- Replace stale April 2026 manual weights with recalibrated values
- Document native hybrid-sigma data in data flow section
- Note refractivity factor now uses native 10-50m resolution
- Add hourly grid integration section to Part 12
- Expose duct_info (count, freq, thickness) in scoring factors for UI
Backtest on 11,431 native profiles (2026-04-11):
- Drop duct_usable_10/24/47ghz (always 1.0, no discrimination)
- Drop bulk_richardson (near-identical QSO vs baseline means)
- Document all feature results with signal strength assessment
- theta_e_jump is strongest native discriminator (44% lift)
- best_duct_freq and duct_thickness show clear physical signal
Add sections for all three new data sources in Meteorological
Foundations: path-integrated scoring strategy, ERA5 reanalysis
for pre-2014 contacts, RTMA 15-minute surface analysis. Update
calibration dataset summary with ERA5/RAOB/RTMA coverage.
Solar time (longitude/15) replaces fixed CDT/CST offset for time-of-day
scoring. Correlation analysis shows dramatic improvement at higher
frequencies: 24 GHz rho jumps from 0.056 (UTC) to 0.188 (solar), and
75 GHz corrects from spurious -0.39 to physically correct +0.24.
Comprehensive description of atmospheric science behind the predictions
for meteorologist review: refractivity-propagation connection, four
ducting mechanisms, HRRR model usage, frequency-dependent effects,
diurnal/seasonal cycles, and known limitations.
Previous thresholds (-500 to -60) were calibrated for radiosonde data.
HRRR profiles have coarser vertical resolution, with gradients clustering
between -40 and -130 N/km (median -70). Nearly all grid points were
falling through to the default score of 42, wasting the refractivity
factor. New thresholds (-200 to -40) spread across HRRR percentiles.
- Replace piecewise knife-edge loss with P.526-16 Eq. 31 single formula
- Fix diffraction parameter ν to use standard formula instead of ad-hoc approximation
- Implement Deygout 3-edge method for multiple obstacle diffraction
- Add dynamic k-factor from HRRR refractivity gradient (falls back to 4/3)
- Terrain worker now looks up nearest HRRR profile for atmospheric correction
- Update algo.md with P.526-16 methods and k-factor table
- Fix pre-existing map_live_test antenna height default (33 ft, not 8)
- Expand ITU-R section with recommendation numbers, titles, and usage
- Document all 8 external data sources with API URLs, volumes, fields
- Add derived parameter documentation (sounding params, HRRR profiles)
- Document live scoring pipeline (grid resolution, update cadence, retention)
- Add contest bias and rain model caveats to known issues
- Document Finding 11: regional QSO performance by Maidenhead field
- Explain why regional weight adjustments are not justified
- Fix algo.md table formatting (blank lines before tables for Earmark)
- Change page title from Phoenix Framework to North Texas Microwave Society
Poll UBNT AirFiber radios (AF11X + AF60-LR) every 5 minutes via
net-snmp CLI, storing signal metrics in commercial_samples. Fetches
ASOS weather alongside each cycle for propagation correlation.
Includes 7 seeded link definitions, Oban cron worker, and net-snmp
in the Docker image.