Single Path Prediction¶

Predict the signal-to-noise ratio for any HF path from the command line.

Usage¶

ionis-validate predict \
    --tx-grid <grid> --rx-grid <grid> \
    --band <band> \
    --sfi <value> --kp <value> \
    --hour <utc_hour> --month <month>

Parameters¶

Parameter	Required	Description	Example
`--tx-grid`	Yes	Transmitter grid (4-char Maidenhead)	`FN20`
`--rx-grid`	Yes	Receiver grid (4-char Maidenhead)	`IO91`
`--band`	Yes	Band (160m, 80m, 60m, 40m, 30m, 20m, 17m, 15m, 12m, 10m)	`20m`
`--sfi`	No	Solar Flux Index (default: 150)	`140`
`--kp`	No	Kp geomagnetic index 0-9 (default: 2)	`3`
`--hour`	No	UTC hour 0-23 (default: 12)	`14`
`--month`	No	Month 1-12 (default: 6)	`1`

Example¶

ionis-validate predict \
    --tx-grid DN26 --rx-grid IO91 \
    --band 20m --sfi 150 --kp 2 \
    --hour 14 --month 6

Output:

IONIS V20 Single Path Prediction
=================================
  TX: DN26 (47.0N, 112.0W)  →  RX: IO91 (51.5N, 1.0W)
  Band: 20m  |  SFI: 150  |  Kp: 2  |  Hour: 14 UTC  |  Month: June
  Distance: 7,842 km  |  Azimuth: 39.2°

  Predicted SNR: +0.432 sigma  (-6.8 dB)

  Mode Verdicts:
    WSPR (-28 dB):  OPEN
    FT8  (-21 dB):  OPEN
    CW   (-15 dB):  OPEN
    RTTY  (-5 dB):  OPEN
    SSB   (+3 dB):  CLOSED

How It Works¶

The predictor:

Converts Maidenhead grids to latitude/longitude
Computes path geometry (distance, azimuth, midpoint)
Engineers 13 features matching training exactly
Runs the V20 checkpoint (single forward pass)
Denormalizes the sigma output to dB using per-band WSPR norm constants
Applies mode thresholds to produce open/closed verdicts

Mode Thresholds¶

Mode	Threshold	What It Means
WSPR	-28 dB	Beacon minimum — signal floor
FT8/FT4	-21 dB	Digital decode limit
CW	-15 dB	Readable by experienced operator
RTTY	-5 dB	Machine-copy reliable
SSB	+3 dB	Voice-quality communication

A prediction of -6.8 dB means WSPR, FT8, and CW will work. RTTY is marginal. SSB needs a stronger path.

Tips¶

Try different hours: HF propagation changes dramatically by time of day. Sweep --hour 0 through --hour 23 to find your opening.
Check SFI sensitivity: Compare --sfi 70 (solar minimum) vs --sfi 200 (solar maximum) to see how much the sun matters for your path.
Storm impact: Compare --kp 1 (quiet) vs --kp 5 (moderate storm) — high-latitude paths are most affected.
Band comparison: The same path may be open on 20m but closed on 10m depending on solar conditions.