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DXRadar Blog

Science-backed guides on HF propagation, solar weather, and operating — written for licensed amateur radio operators who demand accuracy.

Recent Articles

pota-fieldintermediate

Best Portable HF Radio for POTA & SOTA in 2026: QRP Rigs Ranked by Need

The best portable QRP radios for POTA and SOTA in 2026 — from a $123 pocket rig to a 100W field workhorse, ranked by how you operate. Real prices, honest picks.

pota-fieldbeginner

Best LiFePO4 Battery for Ham Radio & POTA in 2026: Field Power Ranked

The best LiFePO4 batteries for ham radio and POTA in 2026 — sized for QRP, 100W field days, and everything between. Real capacities, prices, and runtime math.

pota-fieldintermediate

Solar Power for POTA: Panels, Controllers & Power Stations That Keep Up

How to power a POTA station from the sun — panel wattage, MPPT vs PWM controllers, and power stations sized to your radio's real current draw. Honest picks, no hype.

beginnerbeginner

Best HF Antenna for Beginners in 2026: Your First Antenna, by Situation

The best first HF antennas in 2026 — dipoles, no-radial verticals, and portable options ranked by your space and budget. Honest picks that get you on the air.

pota-fieldintermediate

Best Portable HF Antenna for POTA & SOTA in 2026: Verticals & Wires Ranked

The best portable HF antennas for POTA and SOTA in 2026 — verticals, wires, and modular systems ranked by how you deploy. Real prices, honest picks, fast setups.

beginnerbeginner

Best HF Radio for Beginners in 2026: 4 Rigs That Match Real Band Conditions

The best beginner HF radios in 2026, matched to the propagation you'll actually work — from a $450 SDR to a do-everything base rig. Honest picks, no hype.

propagationintermediate

End-Fed vs Dipole vs Vertical: Which HF Antenna Should You Build?

End-fed half-wave vs dipole vs vertical — the three HF antennas compared for 2026. Which is best for DX, small yards, POTA, and beginners, and why. A clear decision guide.

solar-weatherbeginner

Solar Flare Classification: A, B, C, M, X — What Each Class Means for Radio

Solar flares are ranked A through X on a logarithmic scale based on GOES X-ray flux. Learn what each class means for HF blackouts, D-layer absorption, and radio operations.

beginnerbeginner

Why Are the HF Bands Dead Today? Diagnosing Dead Bands with Solar Data

HF bands dead today? Five causes with a diagnostic flowchart: low SFI, high Kp, solar flare blackout, polar cap absorption, and wrong time of day. With live data.

pota-fieldintermediate

Winter Field Day Propagation Guide: Cold Weather Operating and Band Predictions

Winter Field Day is the last weekend of January. Different propagation, colder conditions, and unique band strategy versus summer Field Day. Complete guide for 2026.

vhfintermediate

Sporadic-E Propagation: The Complete Guide for 6m Operators

Sporadic-E (Es) opens 6m and VHF without warning. Learn the physics, seasonal patterns, MUF thresholds, and how to catch openings in real time.

propagationbeginner

Solar Flux Index (SFI) Explained: What It Means for HF Propagation

The Solar Flux Index (SFI) measures the Sun's radio output at 2800 MHz and predicts ionospheric conditions. Learn band-opening thresholds with live SFI data.