G5RV (New Upgraded model)
The G5RV was designed by Louis Varney, who held the amateur radio callsign, G5RV. The design was originally devised in 1946, but it was not until 1958 that it was published when it appeared in the July 1958 RSGB Bulletin.
The G5RV antenna is a classical antenna in our series of HS4 Legendary Multiband Wire Antennas. It covers 7 bands, 10-12-15-17-20-40-80m. Unlike typical antennas, this is a non-resonant, Center-fed antenna. The performance characteristics are quite outstanding. The antenna consists of symmetrical lengths horizontal radiating elements being driven at the center feedpoint through a 600 Ohm open ladder transmission line (TL) of a pre-determined length. The principle of a G5RV antenna utilizes the ladder TL section to help produce the required impedance transformation for taming the SWR to workable limits.
This antenna need an antenna tuner for proper operation however a 12:1 broadband Balun is required to transform the 600 Ohm feeder impedance to 50 Ohm unbalanced for further coax run.. The overall gain on all bands is good with adequate low angle radiation for great DX. This antenna is deployed at a height of 12m (40 ft.) above average quality ground and the design accounts for ground absorption losses, antenna wire insulation dielectric losses, other structural losses, etc.
The antenna produces multiple lobes covering wide azimuth sections on most bands but it also produces several deep nulls along the azimuth. Several bands may have deep nulls in the direction of the default beam heading. Hence, the owner of this antenna will need to find the optimum direction of the radiation lobe on each band to leverage the main lobe which provides maximum gain. This may be on either side of the default beam heading. It may either be achieved by experimentation during the process of familiarizing the antenna characteristics or by referring to the exhaustive set of specifications with graphics and gain map given below... Happy DXing!
Interesting facts: As the antenna was originally designed in 1946 when the number of bands was much less than it is now it was designed to meet the needs of the then bands: 80 metres, 40 metres, 20 metres and 10 metres. At that time 15, 12 or 17 metres were not allocated amateur radio bands so additions such as matching networks have been done to the original construction.