 3 numbers and all are in the 120 range. They are probably for the AC mains voltage - again current, low and high readings like the temp & humidity.
Just what the LCT, HCT and PF numbers represent are still a mystery.
STENDEC