I screwed up and sent the reply to the gw micro list.  Let me try this 
again.
From [log in to unmask] Mon May 14 18:51:43 2007
Date: Mon, 14 May 2007 11:51:40 -0700 (PDT)
From: Butch Bussen <[log in to unmask]>
Reply-To: [log in to unmask]
To: [log in to unmask]
Subject: Re: My Apologies

The thing to remember is the formula is a bit different depending on whether
or not you're figuring out the length of a dipole versus say a half wave
length of a certain feed line.  Be cause of what is called "end effect", the
actual working length of a dipole is 5 percent less than an actual half wave
length.  If I were going to make a dipole, I'd make a folded dipole out of
twin lead which use to come with a lot of tuners. You come out around ten
feet, and you then multiply this by the velocity factor of the twin lead.  I
think most of this stuff is going to be around .88.  Been a long time since
I did this stuff.  Anyhow, but the length you want, short each end and cut
one side in the middle or center of the dipole.  Your feed line goes here.

The antenna formula we use to use was 468 divided by freq in mhz to give you
length of a half wave dipole in feet.  If you're figuring a tuning stub,
you'd actually use 492 divided by frequency as there is no "end effect"
here.  You then multiply this figure by the velocity factor of the coax.
Most is .66 although foam is around .8 as I recall.

You can do some cool stuff with tuning stubs.  The gap vertical I have uses
one in a unique way I hadn't thought of until I put up this antenna. As we
all know, to effectively lentghen an antenna, you need to add
inductance--put it in series.  The gap uses a capacitor.  What they do is
put the cap at the end of a quarter wave stub which basicly makes it look
like an inductor as far as tuning.

Another trick I use to use was back in the cb days when I was servicing and
selling cb radios.  Many of my customers ran 102 inch whips--q quarter wave
on 27 mhz.  Problem was in the dirt and snow storms we got back in Kansas,
the static electricity would build up to the point where you could watch it
jump from the center pin of a pl 259 to ground.   Imagine what this did to
most fet rf amplifiers.  A simple fix was to put a t connector at the radio
and hook the antenna feed to one side, and a shorted quarter wave stub on
the other side.  A quarter wave stub shorted looks open at the frequency it
was cut for, and an open stub looks shorted.  AS far as the swr or antenna
impedance on 27 mhz, the stub didn't exist, but at other frequencies it
provided a short and a dc path to ground.

Enough rambling for now.
73s
Butch Bussen
wa0vjr