Thursday, August 2, 2018

Repositioning a Hustler 6BVT

Looking at my Hustler 6BVT antenna the other day got me thinking. After four years  everything has grown, the antenna is certainly being surrounded by nature.
While building a stone slab base for a  new shed near to the Hustler, I noticed the ground radials I laid out all that time ago have started to break up,  I have already noticed broken wires that seem to be appearing all over the place!  
 It’s now sitting surrounded by hawthorn and apple trees some as high as thirty feet which can’t be good, I’ve noticed reception has gone down since I first installed it and I think it’s time I found the antenna a new home.
The present position of the Hustler and the area of the new shed, I think I'll put the antenna on the other side of the trees in the paddock.

Two things immediately spring to mind, where to place the antenna and installing the ground radials. The recommended number of ground radials is around 32 but I like to have at least a minimum of 40 radials, all different lengths to cover the bands.

Ground radials can be a black art in themselves, you can get away with as little as about 12 but it not always recommended unless you have very wet soil. When I first installed the hustler there were about 60 and they seemed to take forever to lay out, but it was definitely worth it. The ground plate was a home brew  effort, basically a piece of aluminium bought off Ebay with the holes drilled and then small bolts place in every other hole, I could then attach each wire or a combinations of joined wires to each bolt with a small nut, fairly basic but worked well and saved me some money.

 when I removed the ground plate wires were everywhere!
 One difficulty is that I am limited by coax length, the present RG58 coax which is connected to the hustler is buried under a large part of my garden and unless I dig it up and totally start afresh, I will only have roughly 30 feet of coax to play with for re- positioning. So I have a number of factors to work out, but I’m sure it will come good in the end.
If I lay out the exposed coax around the paddock area to see what exact length I have to play with, I should be near enough in line with the mini Yagi, but obviously I don’t want to get too close.
Then I'll start  laying out the ground radials in the full 360 degrees circle and see how that goes. I will begin with 12 radials but hopefully ending up with at least double. As I lay each radial I intend to mow the grass fairly short so I can pin each one in to the ground and so in future it won’t get mixed up with the mower blades. Hopefully within a few weeks the radials will have disappeared from sight by the growing grass.  I'll then reconnect the radial plate with its new radial system and then install the newly positioned antenna and test for SWR!
The cleaned up radial plate.

So I've  disconnected the Hustler from the ground radial plate and disconnected the old wires and given the plate a good scrub and it's come up reasonably well. Next week if I get the chance I'll clean and then replace the antenna in its new home and then think about putting out the new ground radials!
What fun, the first spot I placed the hustler I raised it up I was touching a telephone wire a 1 in a 1000 chance, typical! so I had to move further than I liked,  the only issues was adding some extra 15 feet of coax.

The 2nd move of the antenna went according to plan with little fuss and no more telephone wires in the way. A tip worth remembering is to make sure everything is well greased up or lubricated in some way, it makes dismantling so much easier, I was very surprised how everything came apart so easily, but this was due to me lubricating when first assembled! I've added about 6 ground wires so far and a small amount of wire netting, I'm not going to rush just take my time and add more ground radials as I go along.


So far the SWR is a good 1:1 across all bands but the important thing is the resistance which ideally should read around 36 but at the moment is a 45. I suspect by adding more radials (about 7 more) it will come down to around 38/40 and then as you add more it will slowly reduce but not by any great amount. The average is about 12 to 15 but obviously if you can add more it will improve. A few years ago I would be going beserk adding as many as I can but now I'm a little slower and I'm getting reasonable results so I'm taking things slowly!

With 4/5 ground radials! I shall add more as I go along. 
More importantly results on the radio using the Hustler are good. Obviously conditions and solar flux are not at their best but testing between the Yagi and the 40/80 W3DZZ things are looking up. With some more ground radials to be added it's looking good for its new home!


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