Rsclub2_2andClaude Opus 5.5
4679c708bc
* fix: let ReadUDPbyUCXMessageThread own its DatagramSocket so interrupt() closes it (#115) The field `socket` was a java.net.Socket that was never assigned; the real DatagramSocket lived in a local variable of run(). interrupt() therefore closed nothing and terminateConnection() would have thrown a NullPointerException. The receive loop kept running in two-second timeout steps until the user-disconnect flag was set. The field is now the DatagramSocket, run() binds it when no pre-bound socket was handed in, the loop ends on the interrupt flag or a closed socket, and both interrupt() and terminateConnection() are null-safe. A package-private constructor accepts a pre-bound socket so loopback tests can listen on an ephemeral port; the public constructor used by ChatController is unchanged. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> * fix: stop ReadUDPbyUCXMessageThread truncating datagrams after a short packet (#115) A DatagramPacket keeps the length of the last datagram it received, so a long RadioInfo packet following a short one was cut to the short one's length and failed to parse. The length is reset to the buffer size before every receive, the same way ReadUDPByWintestThread does it. The loopback test sends a short and then a long packet on port 0 and checks that both frequencies arrive. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> * fix: give PstRotatorClient's port constructor a callback, decode AirScout as UTF-8 (#115) The explicit-port constructor left the thread-status callback null, so start() and the first received packet threw an NPE; the default constructor now delegates to it. The AirScout listener decoded replies with the platform charset although the inquirer sends UTF-8. PROJECT_CONTEXT listed PSTRotator as TCP; the client speaks UDP. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix: decode UCX datagrams as UTF-8 and tighten the interrupt test (#115) Review follow-up. UCXLog sends UTF-8 XML, but the listener decoded with the platform charset before handing a String to the parser, so the XML header's encoding was ignored. The port-in-use fallback now sets its receive timeout before the first receive(). The interrupt test waits 1 s, below the 2 s receive timeout, so it fails if interrupt() stops closing the socket; the QRG latches now count one value each. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
KST4Contest
KST4Contest is a Java-based client for the ON4KST chat, developed for coordinated VHF, UHF and microwave contest operation.
The application is developed by Marc Fröhlich (DO5AMF) and since 2026 Philipp Wagner (DN9APW).
Start here
- Project website
- Download Stable, Beta and Nightly builds
- Online manual
- GitHub wiki
- Issues and bug reports
- Development roadmap
What KST4Contest does
KST4Contest combines the ON4KST chat with information that is useful when coordinating contacts during a contest.
Among other things, it can:
- display and filter stations from the supported ON4KST chat categories;
- derive band and frequency information from chat messages and station names;
- maintain Worked and NOT QRV information for the available bands;
- calculate station priorities from distance, activity and other available information;
- manage internal skeds and received Win-Test skeds;
- use AirScout information when evaluating possible aircraft-scatter contacts;
- display stations, paths and additional propagation information on maps;
- exchange information with supported logging programs, Win-Test, PSTRotator and a local DX Cluster interface;
- provide configurable automatic replies for recurring chat requests.
Calculated scores, aircraft-scatter information and path assessments are operating aids. They depend on the available data and should not be treated as guarantees that a contact is possible.
Installation
Ready-to-use packages are available for Windows, Linux and macOS. These packages include the required Java runtime, so a separate Java installation is normally not necessary.
Use the central download page to select the appropriate build:
- Stable is intended for normal contest operation.
- Beta contains changes that are being prepared for a stable release.
- Nightly contains the latest automated development build and is mainly intended for testing.
Documentation
The documentation is available in German and English:
The Markdown sources used for the wiki and the generated PDF manuals are stored in github_docs.
Changes to operating behaviour should be documented together with their purpose and limitations. This is especially important for functions whose result depends on external data, heuristics or information derived from chat messages.
Building from source
Building KST4Contest requires JDK 21. The Gradle Wrapper included in the repository should be used, so a separate Gradle installation is not required.
Linux and macOS:
./gradlew clean build
Windows:
.\gradlew.bat clean build
Repository structure
core/– domain, controller and network code, free of user-interface technologyapp-desktop/– the Compose Multiplatform user interface and the packaging tasksgithub_docs/– German and English manual sourceswebsite/– project website sourcespackaging/– platform-specific packaging files
CI status
Documentation
Builds
License
KST4Contest is distributed under the GNU General Public License v3.0.
Supporters/Sponsor
This Project is possible due to donations of the community.
You can sponsor KST4Contest here: Support on Ko-Fi. If you add an Display Name there you will be mentioned here.
The following people are sponsoring KST4Contest:
- Marco (DJ5KW)