"Desmoface" ... anyone think a verticle dipole
would work. ..a vertical dipole for 10...
Steve kb8viv

How about a J-Pole? ..one using a mast with the 1/4 wave
parallel section added 1/2 wave below the top. Real easy. No radials.
John Smith - KD5YI

As others have already noted, vertical dipoles do work
whether center-fed or end-fed (a.k.a. J-pole) without radials.

As already noted, hang it as high as you can manage
- just the normal advice for any antenna except N.V.I.S.

If you want to pursue the J-pole route,
go to CQ magazine's web site

http://www.cq-amateur-radio.com/

and download George VE3ERP Murphy's freeware HAMCALC
ham radio software package. (lower left corner)
(Download it just for general principles.)
Program about-23 of 250+ programs
is Murph's version of my version of Gary N3GO O'Neill's
J-pole program from his Communication
Quarterly article on end-fed half-wave antennas.
Go to Steve AA5TB Yate's website

http://www.qsl.net/aa5tb/

under "Antennas" for more info and a link
to Gary's article on how J-poles
and Zepps really work versus the popular view.

The program gives starting lengths.
For 28.5 MHz:
Using 300 ohm twinlead:

halfwave radiator wire = 196.7 inches
series matching 300 ohm section = 78.6 inches
to the 50 ohm tap point
shorted shunt stub 300 ohm section = 6.6 inches

Total length is about 23.5 feet if you hang it all up
vertically. The not-quite-quarter-wave matching section
can be horizontal with the halfwave radiator vertical
if you need/want to run it that way.

Gary's article, the program or a Smith chart show
why the commonly used 450 ohm ladder line is not
the as good a choice for matching as 300 ohm.

Have fun. Measure and cut metal and plastic,
hang it up, apply and withdraw RF energy.
Don't just do computer calculations
(as I do most of the time (sigh)).

Cheers, 73,

Ron McConnell



N 40º 46' 57.9" W 74º 41' 21.9"
FN20ps77GU46 [FN20ps77GV75]

http://home.earthlink.net/~rcmcc

On 08 Jan 2004 18:51:02 GMT, (Desmoface) wrote:

Hey kids..I know gap kind of does this..but anyone think a verticle dipole
would work...basically a vertical fed in the center...Im wanting a good 10
meter antenna for local stuff and was thinking about a conventional
vertical..than I thought maybe I could do without the radial system and ground
loss issue but just putting up a vertical dipole for 10...any thoughts??

Steve
kb8viv

Cebic has a whole page of 10-10 antennas:

http://www.cebik.com/a10/anta.html

Bob
k5qwg

(Desmoface) wrote in message ...
Hey kids..I know gap kind of does this..but anyone think a verticle dipole
would work...basically a vertical fed in the center...Im wanting a good 10
meter antenna for local stuff and was thinking about a conventional
vertical..than I thought maybe I could do without the radial system and ground
loss issue but just putting up a vertical dipole for 10...any thoughts??

Steve
kb8viv

You could base feed it with a gamma loop type matching device. For
10m, the single turn loop would be appx 9-11 inches dia. The cap can
be an appx 16 inch length of coax. You need appx 50 pf or so to match
for 10m. I've built many of these for the higher HF bands. They work
well, and are easier to tune than it sounds. The cushcraft AR-10 is a
commercial version of this antenna, using that type matching device.
You can get a PDF manual on their website. Heck, you might just want
to buy a AR-10 and be done with it... They are fairly inexpensive.
They are also easy to butcher up and make other antennas from. I've
modified many of those for other uses. MK

"Desmoface" wrote in message
...
Hey kids..I know gap kind of does this..but anyone think a verticle dipole
would work...basically a vertical fed in the center...Im wanting a good 10
meter antenna for local stuff and was thinking about a conventional
vertical..than I thought maybe I could do without the radial system and
ground
loss issue but just putting up a vertical dipole for 10...any thoughts??

Steve
kb8viv
you can easily build a Dipole.. but for the hastle.. are not such things
just as easy to buy?
Suggest you take a look at the local CB shop. There are 1/2 wave dipoles
available here in the UK for less than £20 ($35 US) All you need to do is
make the antenna shorther than it would be for CB, (appx 8 1/2 feet per
side).
http://www.geocities.com/Augusta/7117/antenna.html may be of use to you..

Robin