Embedded Files
Solar-Terrestrial Data
1. Understanding Propagation (HF Conditions)
1. Understanding Propagation (HF Conditions)
Band-by-Band Guidance: It tells you which bands (e.g., 40m, 20m, 15m) are currently "Good," "Fair," or "Poor." This helps a ham decide whether to try for DX on 20 meters or stay local on 80 meters.
Day vs. Night: Radio waves behave differently depending on whether the sun is up. This chart accounts for that, helping operators plan their "Grey Line" DXing or evening nets.
2. Predicting Long-Distance Success (SFI and SN)
2. Predicting Long-Distance Success (SFI and SN)
Solar Flux Index (SFI): This measures the intensity of solar radiation. A higher number (usually 70 to 300+) means the ionosphere is being "charged" better, which allows higher frequency bands (like 10m and 15m) to open up for long-distance communication.
Sunspot Number (SN): More sunspots generally correlate with better HF propagation. If this number is high, it’s a great time to hunt for rare DX stations.
3. Monitoring Stability (A and K Indices)
3. Monitoring Stability (A and K Indices)
These numbers tell you how "quiet" or "disturbed" the Earth's magnetic field is.
K-Index: This is a short-term (3-hour) measurement. A low K-index (0–2) means the bands are stable and quiet. A high K-index (5+) means a geomagnetic storm is happening, which can cause "blackouts" or high noise levels.
A-Index: This is the 24-hour average. It tells you if the bands have been unsettled lately.
4. Avoiding "Noise" and Blackouts (X-Ray and Solar Flares)
4. Avoiding "Noise" and Blackouts (X-Ray and Solar Flares)
X-Ray: This monitors solar flares. Strong X-ray bursts (Class M or X) can cause immediate radio blackouts on the daylight side of the Earth.
Signal Noise Level: This predicts how much "hiss" or background static an operator might encounter on the bands.
5. Tracking Specialized Modes (VHF and Aurora)
5. Tracking Specialized Modes (VHF and Aurora)
VHF Conditions: For members interested in more than just HF, this section tracks things like Sporadic-E (Es), which allows for unusual long-distance contacts on 6 meters or 2 meters.
Aurora: When the Aurora Lat (Latitude) moves lower, it’s a signal for VHF enthusiasts to point their beams north to try "Auroral Backscatter" communications.
Embeds courtesy of HAMSQL.com
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