A while ago I did build my first 30m WSPR-RX to participate in the WSPR-challenge. I must admit it is very addictive! It did not took long before I was building my second WSPR-RX. This time a little bigger since the first one was too much miniature. Also I wanted to add some tweaks. Continue reading →
Last contest it became clear I need just another change on the antenna part of my setup. Since last year my neighbor has completely revamped his attic and situated his study room there. That is bad news for me because now he’s only 2 meters underneath my antenna wire. His PC monitor really dislike HF and starts striping with even the slightest signals (even 5 watts). Of course we can replace his monitor with a more HF-proof type. But an antenna wire this close will always produce some RFI.
So the idea is to move the antenna away from his attic. Fortunately our house has two chimneys, one on each side. The house is 6 meters wide (some 19 feet) so using the other chimney, the antenna wire will be further away. Hopefully my other neighbor doesn’t have anything HF-sensitive on her attic!
I’ve had quite a few antenna setups in the past years. Started with a mono-band wire dipole for 20m. Then a multi-band dipole for 40m, 20m and 10m. It was a little too much wire in the air. Then tried a combination of a Cobwebb antenna (10 – 20m) and a horizontal loop for 40, 80 and 160m. The Cobwebb worked great but I got a little tired of answering the question about the “cloth hanger” on my roof. The horizontal loop worked great for Europe, but it was almost impossible to work DX on it. So those went away. Then I put up a Fritzel FD-4. Great antenna but it was a little too long for my garden. I had to wrap the wire around my garden what wasn’t too nice to look at (according to “she who must be obeyed”). I went for the shorter version of the FD-4: the Fritzel FD-3. The original commercial one to be exact. Also works great! Missing 80m capabilities where more serious then I hoped for. Also: my guess was the Off Center Fed (OCF)-design of the antenna maybe produced some of the RFI-problems at my neighbor.
I changed the Fritzel FD-3 for a homemade ZS6BKW as suggested by Wilko PA3BWK and inspired on Fred PA3YH‘s antenna project. That works kind of OK (couldn’t test it properly on 20m and up yet) but it didn’t resolved any of the RFI-problems with the neighbor which I had hoped for.
I kind of like the ZS6BKW-inspired design of 2x 13,75 meter wire fed with 10 meters of open wire feed line. The mismatch can be fixed with an antenna coupler like a Icom AH-4, Kenwood AT-300/KAT-1 or a SGC-product.
Hopefully the weather allows me to move the antenna this weekend so I’ll be ready for the next contest.
Last night I leave WSPR on for the whole night to see what happen. According to propagation rules, the best opportunities on 80m should be around the greyline. In the evening that means in western Europe I should get signals out of the east and in the morning I should get signals out of the west. A little disappointed I was this morning when the only thing I saw is stations from Europe. Could it be my antenna? Bad propagation on 80m? Not enough WSPR-station on the air? I guess my S9 noise level on 80m don’t help much.