[Lowfer] RTTY question

[Garry Hess]

JB,

According to http://www.jproc.ca/rrp/bey1960.html CFH is no longer 
active on 4271 kHz. However, RTTY transmissions are being simulcast at 
the moment on 10945 and 15920 kHz. Presumably 5097 kHz is also active 
but I hear nothing there currently. Perhaps other frequencies I haven't 
tuned are active as well.

The transmissions are made at 75 baud with 850 Hz shift. This is not a 
decoding offered by MultiPSK as far as I can tell (it provides for 75 
baud but not 850 Hz shift - that's only offered at 45 baud, at least 
with version 4.16. Other RTTY decoding software I have is focused on 
amateur operation and doesn't provide that flexibility either. An 
exception I have is MixW2 but no doubt others are up to the task as well.

The idling message today is: NAWS DE CFH ZKR F1 2822 3394 4158 6242 8324 
12371 16552 AR. In addition to setting the baud rate and shift, make 
sure USOS (unshift on space) is not selected, and if you're tuning with 
USB check the invert option. I use USB centered 1 kHz below the source 
frequency so that means, for example, I tune to 10944 kHz and specify 
1000 Hz as the receive audio center frequency. Then the mark/space tones 
come out at 1 kHz +/- 850/2 Hz. Make sure your receiver filtering 
doesn't clip the signal. I use an SDR-IQ and when it was set up to pass 
500-1500 Hz the decoding was erratic for that reason. Expanding the 
baseband filter to 0-2000 kHz allowed consistent decoding. I'll send a 
screen capture to you direct as it isn't readible when compressed to 
under 35 kB.

73, Garry, K3SIW, EN52ta, Elgin, IL