Does anybody have a recommendation for a good book or journal article on
very short antennas? I'm trying to design the front end for a LF/VLF
receiver and would really like to know the equivalent circuit for
antennas ( both E-probe and loop ) a tenth of a wavelength or less.

I've Googled around and looked at a couple of lowfer web sites. Lots of
cookbook stuff and some approximate formulas for radiation resistance,
etc. but I haven't seen a real definitive treatment of this subject.

What about the oldie-but-goodie book by Kraus? Is that worth investing
in, or is there anything newer or better?

Thanks for any info.

-vs-

On Sun, 27 May 2007 14:33:24 -0400, "Virgil Smith"
wrote:

What about the oldie-but-goodie book by Kraus? Is that worth investing
in, or is there anything newer or better?

Hi Virgil,

Newer? Frequently, and accompanied by some astonishing claims.
Better? They can't even explain it themselves (although that doesn't
lower them on the Beaufort scale of gusting on).

As you are familiar with Kraus and have done some detective work, it
is unlikely you will find any surprises that diverge from the classic
discussion (it consumes all of a page or two in most books).

73's
Richard Clark, KB7QHC

"Antennas for all applications" by John Kraus and Ronald Marhefka has a good
reputation.

Also look at "Small Antenna Design" by Douglas Miron. This book looks at the
limits of small antennas and contains a lot of info about modelling antennas
using NEC.

Virgil Smith wrote:

...

Sometimes, all you need is one page ...

http://www.untenna.com/tech.html

Especially interesting is:
Building the helix from tubing instead of fine wire reduces conductor
resistance, increases its bandwidth and gives it a rigidity that makes a
plastic support unnecessary. Figure 4 shows a helix design. With the use
of a big diameter winding and a shunt feed, the top hat and matching
networks are not needed. The use of tubing, a large diameter and a shunt
feed reduces conductor losses to a point where the short helix’s
efficiency exceeds that of loaded whips. The helix’s rigidity eliminates
signal strength variations that may be caused when whips flex.

The above taken from the page ...

Regards,
JS

If by any chance you can read German, I recommend _Kurze Antennen_ by
Gerd Janzen (DF6SJ). Even if you can't, you can get a lot from the many
equations, diagrams, and graphs.

It's a shame that Gerd has never been able to find a publisher that
would give him a fair deal for publishing this or his other excellent
books in English.

Roy Lewallen, W7EL

Virgil Smith wrote:
Does anybody have a recommendation for a good book or journal article on
very short antennas? I'm trying to design the front end for a LF/VLF
receiver and would really like to know the equivalent circuit for
antennas ( both E-probe and loop ) a tenth of a wavelength or less.

I've Googled around and looked at a couple of lowfer web sites. Lots of
cookbook stuff and some approximate formulas for radiation resistance,
etc. but I haven't seen a real definitive treatment of this subject.

What about the oldie-but-goodie book by Kraus? Is that worth investing
in, or is there anything newer or better?

Thanks for any info.

-vs-

"Virgil Smith" wrote
Does anybody have a recommendation for a good book or journal article
on very short antennas? I'm trying to design the front end for a LF/VLF
receiver and would really like to know the equivalent circuit for
antennas ( both E-probe and loop ) a tenth of a wavelength or less.
________

Lately I've been working on an Excel spreadsheet to calculate the parameters
associated with electrically short, MW/LF/VLF, v-pol antennas -- including
their inverse distance groundwave fields at 1 km and somewhat beyond,
subject to their specific groundwave propagation loss. The equations are
those found in an I.R.E. publication of the pioneer broadcast consultant
Carl E. Smith, and in REFERENCE DATA FOR RADIO ENGINEERS, published by IT&T.

Here is a sample screen clip:
http://i62.photobucket.com/albums/h8...Parameters.gif

Please let me know if you'd like to try it out. My e-mail address and
website are shown in the upper right corner of the clip linked above.

RF

Thanks to all who replied to my query. I now have several good leads which
I'll be following up. Cheers,

-vs-


"Richard Fry" wrote in message
...
"Virgil Smith" wrote
Does anybody have a recommendation for a good book or journal article
on very short antennas? I'm trying to design the front end for a LF/VLF
receiver and would really like to know the equivalent circuit for
antennas ( both E-probe and loop ) a tenth of a wavelength or less.
________

Lately I've been working on an Excel spreadsheet to calculate the
parameters associated with electrically short, MW/LF/VLF, v-pol
antennas -- including their inverse distance groundwave fields at 1 km and
somewhat beyond, subject to their specific groundwave propagation loss.
The equations are those found in an I.R.E. publication of the pioneer
broadcast consultant Carl E. Smith, and in REFERENCE DATA FOR RADIO
ENGINEERS, published by IT&T.

Here is a sample screen clip:
http://i62.photobucket.com/albums/h8...Parameters.gif

Please let me know if you'd like to try it out. My e-mail address and
website are shown in the upper right corner of the clip linked above.

RF

On 28 May, 10:02, "Virgil Smith" wrote:
Thanks to all who replied to my query. I now have several good leads which
I'll be following up. Cheers,

-vs-

"Richard Fry" wrote in message

...



"Virgil Smith" wrote
Does anybody have a recommendation for a good book or journal article
on very short antennas? I'm trying to design the front end for a LF/VLF
receiver and would really like to know the equivalent circuit for
antennas ( both E-probe and loop ) a tenth of a wavelength or less.
________

Lately I've been working on an Excel spreadsheet to calculate the
parameters associated with electrically short, MW/LF/VLF, v-pol
antennas -- including their inverse distance groundwave fields at 1 km and
somewhat beyond, subject to their specific groundwave propagation loss.
The equations are those found in an I.R.E. publication of the pioneer
broadcast consultant Carl E. Smith, and in REFERENCE DATA FOR RADIO
ENGINEERS, published by IT&T.

Here is a sample screen clip:
http://i62.photobucket.com/albums/h8...ennaParameters...

Please let me know if you'd like to try it out. My e-mail address and
website are shown in the upper right corner of the clip linked above.

RF- Hide quoted text -

- Show quoted text -

Virgil,
You wasn't quite clear as to what short antennas means!
For instance it could refer either to element length as well as boom
length. You will not lose much gain on elements that are shortened
such that the current curve changes to a triangle shape. With respect
to boom length
booms can be shortened quite a bit over yagis by using the
Gaussian design where the elements are placed close to planar. Normal
Gaussians of this style go upto 13 dbi for much less than a 20 foot
boom length when using just three elements tho you could go upto 6
elements on such a boom length. I think that there should be a spec
for "turning radius that would meet your quest as there is so much
confusion with respect to gain versus boomlength or number of elements
which is based solely on the yagi design to the ommission of other
designs.
Art

"Virgil Smith" wrote in message
. ..
Does anybody have a recommendation for a good book or journal article on
very short antennas? I'm trying to design the front end for a LF/VLF
receiver and would really like to know the equivalent circuit for
antennas ( both E-probe and loop ) a tenth of a wavelength or less.

I've Googled around and looked at a couple of lowfer web sites. Lots of
cookbook stuff and some approximate formulas for radiation resistance,
etc. but I haven't seen a real definitive treatment of this subject.

What about the oldie-but-goodie book by Kraus? Is that worth investing
in, or is there anything newer or better?

Thanks for any info.

-vs-



It seems to me the parameters you consider important would be very site
specific and a rx front-end optimised for a particular antenna may have to
be designed after taking empirical measurements for a specific antenna.
Otherwise IMO the cookbook information would probably be sufficent.

I am curious as to what you would consider a definitive treatment of the
subject as it pertains to rx front-end design.

Jimmie