Thanks Rick,
I will try his solution tonight if I can get home before dark.
Tom
On Mon, Feb 14, 2011 at 3:40 AM, Rick - NJ0IP / DJ0IP <Rick@dj0ip.de> wrote:
> Tom,
>
> Here is a probable fix for 40m.
>
> If you have any of the commercial 450 ohm ladderline, use it and add 13 ft.
> of line to the antenna.
> I assume you can run it inside your shack, which is why I say to use
> commercial stuff (easier to work with and zigzag back and forth than the
> home made stuff).
>
> If you don't have commercial ladderline, then add about 15 (or 14 ft.) of
> your homebrew openwire to the feedline.
>
> The trick is to add an electrical 1/8 wavelength.
> I don't know the velocity factor of your home brew line, that's why I can't
> say the exact length but it will be about 14 or 15 ft, maybe even 16 ft.
>
> I'm pretty sure that will fix 40m, and probably 30m as well.
>
> MOST LIKELY, THE ONLY PROBLEM YOU ARE HAVING IS THAT YOU HAPPENED TO HIT A
> VERY UNPRACTIVAL TOTAL LENGTH OF ANTENNA PLUS FEEDLINE!
>
> I use the same antenna with the same matchbox (I have the MFJ-974B) and it
> produces a very good match on ALL bands, from 80 thru 10, but I have a
> longer feedline, whose length I have not measured. It runs exactly from
> the
> antenna to the shack, and I got lucky!
>
> 73
> Rick
>
>
>
>
>
> -----Original Message-----
> From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
> On Behalf Of tom stewart
> Sent: Sunday, February 13, 2011 7:17 PM
> To: TenTec@contesting.com
> Subject: [TenTec] Antenna follow up- asked for help in January- need more
> help.....
>
> OK,
>
> Many came to my aid when I asked for suggestions. I made some choices and
> built an antenna. I tried hard to maintain spacing and avoid metal by at
> least a foot. It did not come out well so I need help. Here are the details
> if anyone has some suggestions I would be grateful-again.
>
> 1. Purchase "Ladder Snap" spreaders to build 600 ohm feeder.
>
> 2. Purchased plenty of 14 gauge THHN wire.
>
> 3. Because of room constraints, the legs of my inverted Vee are 31 feet.
> Center is 35 feet high and the legs end at about twenty feet.
>
> 4. Legs to feeder is continuous- feeder is 45 feet from center and
> terminated by grounded shield coax through window pane(vinyl).
>
> 5. Tuner is for now an MFJ balanced- model 974-I think.
>
> 6. reactance is high on all bands. It will only tune up on 14MHZ. tuner
> arcs if I persist at 7mhz
>
> 7. readings with antenna analyzer are as follows:
>
> Readings are at the bottom of the bands beacause I operate CW only.
>
> 7.020mhz r57 x158 swr 10.0
>
> 10.110mhz r168 x 135 swr 6.0
>
> 14.020 r21 x58 swr 7.5
>
> 18.075 r20 x70 swr9.1
>
> Thanks in advance- I know it is difficult to say with this limited
> information but I am at my wits end- about 10 hours into this
>
>
> Tom N7ESE
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--
"No matter how fast you miss, you still lose."
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