Mois : septembre 2015

19-29 September – HF logs




new? mFSK8 50Bd 110Hz

A new digimode for me, on 6687.0 USB today

Appears to be mFSK8 50Bd with a 110Hz shift
I heard them sending a 8.6sec xmit, then a 15.2sec after a short silence

part #1
part #2

A guess: the lower tone could be like a space or special character/timing delimiter ?…like heard on some « polytone » intel stations..


the Wide 4-FSK net & K4MT/NT9P related ?

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 !

25vs50-zoomedZoom 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:


FUG La Régine (Saissac, FR)

During last summer holidays, I had the opportunity to drive nearby the French Navy HF site named « La Régine »

Here is a far pic of the site, viewed from North, with « Les Pyrénées » mountains in the background

I had bought a HF/RX there so I was able to confirm all those frequencies & modes:

Note: some frequencies of that list are already not active anymore and/or mode has changed between RATT & S4285.. Those guys are working hard on setting up/down datalinks it seems..