Topband: RX epiphany?

[Bob Kupps]

Hi well I've only been QRV since June here but the QRN level seems noticeably worse than my previous QTH in the W6 desert even though my current QTH is also quiet, limited by only propagated QRN. Many times I cannot copy stations answering my CQ on 80 so it either means they are running less than my 99W (unlikely) or else they have a lower RX noise floor than I do, either due to lower ambient levels or a more directive RX antenna (although one of the local big guns claims that observations on the high bands going back 20 years show HS consistently getting out better than we can hear, and has even mapped out a region where this one-way propagation seems to occur. I happen to think that electromagnetic waves should behave the same way in antennas, the ionosphere and the ground regardless of whether they are being transmitted or received but we all have our pet theories...) I just read a USN study that monitored noise levels throughout the year at 20, 35
 and 65 degrees latitude and at times the noise was up to 12 dB stronger at 20 (my latitude) than 35, where most of our QSOs are with. 

Anyway to the point of this post I have decided to take down my half-completed 160m 4 square and use the available land to put up a RX 8-circle array. I can shunt feed a 21m top-loaded tower for Xmit that could be located about 5/8 wave from the nearest RX element and around which I could put a somewhat better ground system than I could around each 4sq Xmit element as well. It seems to me I could easily make up the 3-5 dB loss on Xmit with an amp if desired. Since the 80m yagi up 3/4 wave has a strong high angle secondary lobe I think our 80m RX would improve as well.

I have a couple months to think about it before it dries enough to do any work so would appreciate any comments on this rather radical change in plan, especially by you guys at tropical latitudes.

73 Bob