Hi whatever your name is,

I am puzzled. If, as you wrote, John corrected you on the 'fact' that he
did not "Invent" these Antennas or the Design Concepts of these Low Noise
Antennas, then presumably he told you who did. So why have he and you
neglected to mention that in your writings?

It was Denzil Wraight, in fact, who rediscovered Strafford's work on noise
reducing antennas, and who discovered by trial and error reasonable turns
ratios for the antenna matching transformers (Strafford does not discuss
that in his articles). So it is Strafford and Wraight that Doty plagiarized
and you failed to cite. Denzil used a vertical noise reducing antenna,
wrote me about how well it worked, and included a copy of Strafford's
Wireless World article. First I constructed a "top fed" vertical version
with mast almost touching my house. I didn't expect it to do much fow man
made noise in the MW band (my main interest), but to my surprise it did. In
my case, there was little, if any, difference noise reduction between
mounting the vertical mast almost touching my house, or 100 feet away. So
this kind of noise reducing antenna is ideal for DXers with limited space.
Next I implemented an inverted L version of Strafford's noise reducing
antennas. If I recall correctly, the first L was about 100 feet horizontal
and 15 feet vertical. I experimented with both base feed and top feed.
Both gave excellent noise reduction in the MW (and VLF) band(s). Both
Denzil and I used twin feed instead of coax because twin feed tends to pick
up less local nois than coax. Denzil and I wrote two separate articles for
DX news (The National Radio Club http://www.nrcdxas.org/ reprint A69) that
were published in the early summer of 1991. I had sent Mark Connelly
preprints of our arfticles, and he developed coax feed versions of
Strafford's noise reducing antennas. According to Mark, the coax feed
variant picked up little, if any additional noise compared to the twin feed
version. At one point in these experiments I tried shielded twin lead, but
found no further noise reduction (or increase).

Presently I use top fed inverted L noise reducing antennas as parts of my
phased arrays. Unless you are listening above 16 MHz or so, or have an
insensitive receiver, you don't really need (or want) a big inverted L. Mine
are 15 feet up and 30 feet horizontal. The matching transformer we
used then (and which I still use now) is an Amidon FT-114-75 (the 75
material may have been replaced with J material), 43 turns to 9 turns (at
the center of the 43 turns) #20 enameled copper wire. The twin lead I still
use is Radio Shack speaker wire (#18 stranded, 7 strands of, I think, #26).
It is cheaper ane easier to use than real twin lead, and had about the right
characteristic impedance (about 100 ohms). You'll need a balun (1:1) at
your receiver to convert the balanced lead in to your unbalanced receiver
antenna input (9 bifilar turns of #20 enameled on an FT-114-75 will do).

Like I said before, the noise reducing properties of these kinds of antennas
begin to decline as you go higher in frequency, and above 6 MHz there is not
much noise reduction. If you believe you got substantial noise reduction
above 6 MHz due only to using one of these kinds of antennas, then you are
mistaken. For SW, Strafford recommended doublet antennas for noise
reduction. I do not have much experience with these because I am not much
of a SW listener. What little experience I have suggests that phased arrays
are much more effective at reducing SW noise sources. Unfortunately,there
are no good phasers that you can buy.

As for publishing these articles on the web, that would involve considerable
work. The articles were produced with typewriters, and contain hand
drawings. To convert them to .PDF or other files would be non-trivial, and
would require NRC approval. Anyone who wants these articles can easily
purchase them as reprints from the NRC at the web site above using PayPal or
other methods of payment.

Best regards,

Dallas

"RHF" wrote in message
oups.com...
DALLAS {aka: AEN} ,

Long ago John Doty corrected me on the 'fact' that he did not "Invent"
these Antennas or the Design Concepts of these Low Noise Antennas.

However, within this Forum {Rec.Radio.Shortwave} his 'articles'
{Writings} and his 'name' are/is the most often cited reference
concerning this topic.

This is why I say {write}
"Low Noise SWL Antenna" using the 'design concepts' that were
popularized by John Doty.

READ - Three "Must" Links to Read -wrt- Low Noise SWL Antenna
http://groups.yahoo.com/group/Shortw...na/message/949

NOTE: John Doty's 'articles' {Writings} and his 'name' are/is
available freely on the Web (WWW) and thus Millions may View and Read
them.

AEN - ? Have you consider 're-printing' your 'articles' {Writings} on
the Web (WWW) and making them Free for All to View and Read ?

AEN - Doing so, may provide you with the recognition that you so justly
deserve.

TBL: As to whether, the "Low Noise" Antenna 'design concepts' work
well for Shortwave Listener (SWL) Antennas: They have improved my
Shortwave Listening with good signal levels and much lower noise. What
more can I say: "I Ain't No Elmer !"

Enjoy Listening to your Radio/Receivers with your Antennas.

iane ~ RHF
.
All are WELCOME at the Shortwave Listener (SWL) "Antenna Ashram"
http://groups.yahoo.com/group/Shortw...na/message/502
Some Say: On A Clear Day You Can See Forever.
I BELIEVE: On A Clear Night . . .
You Can Hear Forever and Beyond, The BEYOND !
[ With the a SWL Antenna of your own making. ]
.
.