Just a quick follow up on my previous blog about a U shaped dipole I made and put up in my attic.
I decided to make it a “Fan Dipole”. This is a dipole which has one feed point for more than one dipole.
Because I’m mostly using the 20 meter band and the 10 meter band I wanted the dipole to be resonant on these 2 bands. So the two dipoles I wanted in my “Fan” were for 10m and 20m. If I could also have put up a third one for the 40 meter band it would have been nice but my attic is just not big enough!
In the end I put up the second, 10m band part of the antenna, and also put a bit more time into getting the 20m dipole a bit more resonant on 14mHz.
It turned out all my work wasn’t for nothing! I got the 10 meter band dipole quickly 1:1 and after cutting of part (30cm!) of the 20 meter band dipole I got it 1.3:1 !
Almost perfect, in my book, and I certainly will not touch it again because I can only make it worse! If I put a bit more power in the dipoles the SWR of course goes down but never more than 2:1 which I find acceptable!
Of course for the other bands I’m now and then using (40 meter and the 11 meter CB band) I still need to tune but that’s ok.
I’m very happy I got my “U shaped two dipoles in one” working! Did I just invent a new type of antenna? 😉
UPDATE: Just spoke with N3C in Washington, a few hours after the work I did on the antenna. From my location to there is 6167KM and I used a bear foot FT-897 with poor propagation. I guess my new indoor, attic antenna is working! 🙂 Let’s see what it can do when conditions improve!