Bill,
I wrote on this list a discussion and some options on this topic. I received feedback from some of the readers but none from yourself or Joe and the team. Did you receive it? I explained why the original proposals were less than ideal and offered a reasoned argument for alternatives. Feedback on the initial thoughts was received and a further revision offered..... The summary version of my recommendations therefore are: 3.565, 7.065, 14.065, 21.065 and 28.065 This meets the following criteria: 1. provides separation between RTTY and FT4 contesters when they are running simultaneously (RTTY runs above the FT8/JT9 segments currently) 2. avoids/limits impact on known QRP CW centres of activity 3. avoids impact on the PSK community on .070-.074 4. avoids pushing digital modes far into the voice segment of the bands particularly on 80/20m but is a major compromise on 40m. 40m's digital modes segments are a mess anyway and harmonisation is difficult at best on that band. From a global SSB usage perspective 7.065 should offer a reduced impact compared to moving above 7.080MHz and for all but CQ WW and CQ WPX RTTY most RTTY contests stick to 7030-7060 today. These are admittedly outside current digital segments in all cases. That didn't seen to be a consideration of the original proposals either so no net gain or loss in that regard. As far as actual band usage goes, these suggestions probably offer long term a lower impact outcome than what the FT8 team originally proposed IMHO. Of the original proposals, I offered the following observations in support of the above arguments: 1. 80m - 3595kHz USB proposed frequency was outside the JA 80m band and would interfere with the IARU R3 emergency comms Centre of Activity on 3600kHz LSB 2. 40m - 7090kHz USB - way outside the digital modes segment for everywhere but North America. Impacts SSB voice operators in Region 1 and 3. Will not be well received 3. 20m - 14140kHz USB - again way outside the digital modes segment. I presume it was intended to get above the bulk of the RTTY operators in a RTTY contest. There is no guarantee of that happening however. A better outcome would be to move below the current fixed digital mode transmissions below 14.070 and provide complete separation of FT4 from RTTY during a digital contest. 4. 15m - 21140kHz - actually might have been OK - but after the discussion on the other bands, if a convention of using .x65 can be established then it would help operator memory. 5. 10m - 21180kHz - same argument as 15m 6. WRC Bands - if the mode is intended for contesting then based on the IARU global agreement to not hold contests on WRC bands, not allocating frequencies on 30/17/12m for a mode with "Contesting" in its DNA is a good thing. If FT4 starts to take over from FT8 or FT8 F/H mode for general DXing, then come back and revisit frequency allocations on those bands. However, as your stated objective is to start with FT4 as a CONTESTING mode, don't offer WRC band frequencies. Your thoughts please? Regards, Grant VK5GR From: Bill Somerville [mailto:[email protected]] Sent: Monday, 29 April 2019 1:22 AM To: [email protected] Subject: Re: [wsjt-devel] FT4 Frequencies On 28/04/2019 16:07, Richard Solomon wrote: Since roll-out is imminent, have we an agreement on which frequencies to use ? 73, Dick, W1KSZ Hi Dick, not yet. There are many claims on the frequencies we have proposed, a few with suggested alternatives but mostly just asking us to go elsewhere. Getting to an acceptable set of suggested frequencies for FT4 even for occasional contest periods is difficult and it is made even harder if we assume, not unreasonably, that FT4 may be used for general DXing as well. One option is not to recommend any frequencies and let the community sort it out, then add the resulting frequencies to the default recommendations later as/if they converge. Unfortunately I don't think that will achieve the desirable global coordination, nor is it likely to converge on the best choices. The only good attribute would be that the developers can say "we didn't choose that frequency, don't blame us for QRM" which is a bit of a cop out, and we will still be blamed anyway. Another option is to sacrifice the JT9 slots in favour of FT4. Clearly that is not straightforward given that JS8CALL has made a claim on that bandwidth too. Personally I would love to see JT9 get more use, it is a great mode for HF and I miss working the world with a few mW on the HF bands. Given the lack of truly free globally available slots in the narrow band digital mode band plans, I suspect that no more than one 2 kHz slot per band for FT4 should be an aim. By that I mean that if there is a contest using FT4 then it should use those frequencies and non-contest participants should defer. This is based on the premiss that FT4 has been designed with contests in mind. This would need somewhat smarter logic in WSJT-X to try and avoid chaos when non-contest participants inadvertently get involved in contest QSOs. Of course each contest's organizers can elect to suggest different slots which may be acceptable if the traffic volumes are low enough. Suggestions are still welcome, nothing is set in stone just yet. 73 Bill G4WJS.
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