Hello Bob and everyone else participating in this post mortem....
All of Bob's points are well taken, but I want to reply to 2) and to 5).
REGARDING 2)--Several ops have mentioned that they saw signals that
"popped up" and then disappeared forever after one or maybe two
sequences. There have been two main thoughts on this. First was that
this was just the way the band was on that day. Second was that we were
seeing meteor bursts. Both of those are quite possible and reasonable.
What threw me off was that I did not hear anything that sounded like
meteors....certainly not a lot of it. I saw signals in the waterfall
that were quite strong and would have been easily workable if they had
been EME signals. Then the next sequence, nothing. To me that was
quite strange.
Bob's characterization of the strong signals that would not decode was
right on. I saw signals on the waterfall that were obviously strong,
yet they did not decode. Then I would get a decode of a signal that I
could just barely see. Someone sent me an email privately that said
that FT8 does not decode unless it gets a "full sequence" of data. That
certainly seems like what was happening on Sat. I need some help with
that too. When should we expect to get a decode?
REGARDING 5)I knew that the EU operators did not use the contest mode.
I did not know why(I still don't). I read and reread Bob's statement
about the "reciprocal grid kludge". I am going to need some serious
help trying to understand that. Also, I did not understand that there
are now more programs that have stolen Joe's FB ideas, work, and
sometimes code to produce "bastardized versions" that are once again,
incompatible with WSJT-X. OH, I am sorry, those are called "derivative
works".
I do not know what the exchange is for an EU contest. Someone help me
please. We did not hear a single EU station on 6M....but others might
have.
FINAL THOUGHTS--In the VHF world, what we exchange is GRIDS, even in
casual operating. We need to "educate" the newbies and HFers that grids
are what we need, especially in contests where that is the exchange.
I hope everyone had a good contest in spite of the (slight)
difficulties. Now, the CQ WW VHF contest is coming up, July 21st and
22nd. I hope to see you all there....
73 Marshall K5QE
On 6/13/2018 12:00 PM, k2drh@frontiernet.net wrote:
I'm gonna try one more time -- even in plain text mode it didn't pick up the
carriage returns arrgh_____Hopefully this will be less jumbled all together and be
more readable
-------
Very well written and thought out Marshall. Thanks for that and for opening the discussion of
FT8 use during a VHF contest. With a Flex 6700 I run a separate panadapter and RX slices that
monitor both MSK144 and FT8 all the time with multiple instances of WSJT-X decoding
them. Here are some thoughts, experiences and maybe some different perspectives for
further discussion.
------
1.There is no doubt of the value of having this tool for when the band is “closed” to CW/SSB
or at least unavailable for most stations (i.e. without large antenna arrays). It definitely takes
advantage of marginal Es conditions and short bubbles like no other can. ------
2.It is however most useful for signals that are steady or slowly fading up and down. It becomes upset
and will not decode when there are sudden changes like meteor pings, doppler, rapid fading from ionoscatter,
multipath and a host of other propagation anomalies often found on 6M. As such it can be very
frustrating causing traces to appear and disappear with few if any decodes. I believe some of these
anomalies are responsible for the “one and done” type decodes we often get.
-----
3. The Contest Mode needs to be better documented in the manual. It may be
obvious to us but the checkbox for contest 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 in the FT8 section of the manual nor is it mentioned
in the section that discusses these features.
-------
4.There is a pop up prompt that asks you if you should be in contest mode when you are in the “normal” report mode and receive a “funny number” grid. If you say yes it will put you in contest mode for that QSO and advance normally, but it will revert back for the next one. I’m not sure why stations just don’t say yes or just fail open on this. Maybe they just don’t understand what it means. I suspect since the program can detect this it could be made to “force” contest mode, but the developers apparently decided not to do that.
-----
5.VHF Contest mode is NOT used in Europe only NA. The manual says in section 17 that it should not be used when there is international DX involved and its due to the due the reciprocal grid square kludge they had to use to make contest mode work (it was an afterthought). Using contest mode all the time on 6M and above could really mess up working DX. Worse there are Eurocentric knockoff programs that also decode FT8 like FTDX that don’t even HAVE contest mode since it is of no use to Europeans or HF stations. Apparently a lot of domestic stations are using these knockoffs.
-----
6.Unlike Marshall’s crew some stations continue to call on FT8 even when the band is open. This is not productive. Crowding of several strong signals into one RX bandwidth will cause most receivers to overload and WSJT to fail to decode all the signals in the passband.
-----
7.Not sure why some seem to insist that you reply on their offset but I saw that too. It’s actually
better not to since if several stations reply at once they will QRM each other. The program will actually
stop you from TXing if it sees you on the same offset when it decodes another station working him.
Section 7 of this operating guide addresses this.
https://www.physics.princeton.edu/pulsar/K1JT/FT8_Operating_Tips.pdf
----
8.Rovers do have difficulty using /R. Right now it can be ambiguous who the rover is calling/working. Receiving some TX messages from a rover now can make the auto sequencing advance on stations that are NOT working the rover. Some ambiguity can be alieved by changing the Settings for type 2 compound call holders from the default of Full Call in TX3 to Full Call in TX1.
------
9.Most of the /R problem could be eliminated by making the /R a Type 1 suffix in the software so the /R is only
used in TX1 and TX6 which should be sufficient since in contest mode it normally skips over TX2 anyway (unless of
course you double click TX1 and make the program shortcut right to TX2 which would not have the /R appended
– nothing is perfect sigh) . I think we should petition the developers to make this change.
You’d have to be sharp enough to catch the /R in any case (but you should be OPERATING anyway, not in drone
mode like so many seem to be).
----
10.My pet peeve is that once stations go to FT8 they don’t bother to tune 2M or 6M analog for CQs or CQ there anymore. Unlike Marshall who has much less activity on 2M and above in his part of the country I see lots of locals with 2, 3 or more bands CQ all day on 6M FT8 and its difficult to pry them away from their computer 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 this behavior. The ARRL thumping the drum about the wonders of FT8 in a VHF contest without going into the problems we all saw (see the latest contest newsletter) isn’t helping much either.
----
11.There are ways to get stations to QSY to 2M in the 13 character TX5 free message but
it’s hard and takes up a lot of time. I tried a few different ones:
---- a. 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 a free message back that said “Where?” or “Freq?” and took a lot of time. Am I wrong or do we have a
CALL frequency on 2M where you can CALL another station? Seemed obvious to me but …
-----
b. Sending QSY 144xxx was also inefficient and wasted time while it was
processed (who, me?). I also kept hoping that maybe multiple locals would see
it and try to make a few more Qs too, but I guess it never occurred to them to
try.
-----
c. Sending WB#nnn 144210 (also 13) worked the best since the other guy sees his call in RED in the
windows, knows it’s for him, knows where and can respond yea or nay – best
response being K2DRH QSY or K2DRH 2M or even K2DRH NO 2M since it directs it at me. Still takes a
while though.
----
12. On ON4KST the 205 Group in the mornings we have been very successful using FT8 on 2M 144.174 for 300-500 mile and even longer contacts. Sometime there are several stations on at once. I saw none of this going on during the contest. This has some real potential.------
Well I guess that’s my 12 step program for FT8 operating. Your mileage may
vary.
------
73 de Bob K2DRH
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