[Skimmertalk] Notching out FT8 frequencies to reduce CPU load of RTTYSkimServ

[Bob Wilson, N6TV]

Clicking on the "Band scope" button in RTTY Skimmer Server reveals that
RTTY Skimmer creates a *lot* of "decoders" (yellow dots) as it attempts to
identify and process signals that it cannot possibly deal with.  This
wastes a lot of the CPU time.

To reduce the CPU load, I changed the RTTYSegment section of my
RTTYSkimServ.ini file to ignore most of the known FT8 frequencies between
80m and 15m where most of the activity seems to be (at present):

RttySegments=1800000-1820000,3520000-3571000,3577000-3600000,5330000-5407000,7020000-7071000,7077000-7100000,10130000-10132000,10139000-10150000,14060000-14071000,14077000-14150000,18109000-18115000,21060000-21071000,21077000-21150000,24910000-24930000,28060000-28150000,50250000-54000000

(Of course this statement must be on a  *single long line*; email programs
may show this statement as multiple lines due to line wrap).

The reduction in CPU utilization was immediate and noticeable.  My i7-7700
PC has a variable speed cooling fan, the higher the CPU utilization, the
louder the fan.  It's much quieter now, and I'm still decoding RTTY spots
just fine.

I'm not sure if I should remove these FT8 frequencies during RTTY contest
weekends.  Last time I checked, the FT8 guys were still going strong with
little if any RTTY contest activity in the FT8 frequencies, but I haven't
tried to analyze the raw data files to see how many RTTY spots were posted
to these FT8 frequencies that I'm now ignoring.

73,
Bob, N6TV