Installing the SteppIR 3el Antenna
Since I was last on the air in 1998 a lot had apparently happened in ham radio technology and what was this 12m and 17m and 30m thing?. Bob Allphin, K4UEE told me about the FluidMotion SteppIR antenna and, when I visited their website and read about the technology it just blew me away. I HAD to have that antenna!
Stepper motors (like in a PC hard disk) had been adapted to dynamically and precisely create Yagi antenna elements for your desired frequency at the push of a button! Push a button and you have a perfectly configured, 3-element, no-compromise, monoband antenna for any frequency between 6m and 20m! This is so cool that, even if it didn't work as well as another antenna, I simply had to have that technology. I joined the SteppIR Yahoo Group and started reading posts. I learned that not only was the technology super cool, the darned thing worked - and worked better than any other multiband antenna. No traps, coils or other tricks - just an infinite number of monoband yagis.
The way it works
Stepper motors, one for each element, are mounted to the boom and each drives a spool of flat, copper-beryllium tape. The tape moves inside fiberglass "elements" (hollow poles 36' in length overall). A 12-conductor (or 16-conductor for the 4el Steppir) control cable runs to a small control box in the shack. The controller has factory-preset buttons for each band (selectable by band segment) and you can set your own element lengths manually if you wish.
When you push a button, the controller signals the stepper motors to roll out (inside the hollow fiberglass "element" tubes) the precise amount of tape to create driven, director and reflector elements for the chosen frequency. If you move to a higher frequency band, the controller instructs the stepper motors to reel in the proper amount of tape for that frequency. That's all there is to it!
Oh, and one more nice feature. With a button push (and in 2.5 seconds) the controller switches the length of the director and reflector to (effectively) "turn" the antenna 180 degrees. Awesome!
And, finally, another button push and the antenna configures itself for bi-directional operation by changing the reflector to another director. This would be excellent for a net control station...
In "General Coverage" mode, you can connect the antenna controller to your rig and the antenna will automatically follow the radio dial as you move from band to band and up and down in frequency. Amazing!
Ordering -- and waiting
On February 2, 2004 I ordered my 3el SteppIR antenna. They have dipole, 2el, 3el and 4el antennas. I chose the 3el because I just don't have enough room for the 4el boom to get it installed. The 3el boom is 16 feet long and the 4el boom is 32 feet long.
I have enough turning radius once I get above the trees but I could never get it installed w/o a crane -- and that wasn't in the budget (nor would my neighbor appreciate the encroachment on his property!)
I called FluidMotion and ordered the antenna, 150' of 12-conductor control cable, the rig control feature and the ICOM interface cable. They told me that they were running 4-6 weeks behind. This wasn't a problem for me as it's still wintertime and, while Atlanta doesn't get that cold, it does have its days where it's unpleasant to work outdoors.
The same day I ordered the antenna, Bob and I visited Ham Radio Outlet to buy a new rotor. I had done a little research and decided on the Yaesu 800DXA rotor. It had the necessary specs to handle the 6.1 sqft wind load of the antenna AND it had the computer control functionality that I wanted.
Next, I ordered coax, rotor cable and PL-259s from The Wireman. I figured I'd go ahead and get the rotor mounted and cable run before the antenna arrives.
My idea is to have a computer logging program hand off a spot frequency to my ICOM 765 and have it in turn "tell" the rotor which way to point and "tell" the SteppIR controller to set the proper antenna configuration. Heck, that would be so neat I probably wouldn't even work anyone, just sit back and watch the automation!
Again, I took Bob's advice and ordered DX4Win for my logging/rig control program. I also joined the DX4Win Discussion Group to learn more about the program.
We travel a lot so I called FluidMotion the week before I expected delivery to ask that they let me know before they ship so I could have someone here to receive it. They said that they'd had a quality problem with an inbound shipment of the fiberglass poles and there would be a bit more delay. No problem.
In the meantime I looked up a bunch of hams I used to be tight with in the 70s and 80s and found that good friend Dave Johnson, K4SSU, was still doing tower work. Excellent! I'm no longer in the proper shape to climb and, while the tower does retract to about 26' it still requires some climbing. Dave generously offered to handle that for me when the time came.
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