I am trying to build a 20meter 1/2wl end fed vertcal antena and havent had a
lot of success. The antenna is for use at maximum legal power so I need
componets in the network that will hold up. I have tried a J pole
configuration that I never was able to properly tune and I have tried lump
sum LC values that melted down with max power. I guess the last way is
doable but not unless I want to spend really big bucks on new HV capacitors.
I was thinking about the matching section on my Ringo Ranger. Why not just
scale this up for 20M? The mechanics of it arent a real problem, I can
fabricate most anything I would need. Seems like I've heard the mast for a
Ringo needs to be at least a 1/4 wl long, is this true?

Feed it through a 1/4 wavelength stub.

Jimmie D wrote:

I am trying to build a 20meter 1/2wl end fed vertcal antena and havent had a
lot of success. The antenna is for use at maximum legal power so I need
componets in the network that will hold up. I have tried a J pole
configuration that I never was able to properly tune and I have tried lump
sum LC values that melted down with max power. I guess the last way is
doable but not unless I want to spend really big bucks on new HV capacitors.
I was thinking about the matching section on my Ringo Ranger. Why not just
scale this up for 20M? The mechanics of it arent a real problem, I can
fabricate most anything I would need. Seems like I've heard the mast for a
Ringo needs to be at least a 1/4 wl long, is this true?

"Dave" wrote in message
. ..
Feed it through a 1/4 wavelength stub.

That was my first thought and I invisioned 16 ft of open wire line runing
out across the yard. But now that I think of it this may be a workable
solution. No reason it has to be stretched out straight, circle it around
the antenna. Hmm back to Ringo again.

Jimmie D wrote:

I am trying to build a 20meter 1/2wl end fed vertcal antena and havent
had a lot of success. The antenna is for use at maximum legal power so I
need componets in the network that will hold up. I have tried a J pole
configuration that I never was able to properly tune and I have tried
lump sum LC values that melted down with max power. I guess the last way
is doable but not unless I want to spend really big bucks on new HV
capacitors. I was thinking about the matching section on my Ringo Ranger.
Why not just scale this up for 20M? The mechanics of it arent a real
problem, I can fabricate most anything I would need. Seems like I've
heard the mast for a Ringo needs to be at least a 1/4 wl long, is this
true?

Jimmie D wrote:
"Dave" wrote in message
. ..
Feed it through a 1/4 wavelength stub.

That was my first thought and I invisioned 16 ft of open wire line runing
out across the yard. But now that I think of it this may be a workable
solution. No reason it has to be stretched out straight, circle it around
the antenna. Hmm back to Ringo again.

Have you tried using coax for the caps, same as the cushcraft ringos?
I'm not sure how much power a cap made from say 213 would handle,
but it going to be several hundred watts at the min.. I've built what
you
are building. It will work fine, and the height above ground is not
that
critical. But I eventually changed the antenna to be a 40 GP and a
5/8 GP for 17m. I used a relay to switch the loading coil for 17m
in/out.
The "gamma loop" for 20m is kinda large, so you need some stiff tubing
to hold stable. IE: copper tube, etc..
MK

Jimmie D wrote:
I have tried a J pole
configuration that I never was able to properly tune ...

Why did you give up before it was properly tuned?
--
73, Cecil http://www.qsl.net/w5dxp

"Cecil Moore" wrote in message
m...
Jimmie D wrote:
I have tried a J pole configuration that I never was able to properly
tune ...

Why did you give up before it was properly tuned?
--
73, Cecil http://www.qsl.net/w5dxp

Sold my antenna support, 3 story house.

Jimmie D wrote:
"Cecil Moore" wrote in message
Why did you give up before it was properly tuned?

Sold my antenna support, 3 story house.

The matching section for your 20m 1/2WL monopole can
be mounted horizontal if it is more convenient. FP
is where it connects to the 1/2WL vertical section.

+-----------X-----------16.5'---------------+FP
|
+-----------Y-----------16.5'----------------open


The coax connects at X and Y where the 50 ohm feedpoint
is located. #14 or larger wire will handle anything
legal that you can put into it. No high voltage capacitors
required. No lossy coils required.
--
73, Cecil http://www.w5dxp.com

"Cecil Moore" wrote in message
m...
Jimmie D wrote:
"Cecil Moore" wrote in message
Why did you give up before it was properly tuned?

Sold my antenna support, 3 story house.

The matching section for your 20m 1/2WL monopole can
be mounted horizontal if it is more convenient. FP
is where it connects to the 1/2WL vertical section.

+-----------X-----------16.5'---------------+FP
|
+-----------Y-----------16.5'----------------open

The coax connects at X and Y where the 50 ohm feedpoint
is located. #14 or larger wire will handle anything
legal that you can put into it. No high voltage capacitors
required. No lossy coils required.

Thanks Cecil This was my first plan but I dont have room to run the stub
straight out so I kind of tabled the idea for a while. Now that I have
thought about it there is no reason I couldnt wrap it around the antenna.
Talking with others sure helps the thought process. I still may play with
the idea of the 20M Ringo design. It would be a lot of fun telling people
you have a 20M Ringo Ranger. My only real problem with using the Ringo style
matching network is that I heard once upon a time that the Ringo utilizes
the mast as part of the radiator. The main thing I see the Ringo type match
has going for it is that it would be about half the size of a 16.5 ft stub
wrapped around the antenna

Jimmie D wrote:
Thanks Cecil This was my first plan but I dont have room to run the stub
straight out so I kind of tabled the idea for a while. Now that I have
thought about it there is no reason I couldnt wrap it around the antenna.

There's no reason why you couldn't spiral it around
the antenna like a pancake inductor. If you kept each
spiral about a foot away from the next one, the area
occupied would be pretty small. Good luck.
--
73, Cecil http://www.w5dxp.com

On Mon, 4 Sep 2006 15:23:37 -0400, "Jimmie D"
wrote:

I heard once upon a time that the Ringo utilizes
the mast as part of the radiator.

Hi Jimmie,

What was meant was that the mast inappropriately became part of the
radiator due to the design of the Ringo (which has had a reputation
for being a dummy load). The problem with half-wave designs is they
are high Z. Being high Z they are difficult to choke. Being
difficult to choke, they appropriate masts, supports, feed lines, as
additional radiation surfaces. When you add these lengths to the
radiator (and they are co-linear) then your radiation lobes begin to
climb into the sky (no one there to hear you) and the antenna becomes
deaf and dumb.

73's
Richard Clark, KB7QHC