Yesterday I posted about tree antennas. Some of the references used a Rowland ring to couple RF into the tree. What happens if you use something a bit more conductive than a tree? Would it still work as an antenna?
I was intrigued so I tried it. I used a goal post on an oval near me. The video below shows my results. The post would only have been about 6 or 7 metres high. So not even a full quarter wavelength on 7 MHz. I don't think you'd call it a good antenna but I still made contacts.
There are opportunities for other experiments. Eg what if you used both goal posts and two Rowland rings. Then fed it with coaxial cable. Would they act as phased verticals on receive and be directive? Or what about something bigger Eg the very tall light poles around the oval. Maybe coaxial cable (use the outer braid) wrapped around a flexible sponge cylinder would work? If you've tried this or similar ideas let us know your experiences in the comments below.
PS: For more portable antennas, including ones that perform better than above, check out Hand Carried QRP Antennas. Favourably reviewed. Thousands sold. Available as low-cost ebook or paperback.
Hello Peter, do you use insulated wire for the coil? I'm not shure after reading and searching for rowland ring on the internet. It seems to work and there are not many that heard about this unusual way of loading. 73, Bas
ReplyDeleteBas - insulated - eg enamel or plastic covered - would be better as you won't get shorted turns or inadvertent contact with the pole.
Delete