AI4SV/3 QRV

So, I should explain why a crucifix appears to be hovering about thirty feet above my house.

My new HF antenna hovers above the house.

When I got back to the US, I had a hard time figuring out how to put up an antenna at the house that I’m renting in Maryland, just north of Washington, DC. The house is surrounded on three sides by power lines and there’s only one tall tree. After much consideration and with the help of a neighbor’s tree, I finally managed to put a dipole in place just before Christmas.

The two arms of the dipole are 50 feet of Wireman #1 wire. It’s horrible stuff to work with: it has lots of memory and would rather be a coil or if not a coil, an impossibly complicated knot. However, it’s strong, light, and I had it with me. The length was calculated not really based on any sort of resonant frequency, but on the rough distance between the only two trees nearby.

For maximum frequency flexibility and because I couldn’t weight down the unsupported center point, I fed the antenna with 450 ohm ladder line. The plastic cross flying over the property is a plastic connector that connects together the two dipole arms and the ladder line.

I picked up about a hundred feet of ladder line, the centerpiece and a 4:1 balun from RF Connection in Gaithersburg for not much cost at all. The plastic T is in two pieces, which screws together with polypropylene screws and nuts. I probably used about sixty feed of ladder line to bring the signal down towards the house.

A look inside the balun. I took it apart to gunk up the seams with silicon sealant.

Since I can’t pass the ladder line through the house’s metal-framed sliding windows, I attached the balun to a stick driven into the ground and brought the signal to my antenna tuner with about ten feet of 9913F7 coax, so even at higher frequencies, I shouldn’t loose at that much signal due to mismatches.

At the bottom, the feed line is supported by a spider web of guy lines which keep it more or less floating just above the balun. It can move with the wind to some degree, but the bottom end does not flex much.

My LDG-100 antenna tuner is able to match my antenna reasonably on all bands from 160m to 6m. I’ve had contacts from 160m to 17m HF as well as a nice run of contacts last night on 6M SSB when the band popped open towards Florida.

For VHF, I’ve replace my arrow antenna lashed to a ladder with a fence-mounted vertical antenna on load from AF4PD. With that antenna, I’m able to check into my usual Virginia-based nets on 2m FM.

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