With very few exceptions, every contact I’ve ever made has been with a dipole as the antenna. I use the term dipole loosley to include trap dipoles, fan dipoles, monoband coax-fed dipoles, the G5RV and my current antenna, a ladder-line fed dipole (which I’ll abbreviate here as LLFD).
I’ve used these antennas for the dual reasons of economy & simplicity and what follows is an explanation of why I’ve settled on the LLFD as opposed to the others.
First, here’s what I want in an antenna: cheap, easy to hang and good performance. I am primarily a DXer, so I define good performance as the ability to continually be adding new countries to the log on all HF bands – all with a single antenna.
Early on, I ruled out the “fan” dipole (too complex to erect for what it offers) and various flavors of trapped dipoles (too heavy and lossy for what it offers). Monoband dipoles are fine but…they’re monobands – I want a single antenna that I can use on all HF bands.
That leaves the G5RV and the LLFD.
In 1990, I bought a pre-packaged G5RV at a ham radio store in Newington, Connecticut. It was convenient, I didn’t have to cut, measure or solder. And it had a proven history as a performer, used by thousands – it wasn’t a gimmick antenna like the old Gothams.
When Louis Varney developed the antenna that would bear his callsign as its name, the HF bands consisted of 10, 15, 20, 40 and 80 meters. No WARC bands were even on the horizon at the time. Today, the G5RV is incorrectly touted as an all-band antenna for HF when nothing could be further from the truth (and it has been “iffy” on 10m from the beginning).
Yeah, it’ll tune 10, 17 and 30 meters. So will a 100w light bulb and a Cantenna.
Rather than re-write what’s been written, have a look at this analysis by W8JI. Halfway down is a chart showing feedline VSWR for a G5RV. A bit further down is another chart showing losses in dB incurred with those VSWR values. Pay particular attention to performance on 30 meters.
At this particular time in Connecticut, my one-of-a-kind Heath HW-9 (built beneath the Pacific Ocean onboard a nuke submarine) was loaned out to a fellow ham and my only remaining rig (try not to laugh) was a 30m one-watt Ramsey transmitter and a Magnavox D2999 receiver with BFO. And the G5RV, strung between oaks at my hilltop house in the appropriately named, Oakdale, CT.
So I was stuck on 30 meters with an antenna whose worst performance was on 30 meters.
At some point during these Navy shore duty years, a nor’easter took down the G5RV. The HW-9 loanee recommended an 80m dipole and his donation of enough 450-ohm feedline to mate antenna to Ramsey/Magnavox. I did, and the difference in performance was almost tangible.
No, I never had both antennas up simultaneously for A/B tests. And perhaps a better station would have disguised the difference between the two antennas. And a comparison on 20 meters would not have revealed much, if any, difference between them.
On the bands for which it’s designed, the G5RV delivers. My logbook from HW-9 contacts on bands other than 30m proves that, to my satisfaction. But it is not an all-band antenna, despite what the ads say and it was never intended to be.
More measured and graphed data on the G5RV is presented at this website, which concludes in part,
from a matching perspective, the G5RV is far from being an all-band antenna. With a modern in-built auto-tuner, it’s at best a 3-band antenna (80m, 20m, 12m). With a good external tuner it’s probably a 5-band antenna (80m, 40m, 20m, 15m, 12m). Other bands can be brought within matching range by incurring losses in the coax.
Of course by using a good external tuner and avoiding the coax section by bringing the ladderline all the way to the shack, losses will likely be acceptable on all bands 80m thru 10m ……… but is the antenna then a G5RV or simply a 102ft multiband doublet?
So the LLFD was selected based on sequential elimination of its competitors. Its main advantage is low feedline losses despite high SWR. Take a look at this page (halfway down) comparing losses of ladder line compared to various types of coaxial cable.
My LDG autotuner allows my 80m LLFD to present no higher than a 1.8:1 SWR to the rig. This is on 40 meters – other bands are 1.2:1 or less.
My current DXCC count with an 80m ladder-line fed dipole is 302.