* Spec: SO2R with two radios in one instance (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Plan: SO2R implementation (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Move the rotator command rules into RotatorControl (#46) Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com> * Store the SO2R switch, the second Win-Test station and rotator 2 (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Route frequency reports to radio 1 or 2 (#46) Add the RadioSlot enum (FIRST, SECOND) with its QRG and QTF targets, and the pure RadioSlotRouter that decides per RadioInfo packet and per Win-Test station which radio a report belongs to. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Send RadioInfo of radio 2 to SECONDQRG when SO2R is on (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Send Win-Test STATUS of the second station to SECONDQRG when SO2R is on (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Run a second PSTRotator for radio 2 with SO2R (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Start rotator 2 only while an ON4KST session runs (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Settings for SO2R, the second Win-Test station and rotator 2 (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Turn antenna 2 and show QTF2 with SO2R (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Make the SO2R switches observable so Apply shows them (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Document SO2R (#46) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Refuse clashing PSTRotator ports in both directions (#46) Writing either port now checks same-or-adjacent against the drafted value of the other; rotor 1 is only checked while SO2R and rotor 2 are on. Also fixes a misplaced Javadoc, stale WinTest parseStatus Javadoc, docs wording and removes an unused import and dead comment. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Remove the executed SO2R plan (#46) The plan's content lives on in the commits, the spec and PROJECT_CONTEXT. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 5.5 <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)