Welcome to the seventh exciting, thrill-packed issue of Condo Communicator, a newsletter devoted to those amateurs who, for various reasons, must configure their stations to operate from restrictive areas such as condos, apartments, townhouses, neighborhoods with outdoor antenna restrictions, ships/boats, mobile homes, or wherever they fry their burgers and call QTH.
It's been a while since issue #6. I've been pretty busy with work, not to mention getting a new QRP transmitter working (mostly) and just plain operating on the air. And, uh, my dog ate the issue I was writing. Y-e-a-h, *that's* what happened.
You would think that the challenge in operating from restricted space would be in the HF part of the spectrum. After all, the antennas are large and you have to run a lot of power to be heard, right? Evidently, not so.
From what we've seen in the first six issues of the newsletter, putting up an HF antenna in restricted space may involve some athletic ability, such as crawling around attics, but once there the antennas seem to radiate well enough. Even when running low power (under 50 watts) to minimize RF coupling into power lines or overpowering appliances, covert operators have been making themselves heard. Of course, these stories might have turned out differently if we hadn't been enjoying the benefits of the great solar cycle 22 as it peaked during 1990 through 1992.
As Lew McCoy, W1ICP, is fond of saying, just get as much wire as possible as high and clear as possible to radiate a signal. But as we cruise deeper into a stagnant Sargasso Sea of solar inactivity, we may find that our modest crafts no longer will do the job for us (talk about stretching for a metaphor...whew).
This is when covert ops either move someplace where they can erect larger antennas or they do as the radio pioneers did and relay their messages. Back then, they sent their messages in 30 to 100 mile hops by spark gap or CW. Nowadays, the covert operator can put up a tiny two-meter antenna and use an HT and a computer to connect to local, but well-equipped, packet gateways between the VHF and HF worlds. Some communities are lucky enough to have satellite gateways, like N0NBH in Denver, CO, where hams can use low-end packet stations to communicate with satellite bulletin board stations.
I think the most technical challenge facing the apartment or condo dweller isn't HF or even VHF communications: it's UHF. That 30- meter loop strung around the bedroom ceiling will radiate through plaster and wood. But wet shingles will seriously attenuate 70 cm or shorter wavelengths if you're shooting for a satellite. Besides, unwieldy, high-gain UHF antennas are much more difficult to install and operate in cramped quarters than a length of wire tacked up on walls. A typical OSCAR array looks like an anti- aircraft battery as it is rotated and tilted to track its targets: who has an attic big enough for that?
So, we condo dwellers could rely on two meters for our connections to better equipped stations, which can then in turn allow us to connect to other stations. Or, perhaps we will use the microwave spectrum, connecting to better equipped stations with small dishes that can be mounted temporarily on the outside of our buildings or on portable masts we can quickly set up in other locations.
Hopefully, people who do operate the UHF spectrum from portable or restricted quarters will contribute notes this coming year to the newsletter, as well as folks who have discovered various gateways in their communities. During the coming years, as the ionosphere becomes a poorer reflector of signals, it will be interesting to see what ingenious strategies covert operators come up with.
Only one station desription this issue.
Until recently, I lived in a townhouse and couldn't put up a "real" antenna. I started with a random wire, strung from my basement operating position, up the basement stairs and around the corner and diagonally across my living room ceiling. I tuned it with an MFJ 949 tuner, and did okay with it for a while.
Later I ran coax from the basement through a couple of closets (where the holes in the floors/celings would be hidden) and connected it to a 40-meter dipole wrapped around the ceiling perimeter of a second-floor bedroom. This worked quite well for me for a long time. I seldom ran more than 50 watts from my Drake TR3, and usually it was more like 10-35 watts. Never had any problems with RFI, though I mostly operated very late at night.
Cleary, Jack, WN2Q. "Another Attic Antenna," The QRP Quarterly, July 1993, pp. 21-22
Jack describes an attic-mounted delta loop for low-angle radiation, one of the eight loops described by Doug DeMaw in his W1FB's Antenna Notebook. Jack's loop is calculated for 14.060 Mhz with the loop formula: Length = 1005/F (Mhz). Jack had a real adventure installing the antenna in the attic of his small, one-story bungalow, including a surprise descent into a closet, much to the consternation of his XYL. Fun to read and great info.
Belrose, Jack, VE2CV. "An Update on Compact Transmitting Loops," QST, November 1993, pp. 37-40.
A great article that sums up the theoretical underpinnings of small transmitting loops and which also compares the performance of different types of loops. Some of the commercially available loops mentioned are the AMA series (a German brand: Abstimmbare Magnetische Antennen), the AEA Isoloop, and the MFJ Super High-Q. Loops, while not comparing favorably with dipoles on 75 and 40 meters, do compare well with mobile whips, for example. Generally, the larger the diameter of the loop and the diameter of the loop conductor, as well as the greater its height above ground, the better the low-angle radiation pattern given a horizontal orientation. How about from the balcony of a 20-story building? The article doesn't say.
Okay folks, let's hear from you! Send your notes, ideas, station description, war stories, and so on to me at my packet address or:
US Snail: Art Winterbauer
10047 E. Mexico Ave.
Denver, CO 80231
Also, listen for snippets of this newsletter on Hap Holly's (KC9RP) Radio Amateur Information Network (RAIN), heard on various nets or by direct dialup (708-299-INFO, no charge except for long- distance costs).
73,72. Art.
N0OQS @ W0GVT.#NECO.CO.USA