Probably the world's best Linux logging program. If you are an active ham using Linux, there is probably nothing even close to CQRLOG. We have almost 3000 registered users all over the world. It can control the radio, integrated support for LoTW, eQSL, can upload your QSO to HamQTH, ClubLog, HRDLog.net, band map, RBN monitor and much more.
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HF propagation to your Linux desktop. It shows propagation data provided by Paul, N0NBH. My small holiday project :).
A UDP server allowing operation of the Winkey USB by K1EL with any Linux program with UDP keyer capability. It works in the same way as the popular CW daemon. With Winkeyer USB server expands the usability of this excellent product to all Linux program with UDP keyer capability (TLF by PA0R etc.)
A web application for our small local contest KVPA. Users upload their contest logs, the application does log check, evaluate the contest, show results etc.
Simple fast log entry - a tool to enter QSO from your SOTA/GMA/WWFF activations and create the ADIF file - everything just in your browser. It allows you to enter QSO very quickly using a simple syntax. I was heavily inspired by the FLE by Bernd, DF3CB - https://df3cb.com/fle/. His application works only on Windows and Linux using Wine, but I needed something working on macOS and/or Android tablet. I didn't need all the features, just wanted to log QSO from my WFF/SOTA/GMA activation.