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Old January 3rd 10, 09:35 PM posted to rec.radio.amateur.antenna
Lostgallifreyan Lostgallifreyan is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 613
Default Sangean ATS-909 external antenna impedance??

Richard Clark wrote in
:

On Sun, 03 Jan 2010 14:19:05 -0600, Lostgallifreyan
wrote:

Burying anything out there is harder work than
sinking a ground rod. I think I'm going to have to take my chances.


Consider the significance of "shallow" inches, not feet; and sometimes
barely beneath the surface if you have to. If you don't have to (no
trip hazards to worry about) on the surface is equally suitable. You
don't need bare wire, but you can use it - it doesn't matter.

Radials need only be as long as your vertical is high. 16 to a couple
of dozen are sufficient.


I won't have scope for that much but I can certainly run a few longer ones on
unpaved ground alongside walls if that helps. I've thought about doing that
anyway.

Even if I add a little salt water or dilute acid to accelerate that?
This is something I've been considering..


Don't go there. Curing takes years and is an issue of soil
compaction.


Ok. I intend to use one of those drills that have a hammer action without
runing, to push the rod in. If I find a rod with a slight taper that would
help.

By choking the feedline, do you mean
placing ferrite slugs round it like those used on VDU cables? That's
something else that will be cheap and easy to test empirically.


That is exactly one very good solution. You need to research the
appropriate ferrite mix which is frequency specific when we are
talking about huge swaths of LF to HF coverage.


I will, I've already been looking into that so I don't have to blindly hunt
for some toroid by make and model number.. I notice the US has much easier
access to high permeability materials than the UK does, but no idea why this
is so. I saved a couple of PDF's with tables of frequency ranges vs materials
used.

There looks like one difference. Any signal hitting a coax screen if
used in this scheme will have a corresponding return current in the core
wire,


This one statement exposes a very large problem in understanding about
the physics of coaxial cable.

The equality of nature in each half of a twin wire appeals
to me, so long as it actually works. Should be cheap and easy to test
that one...


Actually, it is harder than you might imagine at first glance. Yes,
the methods are simple, but getting past preconceived notions is the
single greatest hurdle. Many engineers are ill suited to the task.


Try me. All it needs is a clear statement that I can relate to something
I've already experienced. I'm well used to being cautious about what I learn.
Unless it's as tough as atomic physics, it should be digestible, even if
slowly. And I won't be able to taste it till tomorrow... got to sleep soon.
Thanks for this, it encourages me to take the time when others do.

73's
Richard Clark, KB7QHC