I was looking for coax to replace the Quarter wave transformer in a commercial VHF Folded Dipole Antenna. Calculations for coax required to match 300 ohms to 50 ohms revealed that a coax with an impedance of approx 120 ohms is required. Z= √300 x 50 equals 122 ohms. RG63 has an impedance of 125 […]
Posts in category Ham Radio
Have you ever wondered why most of our Amateur Radio equipment is designed for 50 Ohm transmission lines? The following graph was originally produced by two researchers, Lloyd Espenscheid and Herman Affel, working for Bell Labs in 1929. The graph shows the power handling and voltage handling ability of various coax impedances.
A sea rescue Amateur Radio Emergency Communications In July 2012 Mike Hall VK8MH took part in the Sail Timor Leste boat rally on board his highly modified Triton 24 Colleen, along with his crew, brothers Gary and Geoff and his daughter Kylie. Mike arranged for Scheds on 40 Meters at 07:30 and 16:00 daily for […]