Ham Radio — KO4DDG

Antenna Projects

• 40m Dipole — Build notes, wire lengths, and feedline matching for a resonant dipole.
• Magnetic Loop — Small-footprint loop for MF/HF with tuning capacitor discussion.
• 2m/70cm Yagi — Construction guide for a compact VHF/UHF Yagi for handheld contacts.

Technical Write-ups

• Balun and Impedance Matching — Why baluns matter and simple designs to reduce common-mode current.
• Feedline Loss & Velocity Factor — How to choose coax, calculate losses, and compensate lengths.
• Measuring SWR — Practical methods and understanding what SWR means for your station.
• Antenna Modeling — Intro to using NEC-based modeling tools to predict performance.

General Technical Articles

• Propagation Basics — How HF propagation works and useful resources to monitor conditions.
• Station Grounding & Lightning Safety — Best practices for grounding, bonding, and surge protection.
• Receiver Front-end and Filters — Improving receiver performance with filtering and shielding.
• RF Safety — Exposure limits, measurement, and safe operating practices.

KO4DDG Notes

This collection is curated by KO4DDG — practical project walkthroughs, build photos, parts lists, and wiring diagrams can be added under each topic. To contribute or ask questions, open an issue in the repo or add content to public/ham.html.

Want a quick break? Try the Ham Game where you pilot an Icom IC-52 through a storm of lightning hazards.