A magistral UHF/DMR repeater — with APRS and Meshtastic nodes on the same summit.
At Čemernica, we are building an autonomous radio-communications site combining UHF/DMR repeater infrastructure, APRS, Meshtastic and remote system control — with a power system designed to operate independently of the electrical grid.
1339
Goli Vis · 1339 m n.v.
Outside the Kozara major repeater area, much of the Banja Luka region has historically had weak VHF/UHF amateur-radio coverage. The idea of Čemernica grew from operating on the summit, where club members during VHF contests recognised exceptional propagation and the potential of the site for wider radio infrastructure.
Project path
Six steps from the first concept and regulatory process through the container, fit-out and the first signal from Čemernica.
The idea of new magistral amateur-radio infrastructure began with choosing Čemernica and assessing its potential to cover a wider area.
After the site was chosen, the regulatory and administrative phase followed — obtaining the permits, consents and conditions required to install and operate amateur-radio infrastructure.
After project preparation, work moved onto the summit itself — preparing the terrain and building the foundation for the technical container and future infrastructure.
One of the most important steps in the project. The technical container is the foundation of everything that follows — the shell where the radio infrastructure will live and operate on the summit.
Fitting out the technical container covers power, radio equipment, the control system and the rest of the infrastructure needed for reliable operation at a remote mountain site.
Final installation, interconnection and system checks lead to the moment the project was started for — bringing the infrastructure into service and the first signal from Čemernica.
System on the summit
At Čemernica, radio systems, digital networks, remote control, network infrastructure and autonomous power operate as one whole.
Coverage
Modelled radio-system coverage from the Goli Vis site is shown over real terrain. The display is a propagation estimate, not a measured field-strength survey.
Modelled coverage
Signal
Band labels are a visualisation aid — usable thresholds differ by radio system.
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People behind the system
Čemernica took shape through many kinds of work — from planning and preparing equipment to transport, installation, testing and maintenance on site. Behind the systems stands the shared effort of people who linked knowledge, time and experience into one working whole.
Radio engineering, electronics, networks, power systems and field experience combined into one solution.
Site preparation, transport, installation, interconnection and system checks were done directly on the mountain.
Different people took on different parts of the work, but the result was always shared.
Putting the system on air is not the end of the project — the site needs regular monitoring, service and further development.
Project support
Čemernica was built through the work of club members, and also with the support of people, organisations and companies that helped with equipment, materials, services or funding.
Project status
Čemernica has grown from an idea into working amateur-radio infrastructure. Key systems are in place on the site, but development continues through greater autonomy, additional equipment and better conditions for operating and staying.
Today
The location is equipped as an autonomous amateur-radio point with UHF/DMR infrastructure, APRS and Meshtastic services, network connectivity, off-grid power and remote monitoring and control.
Operational
Magistral UHF/DMR repeater infrastructure for local and regional amateur-radio traffic from the summit.
APRS node for positions, short messages and digital packet traffic over the radio network.
Low-power Meshtastic / LoRa node that extends the site into a decentralised mesh network.
Site networking for services, data exchange and connectivity of systems on the mountain.
Solar 12 V off-grid supply that keeps the site running independently of the electrical grid.
Remote supervision and control of key systems from a distance, without being physically on site.
Up next
Next steps focus on greater autonomy, weather data, a VHF/UHF/SHF beacon, remote amateur-radio operation and better conditions for staying and working on the summit.
Planned
Expanding battery capacity should increase system autonomy and provide safer operation during periods of weaker solar yield.
Internet + APRS
The planned station will track weather conditions on the summit and send data via the internet and through the APRS network.
Remote operation
Adding a dedicated antenna system will make it possible to use the Čemernica station for remote amateur-radio operation from the site.
Further work is planned on the interior space for staying and operating, as well as the immediate area and yard around the facility.
Propagation
A continuous beacon on VHF, UHF and SHF will support propagation monitoring from the summit and let operators check conditions toward Čemernica without needing a two-way contact.
Project diary
Work, testing, upgrades and activity from the site through club updates.
