A 4-char locator covers ~70 km × 100 km, which dwarfs HRRR's 3 km
native cell and any midpoint we'd derive for the calibration corpus.
Storing those samples gives the recalibrator geometry that's
indistinguishable from noise.
fetch_grid/2 now returns {:error, {:short_grid, key, grid}} for any
locator under 6 chars after Maidenhead validation. The spot is
dropped before it reaches the aggregator, so neither pskr_spots_hourly
nor pskr_calibration_samples ever see it.
Spots that include subsquare (EM12kl), extended-square (EM12kl37),
or extended-extended-subsquare (EM12kl37ab) precision now keep
that resolution end-to-end. Previously we truncated everything to
4 chars at parse time, which collapsed distinct paths into the same
row whenever two spotters shared a field.
The aggregation key uses the full grid as reported, so two
spotters in different subsquares of `EM12` produce two rows —
correct, since they are physically different paths. Any spot that
fails Maidenhead validation (odd length, illegal char at position
N) is still dropped via the same error path.
Storage normalizes to uppercase so the unique index doesn't split
on case. Maidenhead.valid?/1 already accepts both cases on input.
Subscribes to mqtt.pskreporter.info:1883 over plain TCP and folds
every reception report into hourly aggregates per
(band, sender_grid_4, receiver_grid_4). Each spot is the empirical
"propagation actually occurred on this path right now" signal we'll
correlate against HRRR atmospheric state to recalibrate the scoring
weights. Aggregating at the path-hour bucket collapses 50-reporter
QSOs to one row instead of 50.
Topic filter anchors on USA (DXCC 291) on either sender or receiver
side so the broker pre-filters out everything outside our HRRR
domain. Bands subscribed: VHF and up (6m, 2m, 70cm, 23cm, +
microwave) — HF is dominated by ionospheric propagation, which this
project doesn't model.
Pskr.Client cluster-elects a singleton via :global.register_name —
all replicas start the GenServer but only one connects to MQTT;
the rest stay in :standby and watch for the leader's nodedown to
re-run election. Off in dev/test, on by default in prod
(PSKR_MQTT_ENABLED=false as kill-switch).
Pskr.Aggregator buffers in memory keyed by Pskr.path_key/1 and
flushes every 60s via Repo.insert_all/3 with an additive
ON CONFLICT (count summed, SNR envelope by GREATEST/LEAST,
modes unioned via unnest+DISTINCT). Idempotent across overlapping
flushes and across leader handover.
Dockerfile sets BUILD_WITHOUT_QUIC=1 — emqtt's transitive quicer
dep wants CMake + OpenSSL headers we'd otherwise have to add to
the builder image just to never use QUIC over plain MQTT. Base
image is unchanged; the new dep compiles cleanly into the existing
prop-base runtime.
