I recently started an open-hardware project based on my RF work for the past several years. Although I was targeting challenging real-time data collection in a tree-fruit orchard envrionment, UAV telemetry seems like a very good match for the design due to the inherent attributes of Low-latency and High reliability. This modem is very similar to the performance characteristics of something like the original MHX910 from Microhard Systems. Let me know what you think.
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Project Development Site For Valhalla Wireless OpenFHSS. OpenFHSS is a community-based effort that includes schematic, eagle design files, BOM, gerbers, and firmware for a 902-928MHz ISM, 50-channel, FHSS frequency hopping spread spectrum modem.