At the risk of sounding glib or like a F12 fanatic (which I am, but not for any financial or commercial reason), this is a no-brainer to me: C-51XR @ 120' Some 80 meter antenna @ 101' - probably a Ma
Would take a heckuva tower -- I'm not sure even Rohn 45 would be heavy enough, but otherwise I agree. The only issue I can see is that running the C51s and C31s together for a 4-high stack could be p
The offsets can be compensated for easily with a little longer coaxial calbe that acts as a delay line to electrically aliegn the driven elements, when pointed in the same direction. Its already been
On 3 bands with the same length of coax? 73, Pete N4ZR Don't forget to update your entry in the contest station database http://206.102.70.3/search.htm -- FAQ on WWW: http://www.contesting.com/towert
How do you do that with one feedline when more than one band (not a direct harmonic) is involved? 73 Barry -- Barry Kutner, W2UP Internet: w2up@mindspring.com Newtown, PA FRC alternate: barry@w2up.we
Sure, you are compensating for a distance in the open with a piece of coax with that has the same velocity factor on the bands in question. It does assume that you are not using 1/4 wave matching sec
The velocity factor in the coax is the same on all bands (of course), but the amount of phase shift between the two antennas will be different on different bands if unequal line lengths are used. The
Hmmm.... I hadn't thought about it that way. So the 5-foot driven element offset (for example), is twice the phase shift (in degrees) on 10 that it is on 20, and the same length of coax (5 x VF) prov
Pete, I think you're (and they) are right. I was thinking the difference in phase velocity between coax and air made the compensation unequal on the different bands, but I think I now see the (speed
If the phase length of the free space horizontal offset (FSHO) is xdeg on 20 then it is 21/14 * xdeg (or 3/2 * xdeg ) on 15, and 28/14 * x (or 2 * xdeg) on 28. If the coax is .66 VF, then the length
Great idea but F12 says that 37 foot spacing is really the minimum; they'd prefer more for these longboom antennas. Cheers, Steve K7LXC Champion Radio Products Tower Tech -- FAQ on WWW: http://www.co
The ultimate antenna collection requires the ultimate tower. Look in the catalogue for the tower that carries 102.6 SqFt. -- 73, Kurt, K7NV -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html
I can remember staring at pictures of the TELREX BIG BERTHA for days! Wasn't those supposed to be the ultimate. I know some are still around. 73 Greg K9ZM -- FAQ on WWW: http://www.contesting.com/to
See below: That's what I've heard they say. HOWEVER, if you model a pair of C31XR's in EZNEC, to allow element interaction, rather than the abbreviated method used in TA... then... ONLY the 20 meter
To continue on this business of C31XR stacking, I would like to thank Natan Huffman for forwarding some literature, wherein lies the genesis of the 37-40 foot spacing. I have determined much smaller
Without messily interspersing a lot of comments throughout Guy's interesting post, I'd just observe that Force 12's stacking data also address gain at 20-10M and F/B at all three frequencies, and the
Guy, interesting analysis on stacking. I was just wondering if your max gain numbers were at a constant elevation vs. stack height or not. I wouldn't think so. In other words, wouldn't the optimum st
used Good thought. Natan, W6XR, has some of the data that he may be willing to share. The 30 foot spacing (I think) is what WX0B came up with too. He gave a VERY interesting talk on spacing at Dayton
Hi Greg, The Big Berthas may be the ultimate by somebody's definition. Maybe someone around here knows what the Bertha's are rated for, I'm pretty sure it not this much. I think one would start shopp
In my view, the ULTIMATE ONE TOWER SYSTEM is an oxymoron. -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com Administrative requests: towertalk-REQUEST@c