Recent discussion with a correspondent about the design issue of the so-called Co-Co collinears, vertical collinears made with alternating sections of common coax ranged onto the conflict between the phase velocity of the wave on the inside of the coax and the wave on the outside of the coax, and the difficulty in aligning both … Continue reading Coaxial Collinear – dielectric loading the outer conductor
An exploration of a cophased collinear array with coax phasing stubs explored various structures for encouraging co-phase operation of a 3/4λ vertical over perfectly conducting earth (PCE). This article expands that set with NEC-4.2 models of some variations on the traditional Franklin form of the antenna. Let’s start with review of the traditional Franklin form … Continue reading Co-phased collinear for 2m – discussion of phasing devices
This article has been copied by request from my VK1OD.net web site which is no longer online. The article may contain links to articles on that site and which are no longer available. (Tester 2013) described a coaxial collinear array for VHF/UHF. Tester describes the antenna a collinear is a vertical antenna whose resonant elements … Continue reading Silicon Chip Collinear
At Yet another dodgy coax collinear I wrote about a design published recently in QST. More recently, a ‘design’ has emerged in eHam forums that appears to be identical. Last update: 27th August, 2015, 12:10 PM
Robert Nickels, W9RAN shows a design for an “8 element colinear vertical” for 1090MHz ADSB in QST Jan 2014 in his article Virtual Radar From a TV Dongle. Last update: 6th May, 2018, 6:28 AM
(Franklin 1924) described a technique to cophase sections of a long antenna by “concentrating alternating half wave length portions of the wire within a small space, by winding such portions as inductance coils or by doubling such portions back on themselves so that there is practically no radiation from these portions”. Let’s explore his second … Continue reading Franklin antenna – how does it work?