Mois : novembre 2015

yet another oddity from the Russians (FSK reversals)

Again, the Russians were active on HF using an unknown & weird waveform
That time it’s only FSK reversals with uncommon settings (I’ve measured 16.1Bd with a 1000Hz shift, sent with an offset AF +1500Hz)

2 cycles were identified on 31 october 2015 (confirmed 1 week later, 7 nov 2015), as sked, every 5 minutes and TX lasts for exactly 3 minutes (time in UTC, frequencies in USB):

The TX had spurious images on each sides of its main frequency, as seen on the DIGIMODE experiments recently spotted (, which suggests a relation between the 2 activities



The Russian experiments (HF digimode)

The Russians (prob INTEL) are back into DIGIMODE experiments on last days..

That waveform has been spotted on (at least) 5 frequencies in 2 days, 30 & 31 october 2015
short description of the waveform : 5x mFSK-16 (br:20Bd sh:20Hz) w/ short 250Bd BPSK breaks every 10 secs (carrier changes from 2250Hz to 1000Hz, randomely?) + 1750/1500 tone sequence as EOT
PS: the EOT tone sequence is the same heard on other Russian digimode experiments

That modem trials were already active in 2013 and I’ve made a video of it in the past: