This morning I’ve spot « K4MT/NT9P » net on 14978 cf (0806z) then I follow their QSY to 9300 cf.. They were active for some time on this frequency with a none-standard « wake-up » FSK sequence (50/500).
But, some minutes later, the wide russian 4-FSK (150/12000) net came on frequency with 2 odd setting variants, was it a coincidence ?
Some screenshots of the wide 4FSK variants:
order: carrier (9300kHz) >> usual 4-FSK 150Bd/4000Hz >> odd status >> usual 4-FSK
zoom on the odd status
They came a bit later with a narrow 4-FSK:
SA measured it at 24.9Bd with a shift of ~666.82Hz and it shows a BW of 2000Hz
I assume it is 4-FSK 25Bd with 666.67Hz shift because:
standard baudrate 150Bd / 6 = 25Bd
standard shift 4000Hz / 6 = 666.67Hz
standard bw 12000Hz / 6 = 2000Hz
The factor 6 on the original waveform seems plausible.
And now the screenshots of K4MT/NT9P session:
2 synched signals of the known K4MT/NT9P « wakeup » sequence (FSK 50/500)
upper one is the one spot today, showing a narrow 25Bd fsk with a shift of 83.4Hz !?
lower one is their standard 50/500 fsk
OH OH wait! wait!
standard shift 500Hz / 6 = 83.4Hz !
Again that factor 6 !
Zoom of the switch part, just to confirm that the content is the same on both mode settings (but was reverted in that case)
I’m not 100% sure both nets are related, as we don’t know a lot of things about the wide 4-FSK net, except it runs some fixed skeds, it has sometimes multiple streams at same time on different frequencies and it’s a long long long time active net (many decades on HF). K4MT/NT9P a short name to describe the net, has been rarely spot using skeds, but still has, it’s a bit obscure net too, running full duplex, sending what I call a « wakeup » sequence for some minutes, sending 5FGs in Baudot with a text separator each 50 groups when linked, also using CW for operator chat coordination purpose.
It would be a good point if we are now capable to say both net are 1 unique net ?
Note: 9300kHz is already a known freq see: