KBěZEV/Rover

My vehicle setup in the 432 Sprint contest,
April, 1998


Photo 1
Here you see my 1992 GMC Safari Van, with a pair of yagi antennas mounted on top of it. This is a view from the left rear quarter of the vehicle. In the background, you may notice my rooftop tower, currently holding only a 6 meter beam. Once the rotator has been repaired and re-installed, both of these antennas and several more will be mounted on that mast.

Photo 2
The upper antenna with vertical elements is a Cushcraft A270-10S, a dual-band (2 meter/70 cm) antenna, with 5 elements on each band. This was connected to a Yaesu FT-5100 dual-band FM rig. Below it, is a Cushcraft 719B "Boomer" antenna for 70 cm, with 19 elements on a 13.5 foot (6-wavelength) boom. It was connected to a Yaesu FT-847 rig for SSB contacts, and did virtually all the work in this contest for me.

Photo 3
A close-in view of the mast. The bottom half is a 30" tall steel pipe, 1.25" ID (about 1.5" OD), which is threaded into a flange on the roof of the van and has another pair of back-to-back flanges on its top end. Four white nylon guy ropes attach to these flanges. Another 30" tall steel pipe is threaded into the top of the flanges, and both antennas are mounted on that section, above the guy ropes.

Photo 4
A view from above the van, looking towards its rear. Note the pair of 2x4's that run across the width of the van and are bolted to the factory-installed roof rack. The white guy ropes to the rear of the roof rack are connected to the middle of the mast, as was shown in photo 3. The two yellow ropes also visible in the photo are attached to the rear bumper in an inverted-V formation, and are only intended to prevent rotation of the antenna assembly.

Photo 5
A close-up view of the attachment of the 2x4's to the roof rack. Each 2x4 has two holes drilled near each end, spaced to match a U-bolt assembly. The U-bolt grabs the roof rack, passes through the 2x4, passes through a steel plate, and is tightened down with a pair of wing nuts. This makes the entire assembly easy to remove after the contest is over.

Photo 6
A close-up view of the wooden platform that sits atop the pair of 2x4's, and holds the galvanized steel flange that the mast pipe screws into. If you look VERY closely, you might be able to see the sheet of steel that is placed between the board and the 2x4's to provide extra strength. Also, the astute observer will notice that the platform board is made out of "chip board", which is not the optimal type of wood for this sort of installation. It was lying in my garage, and the weather was dry, so I got away with it. For future rover-mode contesting, this board would be replaced by a solid piece of wood and would be painted to provide some protection from the elements. I also plan to investigate the cost of a solid 24"x24" sheet of nice, thick aluminum sheet.

Photo 7
A very close-up shot of the junction of the two mast pipes. Note that the white guy ropes have steel protectors to prevent them from being cut or worn at their passage point through the eyelets on the bottom of the flange pair. These eyelets were leftovers from the purchase of an in-tower thrust bearing. They were provided in case my application had been to put a thrust bearing above the top of the tower, running to guy ropes. Since the thrust bearing will be going in the top of my rooftop tower, the eyelets will not be used in that installation. Also note that I used a small piece of "chipboard" between the two back-to-back pipe flanges, and it is not the ideal material for this spot either. A solid piece of painted wood would (will?) be a better choice for the future. Still better would be a small sheet of thick aluminum.

Photo 8
This photo shows the van and its antennas from the driver's side, as it sits parked in my driveway near the garage where the rooftop tower that eventually got to hold all these antennas (and more).