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Telescopic mast installation and Spiderbeam antenna tests



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Photo441

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Photo 441
On this picture, the Telescopic aluminium mast is almost completely deployed, it is 12m high above the roof with only one guy line set. This is to have an idea about its height when the Spiderbeam is mounted on the top.

Photo 443
Now, the mast is firmly secured by 3 guy lines set. In the second plan, Spiderbeam antenna is finally not so imposing when space is available. Maybe it will be possible for me to add more fiberglass segments for working on 30m band later on.

Photo443

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Photo442

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Photo 442
The same telescopic mast with its 3 guy lines set in place. We can see the 40m inverted Vee dipole which will definitely stay there after Spiderbeam installation.

Photo 444
Spiderbeam is now on the telescopic mast at about 2,50m high, above the carport roof, and i began tests at once.

Photo444

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Photo 445
small modification:
The 2 telescopic tubes on the top had been replaced by one galvanized TV tube which will better resists when tightening the spider centre joint U-bolts, and also to resist in torsion when wind strongly blows.

Photo445

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Photo446

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Photo 446
Only the 8 telescopic elements of the mast, only 6 are used.

On the photo 5, one can admire the machining of the cups, 3mm thickness which will resist to the trade winds i am regularly subjected.

Photo 447
small modification:
At the bottom of each telescopic element, i have added butterfly screw to block each elements between them. These bolts rest on the top of the lower tubes, they take part in the rigidity of the unit, avoid inoportune rotations due to strong wind, reduce work of the clamps which are not subjected any more to the vertical weight.

Photo447

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Photo448

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Photo 448
I have added a maintenance collar at the bottom end of the telescopic mast and inside the triangular Balmet tower section, while inserting between collar and aluminium tube, a rubber strip which limits the crushing of the aluminium tube during tightening, and could prevent the higher elements from returning downwards suitably.

Photo449

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Photo 449
Small modification:
Traction not being really strong, i carried out to the replacement of the stainless collars, to maintain the wire elements (radiators, reflectors and directors) with the boom by "Rilsan" plastic electrician collars.

Photo 452
The spiderbeam is fixed in its final place now, all tests will start from 2,50m height, then at 5m on the roof and at 9m on the roof or 12m above the level ground.

Photo452

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Photo450

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Photo 450
You can see visual reference mark with green/yellow ribbon for the boom and an arrow to indicate the radiation direction as well. By the way, it's a small idea to help everyone when you dont have any antenna rotator and useful when antenna is used in portable Dxpedition.

Photo 453
The Spiderbeam antenna is standing up approximately 5m above the roof and the adjustements recommended by Con/DF4SA prove to be real. At 9m high, i had a slight improvement but the adjustments do not change as much.

Photo453

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Photo451

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Photo 451
The balun box with the various connections wires of the feeding elements.
2 stainless collars firmly maintain the enclosure to the vertical mast.

Photo 454
The Spiderbeam antenna is now operational, the photo is not so good at sunset time. So, i will put some nice pictures as soon as weather will return in beautiful conditions.

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FK8DD 3bander Spiderbeam Initial Tests and measurements

Monday, 03rd of september 2007
FK8DD Tribander Spiderbeam Measurements at 9m on the roof
SWR direct measurements with MFJ-941E


20m Band
14000 khz => SWR:1.1, SWR is quite correct and needle climbs to 1.5 when going up in USB band near 14180Khz.
Without coupler, 20m bandwith is 320khz
13860 khz => SWR: 1.5---------->14020 khz => SWR: 1.1--------->14180 khz=> SWR: 1.5

15m Band
21000 khz => SWR: 1.8, measurement in SWR is very important when going up in USB band,
Without coupler, 15m bandwidth is: 200 khz (radiator will be tune as soon as possible)
20700 khz => SWR: 1,7---------->20750 khz=> SWR: 1.5----------> 20900 khz => SWR: 1.7

10m Band
28000 khz => SWR: 1,1, needle does move slightly when goinp up in USB bande, SWR climbs to 1.5 towards 28600 khz
Without coupler, 10m bandwidth is 900 khz
27700 khz => SWR: 1.5---------->28150 khz => SWR: 1.1----------> 28600 khz => SWR: 1.5


Below Technical characteristics of the Spiderbeam antenna by "Spiderbeam Team"



More details below on final tests and measurements for 3bander Spiderbeam antenna, done on 10th of october 2007


Final Tests and measurements

Monday 10th of october 2007
After Reajustment, direct measurement of 3bander Spiderbeam without tuner Box


20m Band

14000 khz => SWR:1.1, entire 20m band is correctly covered, till 14300 Khz => SWR: 1.5
No coupler needed at all.
Radiator had been shorten for about -4 cm, reflector and director left on original measurements.

15m Band
21000 khz => SWR: 1.1, entire 15m band is also correctly covered, till 21350 Khz => SWR: 1,5
No coupler needed at all.
Radiator had been shorten for about -2,5 cm, reflector and director left on original measurements.

10m Band
28000 khz => SWR: 1,1, entire 10m band is also correctly covered, till 28600 khz => SWR: 1.5
No need to reajust this band after 20m and 15m radiator tuning, SWR on 10m band does not change at all.
On 10m band, No coupler needed, as entire band is covered without any SWR problem.

Be careful for your own security !!

NB:
Constructing the Spiderbeam is a thing, we can undertake this operation by ourselves, but safety is much better with 2 people to erect this kind of antenna, because i can say having had a lot of fear and big frights during installation of telescopic mast and antenna.

Special Thanks to Spiderbeam antenna Team

Special thanks
well, i want to thanks the Spiderbeam antenna originators as
Con/DF4SA and his Team for this splendid antenna design, which is waiting to express itself on the air..! In the nearest future, i would like to transform my tribander spiderbeam into a 5 bands antenna...I know the work i have to do...anyway thanks so much to take on your sparetime for reading FK8DD new experiment on Spiderbeam assembly...So long everybody, auf widersen, KÚnavo, Adichat, Nana, Good bye, ce n'est qu'un Au revoir.

Sam FK8DD

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