Topband
[Top] [All Lists]

Topband: FW: Thoughts on making low resistance joints betweenaluminium t

To: <topband@contesting.com>
Subject: Topband: FW: Thoughts on making low resistance joints betweenaluminium tubing sections?
From: "George Stewart, VK5ALS" <ggstewart@adam.com.au>
Date: Thu, 31 Aug 2006 12:31:44 +0930
List-post: <mailto:topband@contesting.com>
Hi Topbanders,

With Edy's permission I am posting the reply he sent to me direct:
------------------------------------------------
Hello George, my two cents.
I had and experince with a very short antenna which
differs from other answer I found.
I think the problem relies if you go really short with
the antenna, and if you don't have any resistance in
your ground conection which will force all your RF
into your tubes.
I am using a very short rotary dipole on 80 meters,
7.5 mts each side (15 mts total), so here is no ground
resistance conection.
It is like a KLM for 40 mts but with a coil adition.
I had serious trouble with the aluminium joins after
the coil.

I tried using the grease, after sanding the tubes, 1,
and 2 stainless screw, but nothing work. I replaced
the tubes for new ones, but nothing change.

After a month or so of using 1KW, it fail at the
joint. producing severe rectification of closer
broacast.

I asked in some forums if someone has had that
experienced but nothing came.

After 8 months of trying all I could imagine, I
decided to solder the joints. It never failed again
since 12 years.

If you are not going so short or in case of a vertical
you have  little ground resistance, you might not
experince the problem.

Curiosly I never had that problem for 4 years with the
dipole operating on 40 mts, so current on 80 should be
really high.

I hope this help....'73... Edy, LU2DKT

_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband

<Prev in Thread] Current Thread [Next in Thread>
  • Topband: FW: Thoughts on making low resistance joints betweenaluminium tubing sections?, George Stewart, VK5ALS <=