PhosphorHertz

PhosphorHz is a real-time HF radio propagation monitor for amateur radio operators. It pulls live space weather data from NOAA's Space Weather Prediction Center and translates it into band-by-band conditions you can act on — right now, from your location.

No guesswork. No stale forecasts. Just the numbers, rendered in a retro CRT phosphor display that would look at home in a Cold War listening post.

BAND CONDITIONS
See at a glance which HF bands are open, marginal, closed, or blacked out. Conditions are calculated from real-time solar flux, geomagnetic activity, and X-ray flux data — not generic regional forecasts. Each band shows your local status plus path-specific conditions to every DX target you configure.

MUF CALCULATION
The Maximum Usable Frequency for a 3000km reference path from your QTH, derived from Solar Flux Index, solar zenith angle, and depressed by geomagnetic activity. Individual MUFs are calculated for each great-circle path to your DX targets, because the ionosphere doesn't care about averages.

SOLAR INDICES
All the numbers that matter, updated in real time:

Solar Flux Index (SFI) with 30-day trend chart
Planetary Kp Index with 24-hour bar chart
Estimated Sunspot Number (SSN)
GOES X-ray flux class and latest flare detection
Solar wind IMF Bz component
NOAA R/S/G scales (Radio Blackout, Solar Radiation, Geomagnetic Storm)
Running A-index and solar wind Bt
Each index includes a plain-language assessment: is the F2 layer well ionised? Is the geomagnetic field quiet or disturbed? Is the solar wind coupling or shielded?

3D GREYLINE GLOBE
A SceneKit globe shows the solar terminator — the boundary between day and night — in real time. The greyline (twilight zone along the terminator) is where lower-band DX propagation is enhanced, and it's rendered as an amber band you can see at a glance.

The globe displays coastlines, your QTH position, DX target locations, and great-circle paths coloured by band condition. Drag to rotate. Double-tap to recentre on your station. Hit play to watch the Earth spin.

SPACE WEATHER ALERTS
NOAA SWPC alerts and warnings filtered for HF relevance. Flare events, geomagnetic storms, radio blackouts — the alerts that actually affect your ability to make contacts, with full detail on tap.

DX TARGETS
Configure up to five target regions. PhosphorHz calculates path-specific propagation for each one, using gr