Three new fleet broadcast channels

Three new fleet broadcast channels spotted in these days, all STANAG-4481F:  

4987.0 KHz (cf) 50Bd from NSS Davidsonville
7455,5 KHz (cf) 75Bd from NSY Niscemi
7457.0 KHz (cf) 50Bd from NAU Isabela

All the the broadcast are KW-46 secured(!), although 75Bd/850 usually run KIV-7/KG-84 devices.

These and other recent catches seem to confirm a change in some transmission frequencies, mostly of 2000 Hz or , even stranger, of 1300 Hz. "There is currently a Navy exercise in progress off the east coast, so the shift may perhaps be supporting that effort or maybe to avoid interference or harmonics on other services at the sites", my friend Mike mco say.

I have updated the page related to the BRASS STANAG-4481F page, it is even more evident that all the transmissions that use the waveform 50Bd / 850 are protected with KW-46.

https://disk.yandex.com/d/XJVGUnkI4D4etg