[CQ-Contest] FT4 and FT8 Contesting

[Ed Muns]

Good comments, Randy.

I've copied the paper's authors because some of them aren't regular
subscribers to this list.  The ideal protocol for QSO completion and logging
differs by contest.  Rather than specify a set of exact protocols covering
all contests, we offered a list of the message content sufficient for a
complete QSO.  It is the same list that top CW, SSB and RTTY operators
recommend.  That is, both QSO partners exchange calls and exchanges plus an
ACK (each) that the information was received.

The paper points out that a third ACK, e.g., '73' sent in response to a
'RR73' is unnecessary.  Nonetheless, some operators, often casual operators,
have come to expect a third ACK (73) is needed for QSO completion.  In those
cases, they often repeat their RR73 message in order to elicit another ACK
(73) from their QSO partner.  An attentive QSO partner will pick up on that
clue and manually send the unnecessary third ACK (73) to maximize
probability that their QSO partner will log the QSO.  This is an example of
operator engagement and dynamic messaging that encourages skill development
in FT contesting.

NILs will never be eliminated, in any mode, because of the imperfect nature
of radio propagation.  Message delivery cannot be guaranteed, no matter how
many ACKs are sent.  Over decades of operation and contesting the NIL rates
for CW, SSB and RTTY have settled in the range of 1-2%.  When a QSO message
is not copied, we ask for fills or repeat our last message.  We've learned
that if our QSO partner starts a new QSO right after we should have received
their last message in our QSO, that that most likely means they logged the
QSO.   Our assumptions will never be 100% right, thus a small NIL rate.
That's reality and what makes operating interesting and not a purely robotic
activity.

Currently, the FT NIL rate is significantly higher than the legacy modes,
4-6%.  The first step of improvement is to reduce it to what the other modes
have shown is feasible.  There will always be the quest for a Golden log,
balanced with speed.

Ed W0YK

-----Original Message-----
From: k5zd at charter.net <k5zd at charter.net> 
Sent: 26 February, 2020 14:05
To: ed at w0yk.com; cq-contest at contesting.com
Subject: RE: [CQ-Contest] FT4 and FT8 Contesting

Excellent summary.  Thanks for all of you to make the effort to look into
the higher than expected NILs in the Digi contests.

I would have preferred to see the analysis go one step further and actually
suggest a protocol for handling end of QSOs.  The FT protocol is fixed, and
the analysis assumes it is up to the operators, but just a bit more
explanation of what people should do/expect would be very helpful for the
community.  Especially those ops that are new to FT contesting.

I am quite sure things will improve as we all gain experience.  I have
learned a lot about how the better manage the QSO process just by doing more
FT operating and really paying attention to the QSO flow and how to handle
the edge cases that happen when you think you finished a QSO, started
another, and then realize partner #1 is still looking for an ack.  All part
of the game I guess!

73

Randy K5ZD


-----Original Message-----
From: CQ-Contest <cq-contest-bounces+k5zd=charter.net at contesting.com> On
Behalf Of Ed Muns
Sent: Wednesday, February 26, 2020 11:51 AM
To: cq-contest at contesting.com
Subject: [CQ-Contest] FT4 and FT8 Contesting

Log checking for several recent contests that used the FT4 and FT8 modes has
shown undesirably large numbers of claimed QSOs that receive not-in-log
("NIL") status from the other station.  The WSJT development team has worked
together with contest sponsors and log checkers to analyze the probable
causes of these NILs.  Our findings and some operating advice for future
contests are posted here:
http://physics.princeton.edu/pulsar/k1jt/FT4_FT8_Contesting.pdf
and will also appear in the May-June 2020 issue of NCJ, the National Contest
Journal.

  	73 from the authors of the study:

	Steve Franke, K9AN
	Don Hill, AA5AU
	Ed Muns, W0YK
	Iztok Saje S52D
	Joe Taylor, K1JT

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