WB4DBO gives his review of the New EF-QUAD
I received your EF- Quad this date and within one hour I had it hung and trimmed! Instructions are very simple and installation is easy! NOTE: An antenna analyzer is not a requirement but without one the job would be much more time consuming!
First of all, the environment in which this antenna was installed and trimmed was generally open space over a lawn with no obstructions within 30 feet of the antenna. The coax end was attached to a wooden patio pergula at a height of nine feet. The closest structure was my brick home at approximately 18 feet from the coax end.
The far end was tied off to Dacron cord terminating at approximately 25 to 30 feet. The wire was over open lawn with no trees or structures within 30 feet.
The antenna analyzer used to trim/tune the antenna was the “Rig Expert, Model AA-30.”
The following outlines my experience tuning this antenna for use with the CW portion of each amateur band specified for this model. Those who operate both SSB and CW will probably need to tune differently, although, even tuning for the lower part of each band still kept the SWR below 2.1 : 1 across the entire band!
Setting my antenna analyzer for a frequency of 7.050 the antenna exhibited a SWR of 1.2 : 1 basically flat across the entire 40 meter band. At the high end of the band the analyzer indicated a SWR of 1.45 : 1. The antenna impedance indicated on the analyzer was 62 ohms. This closely tracks the chart included in your antenna characteristic graph in the provided tuning instruction manual. As such, I made no tuning changes to the length of the antenna on the 40 meter band.
Setting my antenna analyzer for a frequency of 14.050. Using the analyzer, it indicated the lowest SWR of 1.2 : 1 was located at a resonant frequency of 13.700 Khz. Making two trips to tune the 20 meter stub I trimmed a total of two inches off the 20 meter tuning stub resulting in a 1.2 : 1 SWR. Again, the analyzer graph closely matched your graph for a SWR across the 20 meter band of an SWR no higher than 1.4 at the high end of the band. The antenna impedance indicated on the analyzer was 60 ohms. The fact the lowest SWR was well below the amateur band supports the suggestion one should consider using an antenna analyzer to ascertain the true SWR and thus allowing a more accurate tuning scenario.
Setting the antenna analyzer for a frequency of 21.050 the antenna analyzer indicated a SWR of 1.2 : 1 across the entire 15 meter band. The indicated impedence was 51 ohms. No trimming was required on this band! The SWR graph across the band was again within the specifications included in the antenna tuning instructions.
Setting the antenna analyzer for a frequency of 28.040 the analyzer indicated a SWR of 1.5 : 1 across two thirds of the lower portion of the band at my designated operating frequency of 28.040. Toward the far end of 10 meters the SWR exceeded 2.0 : 1. A person wanting to operate both CW and SSB could easily trim the tuning stub to achieve a SWR within limits for both modes. Indicated impedance was 35 ohms.
Following are observations not specified or advertised with the product.
The EF-QUAD will tune in the 17 meter band with an Elecraft K-3 internal tuner. The tuner bypass SWR was around 3 or 4 : 1 at 18.080 Mhz. The tuner easily brought the SWR down to 1 : 1.
Also, the K-3 tuner easily brought a 10.115 Mhz SWR down to 1 : 1 – The bypass SWR was about 6 : 1.
Congratulations on a produce that does what it says it will do! Easy to hang and easy to tune (with an antenna analyzer!)
Willis Haycock – WB4DBO
VKJRC is portable with Par EndFedZ Antennas!
Click on Image Above to View his Newsletter (3.17MB PDF)
Jack VK4JRC, reported that on June 13, 2012, his club had a special event callsign VK100WIQ celebrating 100 years of the WIAQ in Queensland.
“Our main antennas were the EF-20, EF-40 that I have owned for about 3 years and the new EF-80 which I got recently. The performance of all antennas was great, with over 120 logged contacts over the weekend including night operations, the EF-80 performed very well, with contacts as far away as New Zealend (ZL). Power supplied by genset and batteries to the Icom 7000 and Icom 718, we even had an Icom 1209 23cm radio as well. 17 members attended, with some camping overnight in the rudimentary facilities.”