By John Beattie, California. USA
|Recently I had written about the Alpha Delta DX-SWL sloper antenna that I had put up in place of an Eavesdropper trapped dipole. I'd like to share what I originally posted about the comparison between the two, and make some more up to date observations.
The sloper is a multi-band trapped antenna that covers medium wave through 10 meters. The antenna is about 65 feet long, and Alpha Delta recommends placing the peak at 25 - 30 feet with the lower end at 8-9 feet. In my installation, the feedpoint of the antenna is mast mounted at around 30 feet, with the lower end at around 8 feet.
The antenna is fed to the receiver with 75 ohm quad shielded coax. I also utilize a 50 foot random wire, which I feed through a balun to coax into the shack. I hook both antennas up to a modified MFJ 1026 phasing/noise cancelling unit (modified so that I can change what is considered the main and auxiliary antenna at the flick of a switch).
The Sloper performs noticeably better than the Eavesdropper in the 90 and 60 meter bands. The Sloper especially gave the 90 meter band a boost, and this during the spring and summer, with some tentative Indonesian and PNG stations in the early mornings.
I put the antenna up in April, so I can't wait to see what the winter will bring with the new antenna. I'm also excited about the prospect of finally logging some 120 meter band stations during the winter (the antenna is supposed to work well on this band as well), as the Eavesdropper was essentially dead on 120 meters. The sloper is a marginal improvement on 49, 41, 31, 25 and 22 meters, although the signal to noise ratio on the sloper seems to be better.
The 19, 16, 15, and 13 meter bands are a toss up between the two antennas (with both antennas doing a very good job on those bands).
So the sloper has made my tropical band DXing much better so far, even in the middle of summer. Hopefully winter will bring a few surprises in the form of some 120 mb loggings (such as the Australians on 2310 and 2325!).
The antenna can be ordered directly from Alpha Delta http://www.alphadeltacom.com or from Universal Radio www.rffun.com in Ohio. the price is around 80 USD. I've enjoyed the results from this antenna so far!
John Beattie, California, USA