↑ Understanding HF Propagation Banners

This page is part of the project "Understanding HF Propagation"
by Doron Tal, 4X4XM

Banners provide online information on radio propagation conditions for specific ham bands, including current status and numerical values, based on real-time data from various sources.

Please see the following banner courtesy of Paul L Herrman, N0NBH as an example:

Explanations for the numerical indices displayed on this banner:

SFI - Solar Flux, 2800MHz (10.7cm)ref. (SFU units) correlates with F2-layer ionization; higher value better HF conditions.
SN - Daily Sunspot Number is a measure of the solar activity; like SFI it correlates with enhanced F2-layer i.e. better HF conditions
K-Index: Geomagnetic Disturbance; good conditions K < 3   |   A -Index: 24 hours Average; good conditions A < 10
X-Ray; Scales: A, B, C, M, and  X (range from A0.0 to X9.9) affect D-region absorption
304 Å: Total Solar Radiation SEM (Solar EUV Monitor) wavelenth: 304 Ångstroms (30.4nm) that affects F-layer ionization
Ptn Flx - Proton Flux Density in the Solar Wind
Elc Flx - Electron Flux Density in the Solar Wind
Aurora indicates the strength of the ionization of the E-region in the polar regions
MUF Boulder - Maximum Usable Frequency (MHz) at Boulder, CO, USA, updated every 15 minutes.

HF conditions are global average predictions over 24 hours. The regional conditions may differ significantly.
GeoMag Field - Calculated - Earth`s Geomagnetic based on K-Index. Updated every 3 hours.
Sig Noise Lvl - Calculated every ½ hour: S-units (Solar Wind and Geomagnetic Activity)

Read more about Solar-Terrestrial Data relevant to Global Propagation Conditions


The project "Understanding HF Propagation" provides a detailed overview and tutorials on HF propagation.

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