Compromise and Improvise: Not always a bad idea
HF and Apartment Dwellers don't go together. It's like vinegar and milk. Sure, there are plenty of apartments or townhomes out there that can support (within reason) an outdoor HF wire antenna, or there are certainly commercially made compromise antennas out there. But I'm sure you can guess the efficiency will be in the toilet, and you're going to likely have to keep the power to a minimum.
I have personally tried several indoor style antennas with varying
degrees of success. First up was a Super Antenna (think Wolf River Coil style)
in the middle of my living room floor near the sliding door to the balcony. At
this point, my apartment was on the second floor. Several 10ish foot ground
radials were spread out around it. I was running 10 watts of FT8 through it and
checking PSKReporter to see where I was being heard. Although I was making it
out consistently in the region, I was fighting to make a contact with a station
only about 400 miles away. He was hearing me around a -20, and I was getting
him around a -3. 5 minutes of back and forth later, I got the contact.
However, that's not something that can be left around on a semi-permanent
or reliable set up. I tried moving the coil to my outside balcony, and didn't
have much more luck there. Plus, if you breathe on the antenna the wrong way,
you go from a 1.5:1 to about a 4:1. Safe to say I sold the antenna and searched
for another.
A friend of mine suggested stringing christmas lights across the ceiling,
and running a ground radial from the back of the transceiver across my living
room floor. I did have some better luck with that antenna, managing a contact
from Ohio to Texas on 5 watt FT8. But again, this was not something I could
keep up full time. Plus, my G90 was struggling to keep the SWR under a 2:1. And
for those who know, they know the G90 could tune a wet spaghetti noodle on 20
meters with a decent chance of success.
At this point I was getting fed up. Surely there had to be something out
there that would be a semi-permanent, small space, and easy to use antenna
system. But those three descriptors usually mean a pretty high price tag. I
picked up a Chameleon Antenna Mag Loop for around $500, with the 80 meter loop
extension. Several weeks of research online and YouTube videos led me to
believe this was a perfectly capable unit that would guarantee me at least
regional contacts. Unfortunately though, this antenna I found to be incredibly
overexaggerated, as I don't believe I managed a single contact on it, whether
indoors, outdoors, it didn't matter.
Point of the story is I have had a hell of a time finding an antenna that
would work indoors or on a balcony, and could also prove to have some decent
success on HF. I gave up on at home HF for a while, and kept my go-box ready
for Parks on the Air activations instead.
Late last night I was at home with a friend of mine, also a ham, who I
told I really wanted to play radio. Now, I have a ground floor apartment, and
the other antennas I own have been sold or traded over time. I currently have a
20 meter mini MFJ hamstick, maybe some 22 gauge wire, and a way too long piece
of coax. I've never had much success with the hamstick, so it spends most of
its life in a closet. But we had an idea: Instead of building an antenna, why
not use something antenna shaped?
My apartment building is two stories high, and has gutters that run up
the side of the building entrance, several feet away from the main walls. I
knew the gutter was isolated from the ground, as there was a plastic 90 degree
bend to connect it to the long downspout running across the lawn. It did not
connnect to the long horizontal piece running across the top of the building,
and we figured if we could tune it, let's see how well it performed. We hooked
the gutter to my MFJ-941D manual tuner with strands of wire we pulled from a
rough looking CAT5 ethernet cable, and twisted the end of each strand together
so it could reach. We ran a 10 foot piece of the frankencable over to the
bottom of the gutter and connected it to the screw at the bottom holding the
plastic 90 degree bend piece in place, and then ran a 20 or so foot piece of
the frankencable along the ground perpendicular(ish) to the gutter out of the
tuner.
This was late at night, and although there wasn't anything necessaraily
wrong or illegal about what we were doing, we wanted to keep stealthy to avoid
any suspicion from cars passing by in the parking lot, or neighbors that may
have been sitting outside. We knew we would have to keep the power as low as
possible to avoid any hazards of RF affecting people or their property, so we
knew this would be a QRP operation, so I set my FT891 for 5 watts.
Unsurprisingly, I was able to tune for a near perfect 1:1 SWR match. I
say unsurprisingly, because this MFJ tuner has been able to find a match for
just about anything I've thrown on the end of the random wire and ground lugs.
Immediately my WSJT-X started to flood in with US West Coast calls, with
average RSSI of about -15. I was a bit surprised by this, as I figured we were
well past grayline, but 20 meters had a good opening last night. So I called
out as QRP on FT8. (I know this is kind of a cheap shot practice, but I wanted
to make at least one contact with a rain gutter)
First successful contact was with Arizona on 5 watts. Next was several
Northern California, some near Portland, one in Vancouver, and a very
surprising DX contact with Spain. All on 5 watts. This is performance I haven't
even seen a decent dipole or Inverted V manage. This "antenna" acted
as an almost inverted inverted L. So a basic L? I don't know. But I was beyond
impressed by how well it did.
The point of this post is to show that sometimes in this hobby, it's
important to think outside of the box. With just a box of crap I had sitting
around, I was able to make very decent distance FT8 contacts, without needing
to drop several hundred dollars on a commercially made compromise antenna that
likely won't work, or without having to work within the confines of the typical
apartment dweller limitations. Would I suggest doing this permanently? No. This
is a recipe for your landlord getting pissed off at you for messing with the
buildings infrastructure, or constantly sending RF into your neighbors living
space. But just to prove that it is possible? Totally worth it.
This antenna build was entered into an RF exposure calculator before
transmitting with assumed worst case scenario calculations, and was determined
to be at a safe distance from others under an uncontrolled enviornment (approximately
1 foot of distance).
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