It looks we will only have one more major VHF contest with all the confusion on
FT8 with regard to contest mode and rover procedures. Here is what K1JT posted
to the WSJT Yahoo group yesterday. I suppose there will be some issues with
people with out-of-date software, but the backward-incompatibility will soon
get them to download the new version.
73,
Steve VE3SMA
Hi to all,
Of course we are well aware of the issues many have experienced when
using WSJT modes in North American VHF contests. To summarize, there
are two main problem areas:
- Decoding of messages with two callsigns followed by "R " and a
4-character grid, and the related auto-sequencing, depend of proper
and coordinated setting of a checkbox at both stations.
- There is a crying need for transparent support of "/R" (Rover)
callsigns in all standard messages, during contests.
Here's some background information aimed at relative newcomers and
casual users of WSJT, followed by a brief preview of program features we
plan to make available in Version 2.0 of WSJT-X.
Contest Mode
------------
Standard JT-style messages (those used in all of the structured WSJT
modes) have 71 information bits: two 28-bit callsigns and a 15-bit grid
locator. The 15-bit field can alternatively convey a signal report
(with optional "R"), or "RRR", "RR73", or "73". One additional bit
re-purposes the 71 bits to carry a 13-character free test message. In a
72-bit packet there are NO free bits available to insert "R " before a
grid locator, or "/R" after a callsign.
The "NA VHF Contest" checkbox presently in WSJT-X is a stop-gap feature
added in 2016 to the MSK144 mode, and later to FT8. These modes
conventionally use 15-second T/R intervals and offer semi-automated
message sequencing. NA VHF contests require the exchange of 4-character
grid locators. Signal reports are OK, but not required. Contesters
wanted a way to send messages like "K1ABC W9XYZ R EN37", thereby
increasing their QSO rates by eliminating some transmissions from the
standard minimal-QSO sequence.
Rovers
------
Rovers move from grid to grid and must append "/R" to their callsign
during the contest. These hardworking folks definitely need some help
if they are to use WSJT modes effectively.
All structured modes currently supported in WSJT-X permit messages like
these:
CQ K1ABC/R FN41
DE K1ABC/R 73
... but you can't use a second callsign in place of the "CQ" or "DE".
Once again, there is no room for such information in a 72-bit packet.
Some time ago we created workarounds that enable QSOs using a "/R"
callsign or an "R+grid" message fragment. But these capabilities are
limited and necessarily somewhat clumsy. Users must understand what's
possible and what's not, and they must be careful about some necessary
program settings. Decoding "R+grid" messages requires ticking a
checkbox, and if someone else sends you standard signal reports you need
to uncheck the box or manually edit your messages. Also, for reasons
explained in the WSJT-X User Guide, this feature cannot work well when
world-wide propagation is possible -- as it has been recently on 6 meters.
All in all, it's not a happy situation -- especially when considering
the typical presence of many casual operators who happen upon a contest
and just want to make a few QSOs.
Recently K9AN, G4WJS, and I have been developing enhanced versions of
the MSK144 and FT8 protocols that extend the message payload to 77 bits.
For a taste of what's to come, here's a brief list of things made
possible by the extra bits:
1. NA VHF Contest operation with full support of grid exchanges and
"/R" (Rover) callsigns
2. EU VHF Contest operation with the exchange of 6-digit grids, QSO
serial numbers, and "/P" (portable) callsigns
3. ARRL Field Day operation with standard Field Day exchanges
4. ARRL RTTY Roundup operation with standard contest exchanges
5. Better and more user-friendly support for compound and nonstandard
callsigns
6. A special "telemetry" message format for exchange of arbitrary
information up to 71 bits
7. The existing FT8 DXpedition mode will be supported, and a more
powerful DXpedition mode may be offered as well.
All of these features work seamlessly and automatically. No "contest
mode" checkboxes are needed. In most situations decoding sensitivity
will be slightly better than at present for FT8; for MSK144 it will
sometimes be about 0.5 dB worse. Occupied bandwidths will be the same
as they are now, and false-decode rates will be significantly lower.
Much of the necessary programming is finished. Many of the new features
have been tested on the air, and we find them to work well.
Don't rush to download something -- these capabilities are not yet
publicly available. There is more testing and code optimization to do.
With summer vacation plans, etc., our current plans call for a
beta-testing period probably starting in mid to late September. A full
release should then be possible a couple of months later.
In particular: we are planning to make WSJT-X Version 2.0 available in
time for you to read its new documentation and practice using it before
(for example) the ARRL RTTY Roundup, January 5-6, 2019, and the ARRL VHF
Sweepstakes, January 19-21, 2019.
THIS IS IMPORTANT: The new protocols cannot be backward compatible with
the existing ones. We will probably provide some temporary "bi-lingual"
capability for FT8, but not for MSK144. It will be essential for users
to upgrade to Version 2.0 in order to use the new features and
communicate with others who have made the upgrade.
We will provide plenty of advance notice about a transition interval and
an essential "must upgrade by" date.
-- 73, Joe, K1JT
_______________________________________________
VHFcontesting mailing list
VHFcontesting@contesting.com
http://lists.contesting.com/mailman/listinfo/vhfcontesting
|