[VHFcontesting] FT8 and the ARRL June VHF Contest

k2drh at frontiernet.net k2drh at frontiernet.net
Wed Jun 13 12:23:04 EDT 2018


  Very well written and thought out Marshall.  Thanks for that and for opening thediscussion of FT8 use during a VHF contest.  With a Flex 6700 I run a separate panadapter andRX slices that monitor both MSK144 and FT8 all the time with multiple instancesof WSJT-X decoding them.   Here are some thoughts, experiences and maybe somedifferent perspectives for further discussion.   
   - There is no doubt of the value of having thistool for when the band is “closed” to CW/SSB or at least unavailable for moststations (i.e. without large antenna arrays).  It definitely takes advantage of marginal Es conditionsand short bubbles like no other can.   
   - It is however most useful for signals that aresteady or slowly fading up and down.  Itbecomes upset and will not decode when there are sudden changes like meteorpings, doppler, rapid fading from ionoscatter, multipath and a host of other propagationanomalies often found on 6M.  As such itcan be very frustrating causing traces to appear and disappear with few if any decodes. I believe some of these anomalies are responsiblefor the “one and done” type decodes we often get. 
   -  TheContest Mode needs to be better documented in the manual.  It may be obvious to us but the checkbox forcontest mode does not even appear in the FT8 window unless you have Enable VHF,UHF and Microwave features checked in the settings. This is not discussed inthe FT8 section of the manual nor is it mentioned in the section that discussesthese features.  
   - There is a pop up prompt that asks you if youshould be in contest mode when you are in the “normal” report mode and receive a“funny number” grid.  If you say yes itwill put you in contest mode for that QSO and advance normally, but it willrevert back for the next one.   I’m not sure why stations just don’t say yesor just fail open on this.  Maybe theyjust don’t understand what it means.  Isuspect since the program can detect this it could be made to “force” contestmode, but the developers apparently decided not to do that. Rather than fightthem I just switch to reports.  No cluewhat to do about going straight to TX2 to answer your CQ.  
   - VHF Contest mode is NOT used in Europe only NA. Themanual says in section 17 that it should not be used when there is internationalDX involved and its due to the due the reciprocal grid square kludge they hadto use to make contest mode work (it was an afterthought).  Using contest mode all the time on 6M andabove could really mess up working DX. Worse there are Eurocentric knockoff programsthat also decode FT8 like FTDX that don’t even HAVE contest mode since it is ofno use to Europeans or HF stations.  Apparently a lot of domestic stations areusing these knockoffs. 
   - Unlike Marshall’s crew and other real contesterssome stations continue to call on FT8 even when the band is open.  This is not productive. Crowding of several strongsignals into one RX bandwidth will cause most receivers to overload and WSJT tofail to decode all the signals in the passband.    
   - Not sure why some seem to insist that you replyonly on their offset but I saw that too. It’s actually better not to since ifseveral stations reply at once they will QRM each other.  The program will actually stop you from TXingif it sees you on the same offset when it decodes another station workinghim.  Section 7 of this operating guide addressesthis.    https://www.physics.princeton.edu/pulsar/K1JT/FT8_Operating_Tips.pdf 
   - Rovers do have difficulty using /R.  Right now it can be ambiguous who the roveris calling/working.  Receiving some TXmessages from a rover now can make the auto sequencing advance on stations thatare NOT working the rover.  Some ambiguitycan be alieved by changing the Settings for type 2 compound call holders fromthe default of Full Call in TX3 to Full Call in TX1.   
   - Most of the /R problem could be eliminated bymaking the /R a Type 1 suffix in the software so the /R is only used in TX1 andTX6 which should be sufficient since in contest mode it normally skips over TX2anyway (unless of course you double click TX1 and make the program shortcutright to TX2 which would  not have the /Rappended – nothing is perfect sigh) .   I think we should petition the developers tomake this change.  You’d have to be sharpenough to catch the /R in any case (but you should be OPERATING anyway, not indrone mode like so many seem to be).  
   - My pet peeve is that once stations go to FT8they don’t bother to tune 2M or 6M analog for CQs or CQ there anymore (see my 3830 rant).  Unlike Marshall who has much less activity on2M and above in his part of the country I see lots of locals with 2, 3 or morebands CQ all day on 6M FT8 and its difficult to pry them away from theircomputer screens to QSY to 2M and work some real radio.  FT8 on 6M seems as addictive as crack.  My 2M and up totals really suffered from thisbehavior.  The ARRL thumping the drumabout the wonders of FT8 in a VHF contest without going into the problems weall saw (see the latest Contest Update Jun 13) isn’t helping much either.  
   - There are ways to get stations to QSY to 2M inthe 13 character TX5 free message but it’s hard and takes up a lot of time.  I tried a few different ones:         
      - Just sending QSY 2M? or even WB#xxx QSY 2M(exactly 13 – spaces count) resulted in fail open most of the time or at best afree message back that said “Where?” or “Freq?” and took a lot of time.  Am I wrong or do we have a CALL frequency on2M where you can CALL another station? Seemed obvious to me but …
      - Sending QSY 144xxx was also inefficient andwasted time while it was processed (who, me?). I also kept hoping that maybe multiplelocals would see it and try to make a few more Qs too, but I guess it never occurredto them to try. 
      - Sending WB#nnn 144210 (also 13) worked the bestsince the other guy sees his call in RED in the windows, knows it’s for him, knowswhere and can respond yea or nay  – best responsebeing K2DRH QSY or K2DRH 2M or even K2DRH NO 2M since it directs it at me.Still takes a while though.    

   -  On ON4KSTthe 205 Group in the mornings we have been very successful using FT8 on 2M 144.174for 300-500 mile and even longer contacts. Sometime there are several stations on at once.  I saw none of this going on during thecontest.  This has some realpotential.  
Well I guess that’s my 12 step program for FT8 VHF contest operating.  Another tool in our arsenal. Your mileage may vary.   73 de Bob2 K2DRH


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