Frustration and Encouragement
As of the last posting, I had strung a slinky dipole in my townhouse attic. However, I had a hard time getting out and hearing anyone, got some nice RF-tingle in the shack, and eventually quit trying, and things just kind of lingered around. With no antenna analyzer it was hard to tune the slinkies to be resonant; the manual tuner got it to match on the radio side, but how close to resonant the actual antenna was remained a mystery. Eventually the radio gear went from collecting dust to sitting on a shelf.Then the usual suspect, KE3DYX, got a new HF rig and dragged me to a nearby park. We cobbled together a speaker-wire dipole (just soldering the wire to a UHF connector), and pretty much instantly were talking to the Caribbean.
This was awesome, and there were a few things I immediately took away from this. First, I didn't realize what a half-way decent antenna was supposed to sound like on the radio, as far as noise floor, signal levels, all that. Realizing that it's not about trying to discern scratchy voices from deafening hiss was an epiphany. Second, it showed me that with less than $10 in supplies and some wire hanging from a garden trellis you can in fact use my FT-450 to do DX. Third, it got me excited about amateur radio again.
Emboldened, I got an automatic antenna tuner to replace the manual one I had, having seen the night-and-day difference one makes in convenience. I also started to play around with antennas in the attic/indoors/outdoors, reading articles and books, and trying various things. And nothing seemed to work worth a darn in the house.
My townhouse is an interior unit, i.e. it's flanked by two other connected units on both sides. It's deeper than it is wide, and the ridge of the roof runs side-to-side. It's not wide enough for even a 20m dipole, and the attic is barely 7' at its highest point. A good 90% of the neat attic antenna plans I could find wouldn't fit. Still, I did some zigzag dipoles, random length dipoles etc. but nothing would work. Even the same speaker wire dipole that had worked fine draped over trellises was next to useless and refusing to tune in the attic. There is no feasible way to have an antenna outdoors.
After talking to the helpful folks at Reddit and a number of other places, I figured out that the problem was the construction of my townhouse. Most of the framing is metal instead of traditional 2x4s, and this couples with most any antenna; even having them at 7' is still way too close, especially since many of the metal beams run parallel to the antenna.
The Solution
After a bit more thought I realized that I could turn this to my advantage. So, I went ahead and bonded some of the top plates together and got garden fencing which I laid down in the attic, making the attic floor into a pretty decent ground plane. Onto that I stuck two JetStream mobile loaded whips -- as you can see below, the height still prevented me from having them perfectly vertical.
I experimented with different grades of garden fencing; you can see the coarser one on the right, but most of the image on the left is also covered by a much finer mesh (anything will work electrically, it's mostly how easy it is to cut and work with). Garden fencing is preferable over poultry fencing, as garden fencing has welded joints and poultry fencing is just wrapped wire. As an aside, I wish I could have still bought proper Hamsticks, but AES was already sold out. So far, three out of the four JetStreams I've ever bought have been defective in some fashion or another.
The result of this experimentation was general success. The bonding and garden fencing took the noise floor on 20 and 40 meters from around S4 to between 0 and 1. So far, so good. Also, with some patience I managed to tune the antennas; for a given subsection of the band they're very nearly 1:1 SWR. I could now hear signals from the noise, but had still a hard time making contacts. RFI concerns also kept me from running particularly high levels of power.
The Final Piece
As per KE4DYX's suggestion, I gave digital modes a try.First was PSK31. However, the lack of error correction, and the general chaos on the bands combined with my non-optimal setup made operating it a bit annoying. Also, I kept seeing this strange other digital mode on my waterfall / spectrogram display. A bit of poking around revealed this to be JT-65A, a weak-signal mode originally intended for meteor scatter, Earth-Moon-Earth VHF and other exotic uses, but increasingly used for HF DX.
This has been my ticket to operating from a townhouse. JT-65 is very strictly structured, and in some ways resembles contest QSOs more than anything, since there's almost no free-form communication. It lets me, however, reach Europe, the southernmost tip of South America and South Africa from my attic with a $25 antenna that's barely 7'. Other error corrected weak signal modes, such as Olivia, are also on the horizon, although I haven't been lucky in finding much of them on the air yet.
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