[Elecraft] [Antenna launcher

[Gary Smith]

Nice web pages. 

I discovered a couple of things that to me are important when it came 
to launching these projectiles to get wires over the tops of trees:

- A heavier weight is better than a lighter one such as a tennis ball 
when a 50 pound fishing line is attached, because a light weight 
object will get hung up on branches and the inertia from a heavy 
object falling to earth will bore its way straight through the 
branches and leaves. I painted the white PVC with red spray and on 
one I used red/white reflective tape. This makes it easy to find 
where it's landed in both summer and winter.

I ended up using 50 pound test monofilament line because the amount 
of branches I have to contend with end up being enough friction 
resistance that I was breaking lighter line. With the 50 pound test 
line I can bring my WD 1A telephone wire up and through the branches 
in one attempt. 

- a long barrel is far preferable to a short barrel because the 
addition of the eye on the end of the barrel prevents the line from 
flailing as it is being expended. If you try throwing a fishing line 
without a pole & the eyes to guide the line coherently as it's being 
expended, you will not throw it far. Attach eyes to a broomstick & 
lightly toss & it will go much farther. The eye is a must if you want 
distance. 

- In addition, a longer barrel will give you a greater distance, just 
like a rifle will shoot farther than a pistol with both using the 
same ammunition.

- When putting the PVC spud in the barrel, the line & swivel end goes 
in first, otherwise the drag from the line will make the projectile 
and invert on the way up spin like a top. That can be problematic 
when coming down as you don't want it to get hung up on top branches 
and if it's spinning like a propeller, it will hang up sooner than 
later.

FWIW, With no line attached I can shoot a 4" long projectile well 
over 1/4 mile of water without touching water. With the line attached 
such distance is quite impossible thanks to the drag, even with the 
eye in place. 

I figured I'd mention this tool here because of so many people on the 
Elecraft reflector enjoying remote operations with their QRP gear, 
this will help tremendously with the antenna end of things.

73,

Gary
KA1J

> On Mon,2/9/2015 12:07 PM, Gary Smith wrote:
> > To get a wire over the tallest tree on the first attempt and that
> > includes a Redwood, look at what I do at the bottom of my QRZ page. I
> > got the idea from a QST article a few years ago and then built on the
> > idea.
> 
> http://www.antennalaunchers.com/antlaunching.html
> 
> When I first moved to CA in 2006, K2RD brought one of these over to rig 
> my 80M dipole. His first shot cleared the tallest redwood on my property 
> by at least 25 ft. That tree is about 180 ft tall.
> 
> Here's another useful launcher for lower heights -- up to about 100 ft. 
> Buy it with the Zebco reel and attachment, and 10-12 oz throw weights.  
> You could use your own weights (fishing sinkers, for example), but these 
> throw weights are brightly colored cordura bags that make it much easier 
> to find on the ground after you've thrown them. My Chicago club owns one 
> that we used on Field Day and that was loaned to members to rig their 
> antennas.
> 
>   http://www.sherrilltree.com/Big-Shot-Standard-Kit#.VNkWwCvF_wk
> 
> 73, Jim K9YC
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