V21.63 2018 January 2022
Added two proof-of-concept options to show how pseudo-random
(repeatable) numbers/serials might look & feel in operation.
The options provide for 3 or 4-digit numbers generated using
calculations based on the callsign and number sent in the
previous QSO. This approach means that previously logged calls
or "serials sent" cannot be changed without being flagged as
an error by adjudication software using the same calculations.
This method of number generation was originally tested and
verified in the UKEICC 80m Random Number contests in 2017 -
ukeicc.com. It is independent of programming languages and
independent of computer platforms.
Some contests have scoring based partly or entirely on known
attributes (country and zone) of the callsign alone - to the
extent that the exchange may be partly or fully redundant.
Some others, for example CWops, have fixed exchanges, perhaps
Membership Number and Name. For these, call history files
pre-fill the exchange, reducing the contests to call-copying
events. The entire exchange is typically sent at high-speed
because it's essentially redundant.
It seems pointless (to me) for contest rules to require the
on-air exchange of redundant exchange elements, incuding our
old "friend" 59(9). This resistance to change dates back
some 35 years or more, to the days before logging software.
Pseudo-random numbers have the potential to reduce the
incidence of redundant exchange elements, and to force
contesters to copy something in adddition to calls. They
can not be "corrected" or determined from subsequent QSOs
without collusion or having sight of other logs concerned.
The RANDOM command is a new feature for all contests with
serials, giving users the choice of 3 or 4-digit pseudo-
random serials. A zero parameter restores sequential
serials. The default when starting a new log, or loading
existing logs, is sequential serials - based on the
previous serial sent. A reminder that SD's SERIAL command
resets sequential serials to whatever initial value you
I intend to experiment with the RANDOM command in future
contests with serials. I hope you will join me.
SD is free from www.ei5di.com
When replacing an older version of SD, take care to "untick"
the box corresponding to "Create a desktop icon" during the
installation process. Otherwise you may have to resize SD's
window, and set other parameters as described in GETTING STARTED
on page 3 of the manual SD.PDF.
In any case, these parameter must be set if you are running
Windows 11 and SD's display does not look like this -
Before any CW contest, check the Function Key memory playback,
and edit the parameters as necessary - it's not automatic for each
contest. Use Shift-F1, F2 as appropriate to edit the parameters.
If you find bugs in V21.63, report them to sd-user (at)
Send your suggestions, comments, or questions to sd-user (at)
contesting.com - not to me directly.
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