After studying several articles on the webs I tried to figure out a concept construction for my first Cobwebb antenna. An awful lot of tie wraps, a few fishing rods and a almost 50 meters of electrical wire. A few hours DIY in the rain and you see the result beneath. First test results: even at only 2,5 meter height very nice reception! In comparison to my end fed wire it’s a lot less noisy and picks up even very weak signals. Last night I was even listening to local QSO’s of amateurs in North America on 20m! Transmitting is another story on this height of course. No one heard me since, but almost all dipoles are resonant in the band and SWR is good. I think it will be even better when it’s on good operating height of 10 meters. I’m planning to put it on a pole on the roof, then it will be 14 meters high and more ore less 360 degrees free around.
The construction is of course just for testing purposes only. I need to construct another feed point which is waterproof. I’m not satisfied with the tie wrap solution to attach the wires to the spreaders. I think it’s not UV-proof too. I’m thinking about drilling little holes in the spreader to put little screws in them. And the end of the dipole wires I want some elastic pieces in. Then the wires will be tight all the time. Just haven’t figure out what to use for the elastic material yet.
And the baseplate needs some adjustment too, no possibility to attach a vertical pole in it now and the spreaders are not properly aligned. So need to do some rework… Then again, it’s only version 0.1!
Category: Antenna’s
Back in town
Hi all! We’re back in town from two weeks of holiday! It was very nice. We did a lot of hiking, site seeing, enjoying meals etc. Unfortunately I wasn’t able to set up my portable radio kit in Italy at all. The chalets where so tight packet together, it was impossible to throw a wire over something. And if I was able to do that, I would have interfered with at least 10 satellite receivers. So I kept the goodies in the trunk for the first week of the holiday.
In France of course I had more possibilities to setup a nice configuration. I did bring a 1:6 balun with me to experiment with. Two wires of 13,8m and 27,7m where attached to it and hung up between two tree’s. It worked kind of nice but of course only on the lower bands (40 and 80). And there was not much of interesting activity on those bands that week. Then I’ve tried to work my open dipole for 20m and my long wire (16m) that are already installed at the house. But not much luck either. Lots of static (at least I think, or even there are appearing noise generators) and very little signals. All in all I’ve made 4 QSO’s. Not enough to even bring the stuff with me. I consider to buy a dedicated (old) radio for that location to leave. Then I don’t have to bring the heavy stuff with me all the time and I’m able to use a good radio with all filters and stuff even on holidays.
So when someone has good suggestions for a good (second hand) transceiver with (kind of) modern filter methods but isn’t too expensive (I’ll only use it for maybe one week a year), leave me a comment or a message!
Cable thrue the roof
Since I placed my antennas last year, I just put the coax cables thrue the roofwindow. A pretty fast solution but far from ideal, especially in wintertime since I can’t really close one window. Some time ago I bought an rooftile of lead. I think it is originally destined for some kind of mast. But if you mount it up-side-down it could be a great way to put coax cables thrue inside.
So I removed one rooftile and gently drilled a hole in it. Mounted the lead on top of it and put the tile on the roof again. Putted the cables thrue and sailed the whole thing with vulcanization tape. It looks pretty solid, let’s hope that is survives the winter!