[Lowfer] LIP

[Les Rayburn]

At 09:46 PM 1/20/02 -0600, Lewis Denton wrote:

>God Bless America
>Hi Les,
>    Thanks for the interest,
>I am using a 50' vertical with about 8' top hat,  single ground rod. I don't
>have any means of measuring antenna current, I tune up using a field
>strength meter, 200 Micro amp dc meter with diode and resonance L C circuit
>and a 4' whip.
>I use a AM broadcast antenna  ferrite rod with added turns to for the
>induction.
>I am not able to go to QRSS30 or 60 at this time, looks like i need to order
>me another controller IC from K1el, i think that is where i got the one i
>have now.
>my final current is 60 ma. at 17 V.
>Lewis
>Lip


Lewis,

It sounds like you've got a good installation started. The 50 foot vertical is
nice...height being the most important factor in any Lowfer antenna. If I might
make some suggestions?

The ground system is sub-par. You'll need to lay down at least 12-24 radials...
perhaps in a counterpoise arrangement like I'm using now.

Also ferrite rod coils have proven to be very ineffective on LF. They tend to
saturate with any kind of antenna current at all and produce losses. I'd 
recommend
winding a good air core inductor. I actually have a litz wire coil wound on
an oatmeal box that I could send you. It has lots of taps though, and is not
really the best choice. Better would be to wind one without any taps, using
a variometer for fine tuning.

Then going to QRSS30 or QRSS60 would help. Usually an antenna current
of around 110-125ma is required for successful skywave reception. So you're
close to making the jump!

My counterpoise has performed way beyond my expectations this year. It is
mounted literally under my deck. I simply stapled the wires under the deck
joists, and tried to completely cover the area under the antenna with wire.
It is far from the "perfect" model the textbooks mention, but it has resulted
in 1,500+ mile receptions and it works great on the ham bands too.

I'm surprised that "stealth" counterpoises are not more common. I did see
some faint traces of a signal on your frequency early this morning at around
06:40AM CST. But it could have easily just been noise too. Keep at it
and I'm sure that you'll make the trip here regularly soon.

73,

Les Rayburn, N1LF





Les Rayburn, director
High Noon Film & Interactive
100 Centerview Drive
Suite 111
Birmingham, AL 35216
(205) 824-8930
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http://www.highnoonfilm.com