T84
A Legend, Reimagined.
Rediscover the instrument that once watched the skies, now rebuilt for a new era of exploration.
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The Silent Guardian: T-84 Radar
Born in the crucible of the Cold War, the T-84 Air Defence Radar was a marvel of mid-20th-century engineering. As a key component of the nation's early warning system, its powerful transmitters and sensitive receivers swept the skies, a silent, vigilant guardian against unseen threats. For decades, it stood as a testament to human ingenuity, its massive array a symbol of both technological ambition and geopolitical tension.
Decommissioned and left to the elements, the T-84's story seemed to have ended. However, its robust construction and foundational design principles held a timeless quality. We saw not a relic, but a foundation. This project is the ambitious undertaking to resurrect this legend, retrofitting its core structure with state-of-the-art autonomous systems, advanced sensor arrays, and a neural network capable of processing data far beyond its original design.
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ARCHIVE FILE: 77-B
Historical Records & Blueprints
[ CLICK TO OPEN ]A Public Challenge
It began with a simple, audacious post on Reddit: “Help, I want to bring this back to life.” The subject was the T-84, a 100-foot, decommissioned Cold War-era radar system. A silent giant left behind by history.
A technology entrepreneur with a lifelong passion for engineering and preservation felt a quiet sadness at the thought of the T-84 slipping further into decay. His goal was never to claim it for himself, but to see if it could be coaxed back to life and to let others share in the story, explore the technology, and play a part in its revival.
The task was formidable. Yet the thinking was clear: even if full restoration proved impossible, the journey could still ignite enough curiosity and passion to keep this piece of history alive for those who once worked there to defend their homeland, and for future generations to understand where we came from. With a deep technical background and access to modern tools, he believed the past might still be within reach.
This website proudly marks the milestones of an extraordinary journey. After two years of relentless planning, precision engineering, and the harnessing of powerful AI, the great antenna stirs once more alive, vigilant, and listening to the skies again.
Gallery
Putting The Legend to the Test
Independent & Unbiased Analysis
A bold claim is one thing; proving it is another. After successfully creating a powerful passive radar system using the original antenna, it was time for the ultimate test. We invited a team of independent experts including ex-military signals specialists, seasoned radio engineers, and telecommunications veterans to our facility at the former RAF Neatishead.
Their mission: to rigorously test, challenge, and validate every aspect of the newly reborn system. They were given full access to scrutinize the hardware, software, and the data we were collecting, ensuring that our claims of performance and capability stood up to real-world, expert analysis.
The Core Innovation
From Theory to Reality
See the system in action, transforming ambient noise into a clear, actionable picture of the skies above.
A Look Under the Hood
This project is built on over 30,000 lines of code. To show this isn't just a concept, here's a simplified look at the high-performance C++ architecture that powers the T-84. This is a glimpse into the complex software that makes our advanced passive radar possible.
1. Time Synchronization via GPSDO
To fuse data from multiple sensors, every signal must be timestamped with nanosecond precision. We achieve this using a GPS-disciplined oscillator (GPSDO), a high-stability clock locked to the atomic clocks in GPS satellites, ensuring every data packet across the network is perfectly aligned in time.
2. Multi-Illuminator Reflection
Instead of relying on a single signal source, the system processes reflections from multiple "illuminators of opportunity" (like various TV and radio towers) at once. This creates a richer, more resilient dataset, allowing for more accurate detections even in noisy signal environments.
3. Advanced Sensor Fusion
Drawing from years of experience in self-driving cars, we apply sophisticated sensor fusion algorithms. An Extended Kalman Filter (EKF) takes the time-synced data from multiple T-84 units and illuminators to produce a single, high-fidelity track for each object, drastically reducing error and improving predictive accuracy.
4. AI-Powered Server & UI
The fused data is sent to a central server where an AI layer performs a final "sanity check." It validates antenna configurations, sync status, and the number of illuminators before serving the data to an incredibly intuitive front-end. This AI ensures data integrity and automatically records high-confidence events that meet our strict detection criteria.
t84_core_processing.cpp
Downloads
After two years of focused research and development, we are pleased to introduce the T-84 passive radar system. Designed in collaboration with industry specialists and refined through advanced AI modelling, the T-84 represents a significant step forward in aerospace surveillance. Using a combination of advanced sensor fusion and object-tracking algorithms, the T-84 can detect and monitor aerial objects, including those without transponders. In testing, the system has achieved an accuracy of 25 metres at distances of up to 250 miles. When multiple SDR's running the same system are networked together, performance is further enhanced, providing broader coverage and greater situational awareness. The full T-84 software suite, along with its individual subsystems, is now available for download. It can run on any SDR and Users can operate the system with their own antenna or connect to a dedicated T-84 antenna for optimal performance
Some aspects of this technology fall under dual-use regulations. In our commitment to openness, while respecting these regulations, we are making different software and data files available at different times. Explore the available modules below.
Press
Request a Demonstration
What began as a passion project has evolved into a surprisingly powerful passive radar system. Its capabilities have attracted interest from research institutions and commercial organizations. We now offer private demonstrations for qualified parties interested in the potential of advanced, cost-effective passive radar technology.
