This is a very interesting test. When I had the Cushcraft D40 up about 45 feet, on the morning Long Path, it beat the DX Engineering DV-40-P consistently to VK/ZL, ZS and all parts in between. During the night time Short Path, the 40M Phased Array always won. Last night – with the UrbanBeam up only 34-ish feet to ZS6CCY, this was certainly the case. Exactly what I had expected.
This morning, with the UrbanBeam it is about dead equal to the DV-40-P phased vertical array. This means that 10′ does make a big difference on 40M. I worked 3B8XF – Nigel on Mauritius easily with the DV-40-P phased array, and that was after he and I were struggling using the UrbanBeam. I did notice strange conditions where after my QSO – the UrbanBeam came into its own – even as low as it is. Andre – V51B in Namibia is the same story.
Because I have both vertical and horizontal antennas on 40M, this isn’t a problem, and because I have already made all of my DXCC goals, it doubly doesn’t matter – I can rely on the DV-40-P for low angle DX, and the UrbanBeam for higher angle DX. Many times there can be changing conditions and long QSB – so its actually great to have both antennas on 40M.
The bottom line, the UrbanBeam – is the equivalent of the DX Engineering DV-40-P phased vertical array on the morning Long Path, but it is not as good as the phased array on the evening Short Path. I fully expect that with the UrbanBeam up only as high as the ALM-31 plus a rotator and short mast – it will come into its own performance wise starting at 30M and up. I also think if the UrbanBeam were your only antenna on 40M – that you would do much better if you could get it up 50′ or more. So – this is the first limitation of the US Towers ALM-31 that I have seen.
I will repeat this test several more days because we are just getting over a solar storm, and the band is very strange today – so I need more data to see if today is an anomaly or the norm.