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Gary Schafer
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Default SSB Antenna theory

I take it that you are trying to learn and not just be argumentative.

If you read what I wrote, I said that in the antenna handbook that
they finally have it right.

Read the first three paragraphs under "TUNING TO A QUARTER WAVE"


On Fri, 30 Apr 2004 00:07:54 -0400, "Doug Dotson"

First you cite several instances that the ARRL treatment is
wrong. Then you say the they finally got it right. Where are
your references that substantiate either statement?

Doug, k3qt
s/v Callista

"Gary Schafer" wrote in message
.. .
I tried to give an abbreviated synopsis of the subject and dispel some
myths. I did not cover all the details.

You need look no further than the ARRL itself for references. If you
read the whole post you would see that near the bottom I credited the
ARRL 2000 edition of their handbook, antenna section. The definition
of "radiation resistance" is from there and the calculations of the
example antenna with impedance's and voltages developed are directly
from there.

If you also look in the 18th edition 1997? of the ARRL antenna
handbook chapter 16 "mobile and marine antennas", and probably later
versions, you will see where they properly discuss loaded short
antennas and what the coil does.

Also if you look at the earlier post titled "Notes on short SSB
antennas" you will find a reference to W8JI's web site where he
discusses these very items in detail. He and many other engineers will
tell you the same thing.

I don't mean to discredit the ARRL but their statements in regard to
tuning an antenna to a quarter wave in their older publications are
misleading as evidenced by all the misconceptions that fly around.

While that is a simplified explanation of what happens with the
antenna matching, I suppose it was easier to propagate that (no pun
intended) term for simplicity. But if you really want to understand
what is going on it will get you into trouble in understanding as it
is a conflict with what really happens.


On Thu, 29 Apr 2004 20:25:53 -0400, "Doug Dotson"

So, is this something you put together? How about some references?
ARRL is a pretty reputable outfit. If you are going to dispute their
writings, you should provide some some verifiable references.

Doug, k3qt
s/v Callista

"Gary Schafer" wrote in message
.. .
This tries to explain how short SSB antennas operate and why.
The discussion is concerning antennas that are shorter than a quarter


I looked through several older handbooks and antenna handbooks and
found most of them professing what Larry is saying about "tuning an
antenna to an electrical quarter wave."

No wonder so many people have it wrong! The ARRL has been preaching
this stuff for years. But in the same paragraphs they will speak to
the "electrical length being very close to the physical length". Can't
have it both ways! Even the 2000 ARRL handbook has it wrong.

They finally got it right in their antenna handbook. Not once did I
see reference to "tuning an antenna to an electrical quarter wave

It may seem like semantics but there are a lot of people that get
confused and think that when making the system resonant with a
shorter antenna that the antenna is really the same as a quarter wave
length antenna when there is a loading coil. It is far from that. Its
radiation resistance and its feed point resistance are both much

An antennas electrical length is what it is by itself. Adding a coil
to it to make it resonant will not change that.