Band Conditions

Solar Indices

MUF – Maximun Usable Frequency

Undestanding HF Propagation Numbers

Understanding current HF band conditions is always important when you want to plan your time on amateur radio bands, and this is also crucial when you need to predict HF band openings, in example, during ham radio contests. One of the most important infromation you need to look for is represented by the current solar terrestrial data and current solar activity. Undertanding Propagation Numbers is a key to discover and predict band conditions in the short term period.
Undestanding Propagation Numbers and Solra Indexes
One of the most important Index to focus the attention is the Solar Flux Index also abreviated with SFI. Values between 70-80 are not good, 80-90 are Good, 90-99 are very Good, 100+ are Best. This index represents the total radio noise that is emitted at a frequency of 2800 MHz The solar flux gives an excellent indication of the conditions for long distance contacts, since it is closely related to ionization and therefore to the concentration of electrons in the F2 region of the ionosphere. Conditions to improve, take 2-3 days of high values A and K Index A and K INDEX are measurements of magnetic field activity used in predictions and indicate the daily solar activity. These indexes are calculated on a daily average of samplings, that usually take place every 3 hours. The use of “smoothed” numbers gives more precise results, also because the daily solar activity varies a lot, making it difficult to calculate with accuracy. Lower values means a better solar activity condition.

Current Solar Cycle Sunspot Number

Shows sunspot number. Quantifies the number of sunspots on the surface of the sun.
Source :
Source :
Monthly Sunspot Numbers – Source Australian Space Weather Forecasting Centre

Current Space Weather Report

Current space weather
Shows solar x-ray, proton flux, and geomagnetic activity.

Current 10cm Radio Flux

Source : Shows 10cm radio flux radio emissions. The solar radio flux at 10.7 cm (2800 MHz) is an excellent indicator of solar activity.