Mike, the tuner was not designed for 400 Ohms and you won't see any
noticeable difference.
Once you get to the shack with your openwire, you need to run it through
some sort of a balun to the tuner, OR you can use the built-in balun, WHICH
I DO NOT RECOMMEND.
Instead, use an external 1:1 tuner "if" your primary focus is the low bands.
I prefer the ugly balun (Bob and I call it the Monster Balun), which is coax
wrapped on a huge piece of PVC pipe, with the turns of the coax separated by
1/4 inch rope.
Here you can see a picture of mine: http://www.dj0ip.de/balun-pictures/
(It's the top balun in this picture.)
Of course you can do better, using coax wound through several toroids, but
it is bigger and bulkier.
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Mike Bryce
Sent: Thursday, July 11, 2013 6:07 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] OCF antennas evolution
Gang,
I'll have to jump in here, too.
I remember reading in one of the antenna books that some guy, to prove a
point, worked DXCC using a light bulb as an antenna.
But...
Several years ago I homebrewed a OCF dipole with a 4:1 balun and stuck it up
a tree. I've had nothing be outstanding results without a tuner. I won't
cover 30 meters, but what the hey.
There is currently a large antenna/tower project in the final stages at this
qth. One of the antennas I plan on installing is a 260 foot doublet feed
with 600 ohm open line feeders
Now, I wonder how much of a problem my 238 tuner will have with the 600 ohm
line instead of the 400 ohm the tuner had been designed for?
Mike Bryce, WB8VGE
the heathkit shop
SunLight energy systems
J e e p
o|||||||o
On Jul 11, 2013, at 11:29 AM, Carter wrote:
> On 7/10/2013 11:33 PM, Michael Tortorella wrote:
>
> > I feel compelled to weigh in here....back in the late '70s I used an
> > OCFD design from Ham Radio magazine which was pretty straightforward.
> > It was 135' long, fed with 44' of 300-ohm open wire to a 4:1 balun
> > and then a run of RG-11 into the shack. It was superb. Never had any
> > stray current problems. Worked about 150 countries using a Johnson
> > Navigator, 40 watts input. Would like to reproduce that next time
> > out. Don't pooh-pooh the OCFD design, be careful and it works well.
> > 73 Mike W2IY
>
> I smile when I see everybody describing their favorite wire antenna,
> so let me jump in with my comments (asbestos suit on). <grin>
>
> Mike, not to deny your success nor picking on you or anyone else
describing their favorite wire antenna...but with ANY antenna, the RF has to
go somewhere.
>
> I'm using a dipole about 130 feet long and maybe 25 feet off the ground
fed entirely with ladder line (and a Johnson Matchbox) and worked a LOT of
DX including Indonesia on 80, the VK0IR dxpedition and even North Korea on
RTTY with that antenna.
>
> Heck, Kurt N. Sterba wrote in 'World Radio' magazine that he used a
SHOPPING CART as an antenna during a DX contest and worked 17 countries!
Again, the RF has gotta go somewhere.
>
> Bottom line: DX performance seems more attributable to the Propagation
gods rather than what flavor of wire antenna is being used.
>
> 73,
> Carter K8VT
>
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>
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