After upgrading my ham license to general in March of 2021, I looked to different ways to enjoy the hobby. Antenna theory is very technical and I enjoy learning what I can about it. But at some point, all the numbers, graphs and such are a bit challenging for me. At my home QTH, I have some challenges. I live in an HOA. I live between two broadcast AM radio stations. I live up on a hill 900'. At the top 1200', there is a massive commercial antenna farm. I was able to put up a random wire antenna that was mostly hidden from the street (HOA Rule). That works very well. But one day during the summer of 2021, I looked up at my home and was wondering what I could do to deploy another antenna. All of a sudden it hit me. I recall reading about folks using gutters as antennas in nursing homes, HOA's, etc. So I inspected my gutter on my home. The wheels in my brain were spinning with ideas.
The gutter on my home does not wrap completely around the roof. One side, the gutter is in several sections. The other side, west side, has a more complete length of gutter. One downspout that runs down near my shack. The downspout does not touch the ground. There is a plastic pipe that the downspout rests on at ground level. I examined the west side more and found it wraps from part of the back of my home to part of the front of my home. The downspout is connected to that section.
For my random wire antenna, I use a 9:1 Unun that I purchased off of Ebay https://www.ebay.com/itm/191903715614 . I thought, what the heck. That works well with my random wire. So I figured I would try it on the gutter. I have a spare 9:1 Unun, I took a 6" 16ga wire and removed the plastic sheath from the ends. I put a self tapping screw about 2 inches above the plastic pipe on the downspout. Connected the wire to the screw. The other end of the wire to the Unun. With the random wire, I use a MFJ Common mode choke. https://mfjenterprises.com/products/mfj-915 . I have a 20' and a 30' RG 8X feedline cable with PL259 connectors on each end. I put the common mode choke inline between the two feedlines. I have a ground rod nearby and I connect the PL259 connector closest to the shack, to the ground rod. I find it important to have at least 20' of feedline from the unun to the choke. The shield of the cable acts as a counterpoise. The choke and ground help keep the RFI and other noise out of the shack.
In the shack I use a Morgan Filter M-400X to filter out as much of the AM Broadcast signal flooding my antennas. https://kf7p.com/KF7P/Morgan_Filters.html . I also use a MFJ-939 auto tuner. Icom 7300 radio.
During the summer of 2021 I tested my gutter antenna set up. I was surprised on the first attempt. It worked! 80m to 10m . I didn't need to use my ATU on 20m to 10m. A couple bands in between I needed the ATU. I ran some tests with FT8 and my reach was quite impressive.
After testing the set up, I found a few things that keep me from using it full time. My kid's rooms are up closest to the gutter. The RFI on their headphones and other things was a little annoying to them. The noise being picked up by the gutter is slightly more than my wire antenna. The gutter antenna doesn't 'hear' as well as the wire. Probably because of the noise is slightly higher.
Fast forward to October 23rd 2021. I had a guy come out and trim some trees away from the house. I had to take down the wire antenna. I hooked up the 9:1 Unun to my gutter and used it for several days. I mostly operated digital, as I wasn't feeling well and didn't feel like talking much. I did make some SSB contacts. The gutter antenna performed quite well. Confirmed contacts using FT8 on 40m with South Africa, China and Japan. I used multiple bands. 75m, 40m, 30m, 20m, 15, 12m, 10m. I made contacts on all those bands. All across the country and even into South America. I check into a net on 75m and no one can tell the difference in my signal.
I bet you are wondering what would happen when it rains. It has been raining for three days straight and I cannot see any degrade in performance. No whacky SWR. We'll see what happens when it snows.
Not every gutter is installed the same. If you are looking at this as an option, I would consider how many downspouts. How long of a run from the unun tot he farthest point of the gutter. I would recommend isolating to one downspout. Meaning if there are more than one inline, I would put a rubber or plastic insulator to to remove the other downspouts from the antenna system. If the gutter is too long, I would consider isolating a portion of it to shorten the antenna. Experiment and find what works for you.
It is nice knowing that
I have a viable backup to my main wire antenna. Especially as winter sets in and damage to the wire will probably happen during ice, snow and wind storms.
The contacts made in the three days using the gutter on FT8/4
This is the 9:1 Unun I use for my random wire and gutter.
https://www.ebay.com/itm/191903715614
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