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The mast on the first picture i bought on
the International Amateur Radio Exhibition 2004 in Friedrichshafen.
This is an telescopic mast, when in down position is only 1,89 meter (6,2 ft) and extended 11 meter (36 ft) high is and it's weight is 10 Kg (22 lb). This mast is used by the army and was mounted on land rovers.
On this mast i mounted carbine hooks to have a way to secure the mast with guy ropes. The extra carbine hook on the top is for a pulling rope for the HF wire antenna
The method of erecting the mast is easy;
Thirst erect the mast as it is by guying the bottom part of the mast and guy it such a way that the mast is stands level, otherwise the erected mast will lean over.
Second the VX2000 will be mounted (picture 4) and mount the coax cable with 3 curls in the cable (RF shoke).
Thirst i put a rope through the extra carbine hook, so i can pull up the HF wire antenna later on.
Forth is hook on the guy ropes at the top part of the mast.
Now it's time to extend the mast. Thirst you pull out the top part with the V2000 antenna as far as the rod locks itself. That part is now secure. Now the ring must be tightened, The function of this ring is minimize any margin between the sections and stiffen the mast this way. Do the same with the other sections
After all sections are expended it's time to tighten the top guy's. Now the HF wire antenna can be pulled in top and all systems go !!
This setup i use a lot in the field or when we activate island's as we did on the Ameland expedition 2005
In november 2005 i have made a new mast plate for making setting up the mast more easily. Before i made this mast plate i used a peace of wood on which i screwed a jar top. This solution was functional but had it's drawback's. It was necessary to operate with a second person to hold the mast in it's position. The danger was that when erecting the last part the mast would come out of the jar top and tumble over.
In the new mast plate that is not longer possible. In the designing stage i thought of the possibility to use the mast plate in mobile use (see picture below). This is done by driving the back wheel of the car onto the mast plate.
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the mast plate |
wheel onto plate |
tie-down the mast |
operational |
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The operation to erect the mast is made easy er and could be done by one person.
Put the plate 10 cm (4 inch) before the back wheel and drive the car onto the plate, between the two strips. Then place the mast between the 3 blocks (mast is self supporting in this way). First place the guy rope onto the car top rail and the place the two other guy ropes and check if the mast is standing level.
Place the top guy ropes and the antenna's en erect the mast.