[Project] 45 Years in the Making: Urban RF Analysis, 8-node PlutoSDR Array, and "Melodic" Signal Reporting (Solo-developed)
Hi everyone, I’m E25VBE from Bangkok, Thailand.
In 1980, I was 10 years old, dreaming of computers controlling antennas. Today, at 56, I’m closing the loop by merging 45 years of programming evolution with professional-grade RF engineering.
1. The Prediction: DADA1 v3.3 My high-res urban terrain analysis tool. It queries OpenStreetMap for building heights and uses ITU-R P.526 models to calculate diffraction through the concrete jungle of Bangkok. It evolved from Foxbase (2009) to VB.NET to Modern HTML/JS.
2. Engineering Grit: The SDR# Plugin Nothing was "plug-and-play." I spent 3–4 hours daily for 6 months reverse-engineering SDR# to extract VisualSNR and FFT Bins. This grit led to the E24CY Signal Monitor, providing real-time SNR, Bandwidth, and Frequency Deviation reports for our local community.
3. Tapping the Classics: Analog meets Digital I am currently "hardware tapping" IF/RX signals directly from my collection of legacy rigs—including the Icom IC-275, IC-229, IC-2200, IC-2300, IC-V82T, ID-51 and Yaesu FT-212RH, FT-857D—into USB RTL-SDR V3 dongles. My goal is to port my monitor logic to SDR++ on Android, allowing every ham to contribute to a live, community-driven RF Dashboard & Heatmap using smartphone GPS.
4. Automation and Visualization: The "Jojo's Best" Experience
- Rotator Control (DADA2 (Deployment Automation), 3(Digitally Aimed): My modified Kenpro KR-1000SDX is now automated via a BLE 4-relay board, calibrated using a HackRF R10 C2 Mayhem H4.
- Real-time Antenna Visualizer: I’ve also built a 12-node RTL-SDR array that renders live antenna radiation patterns, allowing us to "see" the energy flow in real-time.
- Melodic Roger Beep: A melodic scale helps mobile operators hear their signal quality instantly:
- 1 Beep (Do-Re-Mi-Fa-So): 30–46 dB SNR
- 2 Beeps (Do-Re-Mi-Fa-Sol): 46–56 dB SNR
- 3 Beeps (Do-Re-Mi-Fa-So): 56–76 dB SNR
- Long Beep (Do-Re-Mi-Fa-So): 76–80 dB SNR
5. The Infrastructure (Validation): I verify everything with a professional lab environment:
- Timing: 5x GPSDOs (1 ppb stability) for absolute synchronization.
- SDR Fleet: 8x PlutoSDRs (upgraded with Zynq 7020 FPGAs) for TDoA-based SAR Operations.
- Analyzers: Calibrated using Anritsu MS2711E Spectrum Masters with High Accuracy, Tracking Gen and AM/FM/PM Analyzer.
6. The Mission: This solo, self-funded journey supports Search and Rescue (SAR) Operations under the National Emergency Communication Network (Ministry of Digital Economy, Thailand).
This is a solo, self-funded journey. Purely for the love of the hobby.
- Live Tool:http://dada1.decem.co.th/33.html
- Real-time Signal Monitor Dashboard:http://e24cy.decem.co.th
- GitHub:https://github.com/jojopat/DADA1
"A legend that has been simmering for 45 years, finally getting ready at age 56."
73 de E25VBE 🇹🇭
Posted Mar 5, 2026, 4:52 PM UTC