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

[Ron Castro]

Bob:  What should the center frequencies be set for?

          Ron Castro
           N6IE
    www.N6IE.com

Member:
                  ARRL
     Redwood Empire DX Assn.
Northern California Contest Club
Northern California DX Foundation
  Society of Broadcast Engineers

-----Original Message-----
From: Skimmertalk <skimmertalk-bounces at contesting.com> On Behalf Of Bob
Wilson, N6TV
Sent: Friday, June 15, 2018 3:30 PM
To: SkimmerTalk Reflector <skimmertalk at contesting.com>
Subject: [Skimmertalk] Notching out FT8 frequencies to reduce CPU load of
RTTYSkimServ

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
,7020000-7071000,7077000-7100000,10130000-10132000,10139000-10150000,1406000
0-14071000,14077000-14150000,18109000-18115000,21060000-21071000,21077000-21
150000,24910000-24930000,28060000-28150000,50250000-54000000

(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
_______________________________________________
Skimmertalk mailing list
Skimmertalk at contesting.com
http://lists.contesting.com/mailman/listinfo/skimmertalk