Thanks for the reply Ron. So far, it's the only one from someone who has actually used the extension kit. I've seen some serious deflection even at 50 feet with a rotor and beam at the top when the w
Well, I've answered my own question: the AB-577 extension kit for 75' can be installed by one or two people, as long as you carefully follow special procedures outlined in the manual. W1ECT came over
This has been a timely thread. As reported previously, I have a 40M 4-square with 240 radials and recently installed a 2-el 40-2CD 40M beam at 50 feet on an AB-577 portable military tower. Testing ov
Dave, You might be experiencing the infamous Sticky Tailtwister problem. This is more common in cold weather, but has been known to happen in warmer weather. Before replacing anything, try rocking t
Thanks to all who helped me get a copy of the 40-2CD manual. If anyone else needs one, W0UN did a Google search and came up with this URL for the manual: ftp://mirage.skypoint.net/pub/members/t/tao/d
David, It depends on how much cable you plan to put through the conduit, how you plan to put it through and how much room you want to leave for future expansion. You can either build the conduit arou
And the winner is... I just had the rare opportunity to compare two very different 40m antennas "side-by-side" and thought the results would be of interest. I've had a 40m 4-square with 60 buried rad
Hi. I'm looking for an EZNEC model for the TH-7. I could also use one for a two-stack. Any help would be appreciated. Has anyone thought about setting up an online library of models for common amateu
I know the AB-577/GRC portable military tower (mast) isn't designed to accommodate a side mounted antenna, and one should never violate the LXC prime directive, but I'm wondering if it can be done an
Bill, I guess it would be reasonably inexpensive insurance to insulate the copper plate from the wood with a layer of high-temp fireproof insulating material, maybe like the rock board they use for p
I'm looking for a copy of the manual for the Cushcraft 40-2CD 40m monoband yagi. Could someone out there scan/e-mail or fax a copy to me? Thanks & 73, Dick WC1M
My experience working with relatively low antennas here (50'-70') versus higher antennas at multis (100'-150') is that height makes a difference not only at the band edges, but also when conditions a
What's the best program out there for terrain analysis? 73, Dick WC1M ________________________________________________________________________ Where do you get ICE bandpass filters & beverage matchin
MARB owners: I use plain-old automotive grease on the inside surface of the upper collar on the rotating base. That's what U.S. Tower told me to use. It's OK to lay it on thick. I use a grease gun to
Jeff, It's amazing -- U.S. Tower provides virtually no installation or maintenance instructions, and you get different answers to questions at different times. I asked the company president about cab
Thanks for the info, Jerry. It reinforces my non-professional opinions about cable maintenance. Also, thanks for the hint on exercising the tower and moving the resting point. It's made me rethink my
I haven't had a problem with that -- there's a very small amount of running, but not enough to lose the grease layer or mess up the tower. I guess automotive grease is designed for moderately high te
Hi. I'd like to compare the theoretical patterns for my C3E, EF-515 (15M monobander) and EF-420 (20M monobander.) Has anyone out there developed EZNEC models for any of these antennas? 73, Dick WC1M