A daily indicator of geomagnetic activity.
Level | Index range |
---|---|
Quiet | 0–7 |
Unsettled | 8–15 |
Active | 16–29 |
Minor storm | 30–49 |
Major storm | 50–99 |
Severe storm | 100–400 |
You can find a detailed description of how the A index is calculated and how its values are related to radio signal propagation conditions in the Solar Guide , published by Radio Netherlands’ Media Network.
A means for indicating a shortwave broadcast target area, devised by the International Telecommunication Union, Radio division. The world area is divided into a total of 85 zones. Please see the CIRAF Zones reference list in this online help, and visit the ITU‑R broadcast reference data page, which provides some CIRAF Zone maps .
A graphic representation of schedule information. On a Gantt chart, activities are listed down the left side of the chart, dates are displayed across the top, and activity durations are displayed as time‐placed horizontal bars. Also referred to as the bar chart.
A 3‑hourly indicator of geomagnetic activity.
Level | Index value | Corresponding A index value |
---|---|---|
Quiet | 0 | 0 |
Quiet | 1 | 3 |
Quiet | 2 | 7 |
Unsettled | 3 | 15 |
Active | 4 | 27 |
Minor storm | 5 | 48 |
Major storm | 6 | 80 |
Severe storm | 7 | 140 |
Severe storm | 8 | 240 |
Severe storm | 9 | 400 |
You can find a detailed description of how the K index is calculated and how its values are related to radio signal propagation conditions in the Solar Guide , published by Radio Netherlands’ Media Network.
A classic algorithm for computing MUF values on mini‐computers. The original MiniMUF formulae were presented in the QST magazine: Rose, Robert B., “MINIMUF: A simplified MUF‑Prediction Program for Microcomputers”, QST December 1982, pages 36–38.
Maximum Usable Frequency—the maximum frequency on which high frequency radio signal propagation is possible. MUF depends on the time of year, on the time of day at the transmitter and receiver locations, and on the current solar conditions.
An indicator of the intensity of solar radio emission.
You can find a detailed description of how the solar flux is measured and how its values are related to radio signal propagation conditions in the Solar Guide , published by Radio Netherlands’ Media Network.