Figure 1: The cloud warmer for eighty meters. Click to enlarge.
So, on eighty meters my signals were always in the dust. In the fall season, with thunderstorms hundreds of miles away, I had an S6 static noise level, with crashes above that. It was enough to drive me back to the forty meter CW band. The problem was twofold. First, I had a very “loaded” 80 meter attic dipole, and secondly, it was a dipole. Hence it was poor to begin with (being both loaded and in the attic), and a great static noise scooper (like all dipoles are).
The solution? A (mostly) horizontal loop. Why horizontal? Because it’s tough to find the vertical space in any attic for 285 feet of wire!
Now, even horizontally, I was going to come up short. 50×2 + 35×2 = 170 feet, which is well short of the requirement. So, about 70 feet of the loop is an up-and-down pattern, affixed to those six inch plastic stand-off insulators, supported from the gables. The other eighty five feet? It’s in the nooks and crannies, believe it or not. It adds up. I used Gimp on FreeBSD in etch-a-sketch mode to draw the antenna, and it’s definitely not drawn to scale (for those observant types who did the math).
So, how does a mostly (seventy five percent) horizontal, twenty five percent vertical “horizontal” loop perform? Let me tell you.
First, I decided to run “almost QRP” mode on the antenna. Lord knows what the voltage and current distribution is on this monster, so I ain’t taking any chances. Experimenting with ten watts of “near QRP” power, put thru a coaxial Q matching section, resulted in the highest dB numbers I’ve ever recorded on reverse-beacon.net. Many of the stations were receiving me at 35+ dB, and a couple over 40 dB! I’d never seen such a thing, even on the forty meter CW band, where I have a full size (albeit very bent) dipole.
The noise? It dropped from S6 to between zero and S1! Suddenly, I had an eighty meter DX machine. I’d never worked *any* DX on eighty meters. The six’th contact I made with the loop was EA1DR, in Spain. I was converted at that point. Loops are in, dipoles in the bin.
Now, in the lore, a horizontal loop is a cloud warmer. What the provocateurs of the lore mean to say, is that the radiation is all blasted straight up, like a HAARP competitor on steroids. But, I’ve read competing theories on this, saying that some fine medium angle radiation results from the horizontal loop configuration. And – my loop does have some vertical component, although I doubt it means anything. It seems I have real nice lobes up into New England ( 700-1000 miles). The european skip I’m hearing may be partially due to a convenient QTH on the east coast, and a good bounce on the salt water. But, this thing not only warms, it cooks, and not just the clouds.