Read-only exploratory analysis. Prepared data only; no changes to the original PSK or transmission archives. Geographic grouping and optional bearing/distance filters refer to receiver locations, not determined ionospheric reflection paths.
This exploratory tool asks whether small changes in reported FT8, FT4 and FT2 frequencies over a transmitting session show coherent, recurring variations. It uses your logged transmission frequency and PSKReporter reports from receiving stations around the world.
What the numbers mean: calibrated residual (Hz) = receiver-reported frequency − nominal logged transmitted frequency − that receiver/source/band/mode's fixed calendar-month median offset. The blue dots are observations; optional LOWESS, median and Gaussian curves help reveal trends. Peak/trough timings describe the smoothed curves, not proven physical periods.
A possible explanation is a travelling ionospheric disturbance (TID), but receiver drift, transmitter drift, changing propagation geometry and changing reporting populations remain alternatives. The map filters receiver locations, not directly measured ionospheric reflection points. All analysis is exploratory and does not change the underlying archives.
Prepared 2026-11-05T03:35:49+00:00 · 31546 TX records · 284295 timing-matched reception reports · 2224 sessions · gap limit 10 min
Drag inside the shaded sector to rotate it. Drag its side handles to adjust width, or the inner/outer handles for distance. Numeric controls remain precise.
Simplified azimuthal-equidistant coastline guide centred on IO70pq (20,000 km radius). Receiver locations only; coastlines are indicative and do not reconstruct ionospheric paths.
Comparison medians use unweighted calibrated reports grouped by UTC-aligned 15-second windows, as in Frequency Scatter. They are unsmoothed and do not interpolate across missing windows; geographic/receiver selection applies to both views. This is not an independent correction method.
TX activity timestamps are available after rebuilding the prepared catalogue with v0.00.12.
Choose up to five receivers with repeated observations in the selected geographic path sector. The comparison uses their original calibrated residuals; it does not interpolate across missing reports. Simultaneous TX common-mode testing requires adequate matching receiver reports.
Receivers are ranked by reports, distinct reception minutes and time coverage. Session coverage is the percentage of the session’s 5-minute time bins containing at least one report from that receiver. A bin is counted once per receiver; these are received reports, not independently confirmed TX-cycle counts.
| Receiver | Region | Reports | Distinct minutes | Span (min) | 5-min bins | Session coverage |
|---|
Raw matched residual = reported frequency − logged TX frequency − fixed monthly receiver/source/band/mode median. Baseline requires ≥3 matched reports. Display limits affect only the visible raw points, not LOWESS fitting. All smoothing methods use one receiver-median per 60-second bin, a clock-time window and explicit gap breaks. Peak/trough intervals are exploratory estimates from the primary smoothed curve, not statistical detection of a periodic signal. Results are exploratory, not fitted periodicities. A second smoother is a method comparison, not independent evidence.