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CHAPTER 7

Receiving Antennas


Tom, W8JI, is
my antenna guru,
my technical
guru, and he’s a
great friend to
have. I have read
everything he’s
published in his
Web pages or on
the Topband
Reflector at least
a few times. Tom not only has the knowledge, he’s got
the expertise and he uses it. He uses it to build the best
Topband station of the US South. His contesting and
DXing results are the proverbial proof of the pudding. But
what I admire most about Tom is his missionary ap-

Some of the Questions I Will Try to
Answer in This Chapter:







Why do we need separate receiving antennas?
What is noise? How to eliminate noise.
Are Beverages so superior?
Is a longer Beverage better?
How about vertical receiving arrays?
What’s the correct way of feeding special receiving anten­
nas?
• Can I do as well from my city lot as the big guns from their
rural farm?
• Are Flags, Pennants and K9AY loops an alternative to
Beverages?
• Why not receiving arrays with parasitic elements?
• When will we have receiving arrays with “active”
antennas?
In an e-mail K9RJ wrote, “The challenge of 160-meter
(Low Band) DXing is receiving. It should be no surprise that
the highest DXCC totals on this band are achieved only by
those who have the space for good receiving antennas, or who
live in a location where much of the DX is close by. I’m not
aware of any exceptions to this. Thus, the greatest need is for
creative development of low-noise directional receiving an­

proach: He wants technically better hams. The introduc­
tion on his Web site says it so well: “The most important
thing any of us can do to make the Web an asset is to
help each other with review to insure technical accuracy
IMPROVES with time! Let’s work to make Internet a
reliable source of information instead of a collection of
folklore!! … Like you, I also learn new things every day. As
my knowledge improves, I revise technical articles. I’ll note
revision dates on articles with changes, if the changes
affect technical content.”
No technical question is too difficult for Tom, not even
godfathering the chapters on special receiving antennas
and on phased arrays. I know Tom regretted he could only
spend a hundred hours or more reviewing these chapters… It indeed is an honor for me to have him help me
with the Fourth Edition of this book.

tennas or techniques such as active noise canceling that can
be used to improve receiving capability.”
Not so long ago, any mention of “receiving antenna”
usually invoked thoughts of “Beverage Antennas.” The evo­
lution in all technical fields is staggering, and it includes
receiving antennas. Not that something spectacularly new has
been invented, but our ability to communicate worldwide at
leisure has improved drastically thanks to the Internet. Tech­
nical knowledge is spread more easily, and technical discus­
sions have become accessible to nearly everyone interested.

1. INTRODUCTION TO RECEIVING ANTENNAS
This chapter no longer is a Beverage-only chapter. Un­
like previous editions, it will not even start with Beverages.
Readers have asked for more receiving antennas, so here they
are! However, before we get into describing receiving anten­
nas and antenna projects in detail, it is important to understand
a few basics.

1.1. Why Separate Receiving Antennas?
Separate antennas are necessary because optimum
receiving and transmitting have different requirements. For a
Receiving Antennas

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