I’m antenna swapping once more here at K5ND. You may have seen my article on EZNEC Modeling as I investigated options for upgrading from my 8-Element Quad for 2 meters.
K5ND Antenna Merry-Go-Round
Changing antennas is my usual mode of operation, as you well know from reading this blog. The focus is on improving performance within my yard and pocketbook constraints.
With six-meter antennas, I’ve pretty much reached the limit of my yard and the ability of a fiberglass pushup mast to keep everything in the air. With two meters, I’m trying to improve my contest results, take advantage of tropospheric or sporadic E openings, and engage in meteor scatter contacts.
Reviewing Two-Meter Antenna Options
The quad did well in all those activities, but I wanted to find some more gain. My first thought was to add a second quad with a side-by-side mounting. But first, I needed to verify the current gain and understand the actual benefits.
What I found with the EZNEC modeling was that the quad came in at 11.37 dBi gain. Adding a second quad would increase the gain by roughly 2 to 2.5 dB. So, 14 dBi in a stretch for a heavier antenna and some severe leverage on the end of the fiberglass mast.
Looking at the Yagi alternatives, complete with some of my own EZNEC modeling, shows that 9-element versions offer 14+ dBi gain at a considerable saving in weight. I also looked at 10-, 11-, and 12-element Yagis. But the boom length and weight made those a stretch too far.
Winning Antenna Selection
The winner was the M2 2M9X 9-element Yagi. Its boom length is 14.5’ with a fantastic weight of 5 lbs. This is half the weight of the other options and even 2 lbs lighter than the quad. The downside is that it is costly compared to the alternatives. But it does fit my requirements perfectly.
Building the M2 2M9X Yagi
One reason for the extra expense of this antenna is that it includes two sets of elements. One set is for the SSB portion of the band, and the other is for the FM portion. It’s also true that M2 charges more for their antennas.
I had previous experience with their antennas. That includes the M2 Satpack EB144/EB432 eggbeaters and the M2 6M-3SS. I found both to be built exceptionally well, and they worked well. I’ve sold the eggbeaters but still use the 6M-3SS at home and when roving.
The M2 2M9X went together very well. The directions were sound; everything was there and fit together perfectly. You must pay attention to element lengths as they vary and do not uniformly get shorter toward the front of the boom. The documentation has a warning, but it’s easy to miss.
Testing the M2 2M9X Yagi
I used the quick-release boom to mast mount. So it fits on the pushup mast nicely. Plus, at 5 lbs, it’s easy to lift into place.
I set the T-match to the recommended length, and the SWR came out precisely on the mark. See the nearby reading from the RigExpert AA-600.
I also tuned in a nearby beacon, comparing the quad and the stacked Omniangles in the attic. It showed the appropriate difference in gain over both. I tried it in the 144 MHz Fall Sprint, but the activity here in North Texas is minimal, and there were no openings.
The next big test, barring a tropo opening, will be the Orionids meteor shower in October. I look forward to adding a few new two-meter grids to the log during that one.
Great story about your upgrade to the 9 el M2 2M yagi. I use the M2 2m7 yagi on 2 Meters. The boom is short enough I can put it inside my car for portable use. The antenna is well built, sturdy, and effective for meteor scatter, Es and tropo.
Hi Jon, I really like the build quality of the M2 antennas as well. Currently have the 9-element 2-meter Yagi and 3-element 6-meter Yagi on the push-up mast. They are very lightweight. I managed to work FK8HA and a couple of Australians using the 3-element Yagi rather than the bigger, heavier 5-element Directive Systems Yagi I used during E season. Very happy with these antennas. 73, Jim, K5ND
Jim I did the same thing about 5 years ago. Retired my Cubex 8 element quad for the M2 9E and I will say this antenna outperforms the quad. I read some articles that the quad loses efficiency on 2M after 4 elements. I will say the F/B is slightly better on the quad and its quieter. The gain on M2 is better. You can see my yagis on my QRZ picture, also have the M2 10E for 222 and a K1FO 15 for 432. I had them too close on the array, so I spaced them better my picture for this has not been updated.
David N2SLO
Hi David, Thanks for your comments and further insight into the quad and M2 9-element Yagi. I like them both, but the 9-element Yagi clearly has more gain. It helped me work W7OUU on 2-meter meteor scatter recently at 1156 miles. We couldn’t make it happen with the quad trying for the past year. But thanks to the Yagi and the Orionids, we finally completed the QSO. The Quad design probably needs some adjustment in the element spacing to improve the gain. But that’s way beyond my skill set. 73, Jim, K5ND