Welcome to the third 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.
There's quite a lot in this issue. I'll let the contributors do the talking (or writing) and keep my comments to a minimum.
Kim, N5OP, describes his former condo abode: "I had limited success with a long-as-I-could-make-it vetical dipole that was capacitively loaded on both ends. It worked best on 40, 30, and 20 m but I had RF feedback/grounding troubles on 15 and 10 m. And the RFI problem was difficult to address, since I was doing all of this clandestinely. I camouflaged the antenna with the paint they were using to repaint the condos and it really was hard to see :-) I put it up on a cloudy weekday, about 10 AM, so as to have as few witnesses as possible! I fed it with 450 ohm ladder line through a tuner and worked quite a lot of DX (VE, XE, JA, ZL, VK and a very few Europeans) on whatever power level I could get away with (50 to 100 W). It was fun and I felt that I had pulled it off for the most part, but learned that I couldn't operate as freely as I wished due to RFI and neighbors who objected to the basic idea :-( "
Eric, WD8RIF, was sent overseas for Desert Shield/Storm: "...and the gear I took was a Sangean ATS-803A receiver and a 31 meter dipole, for listening. I strung the wire between our tent and the neighbouring one. It worked pretty well, until the wind destroyed the dipole, at which time I made it into a random wire."
Upon returning: "...I found a nice flat, and the landlord there allowed, nay, helped install a 20-foot mast supporting a 2m quad, a 2m ground plane, and a ten meter dipole. The 2m work was mostly packet, and unfortunately, the 10m was mostly useless due to neighbourhood electrical noise. I also had a 31m dipole strung along the ceiling for the ATS-803A, the same rig that went with me to sand-land."
Mike, KC7IT: "FYI: I once worked a guy in Hawaii via OSCAR-13 who was in a restricted condo situation. He kept his antennas and rotator on a free-standing tripod (like the Radio Shack variety) in his garage, and just walked it out onto his driveway whenever he wanted to operate. So long as you can see the part of the sky you need, altitude is no advantage in satellite work."
Howard, KE7QJ: "I live in a single story townhouse with a flat roof - thus I can erect a 30-m length inverted-V, fed with ladder line, and work 10-40 via an MFJ-948 tuner. Rig is an IC-735 at 100 watts. Works great, but, still, 5-9 into some of one of my neighbor's telephones....We're working on it.
"The townhouse covenants say 'no antennas unless completely concealed from public view.' Well, you CAN see mine, if you know exactly where to look, and from where."
Howard goes on to describe this inverted-V antenna: "...the center point of the inverted V is about 7' above the wood roof. There isn't much metal around, except for the heat pump and its ductwork below the antenna and feedline: far more directly underneath the feedline than the antenna itself. TVI is minimal, although my telephone RFI neighbor reported it to me, along with light interference to her stereo. Her TV is connected to CATV, and I think her stereo is, too. This is my neighbor to the north, and it's a 2-story unit. I would guess that her upstairs wiring, in-line broadside to my antenna, is picking up my signals. My neighbor to the south, literally closer to my antenna, report NO interference of any kind. Then again, they don't have fancy electronics."
As far as grounding is concerned, Howard states: "I am in a one-story unit, thus my station is at ground level. The units are 8 years old, so they're fairly new. The ground wire of the electrical outlets connect to the outside cold water pipe. If I ran a heavy wire to my 'cold water pipe' it means I'm actually forming a ground loop! Thus, I have no real ground. But my dipole has its own built in RF ground, so who cares? If I REALLY want to get serious, I'd get a galvanized ground rod and attempt to drive it into this desert soil. But the nearest soil is 14 feet away! That's going to be resonant on some band or another."
Ed, KM6CG: "My QTH is a third floor apartment. I use a Yaesu FT-301D which is a transistorized 80-10 M transceiver. It's supposed to put out 100 watts when equipped with a 20 amp supply. I run it with the gain backed off and I put out about 20 watts. I run 40 M CW exclusively. I don't really have much luck with SSB at these power levels, but that's OK. I got this on the air to build my code speed and don't operate as much, now that I got over the 13 WPM test.
"My antenna is a 40 M 'Coaxial Dipole' as descibed in 73 in 1981 or thereabouts. It runs around the living room and kitchen ceilings. I use a counterpoise, since I don't have a decent ground. I have a low pass filter, and I don't get into OUR TV or any of the neighbors I checked.
"I live in San Jose, CA. I've contacted about 30 states and two Canadian provinces. 40M is good mostly after dark for me. I can hear a band of stations in the midwest (IL, OH, TN, KY) and another in the west (NV, UT, AZ) as well as lots of Los Angeles and Vancouver/Seattle stations. I hear JAs in the middle of the night, but haven't worked one yet. Haven't tried hard though. I have trouble hearing east coast stations like NY and NE, although I've got a few.
"I also run local two-meter packet. My antenna is a 1/4 wave mobile mount with a 1/4 wave wire dangling, to make a 1/2 wave dipole. It's secured to a strip of aluminum (hanging file folder rail) and it sticks out the window about 18 inches. It's secured by sitting something heavy on the other end."
Be on the lookout for a book by Jim Kearman, KR1S, "Low Profile Amateur Radio, How to get on the air from almost anywhere." This book is at the printer right now and should be available soon for $8.00 from the ARRL and dealers. Jim tells me that it will deal with keeping a low profile (like a spy), setting up a home station, setting up in the field, operating mobile, etc., and will cover HF and VHF/UHF. Some simple antennas are included. It will also address RFI. I'll review it as soon as I can get a copy.
I'm sure many of us would like to hear from anyone with some theories about the RFI (or lack of it) reported by this issue's contributors. Some folks have little or no RFI, and others have to really restrict their operations because of it. Why? The type of rig used? The type of TV, stereo, and telephone? Grounding? (Which may actually *cause* RFI?) Type of transmitting antenna or its placement? Your explanations would be most welcome.
1. Ford, Steve WB8IMY, editor Zack Lau, KH6CP/1, guest author Limited Space Antennas QST December 1992 pg. 85 As Steve says in the introduction to this Q&A column, "ARRL Laboratory Engineer Zack Lau, KH6CP/1, has spent years grappling with the challenge of operating in limited-space environments." A most informative article about losses, RF fields, tuners, and so forth. You can have great SWR but crummy radiation. Read this.
US Snail: Art Winterbauer 428 Francis Street Longmont, CO 80501
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).
(By the way, this newsletter is no longer distributed via packet. Local packet congestion prohibits uploading to either of the local forwarding PBBSs, even in tiny hunks. Besides, you should have heard the HF forwarding stations howl!)