Topband: 160m Vertical matching Help

[MR TREVOR DUNNE]

Thanks everyone for the replies, I'm new to all this so you may go easy on me, I don't understand this R+JX stuff so I need a dummies guide if possible,

I have the vertical section at the top of the coil and I connect the feed line to it where I can get the lowest SWR at 1.825mhz,

Does the amount of coil left under the tap matter I didn't know it would as it's going to ground,

Ideally I don't want to drop the loading wires as they are not easy to get to but I can if I need to,

Thanks
Trevor



----- Original Message -----
From: "Richard (Rick) Karlquist" <richard at karlquist.com>
To: "MR TREVOR DUNNE" <ei2glb at eircom.net>, "topband List" <topband at contesting.com>
Sent: Wednesday, 1 November, 2017 17:25:25
Subject: Re: Topband: 160m Vertical matching Help

You need +j34 ohms in parallel with your coax coming in.
This is about 3 microhenries.  This would be around 6
turns on your coil if the turns are spaced a wire
diameter.  IOW, tap the coax 6 turns from the grounded end.
Then tap the antenna to whatever tunes to 1.83 MHz.

Rick N6RK

On 11/1/2017 9:54 AM, MR TREVOR DUNNE wrote:
> 
> Hi All
> 
> 
> 
> I finally got the vertical up and running, problem I have now is I can't find a low SWR on the coil, the best I can get is about 2.8:1 no matter where I tap the coil that's the best SWR, I can move that point up and down the band by moving the tap but the SWR stays the same,
> 
> My current set up is about 55ft vertical I have 2 loading wires in a T shape, wires are 50ft either side of the vertical and the are pretty level and in line,
> 
> I have 38 radials averaging about 45-60ft long, I will add more when time allows but don't the make the SWR worse ??
> 
> With no coil I get resonance at 2.12mhz with R=16 X=2 on my MFJ269,
> 
> The coil is 25ft of 5mm copper brake pipe in a 4" diameter, the coil is attached to base of the vertical and the other end is grounded,
> 
> Any pointers on what I can do to get a better match,
> 
> Thanks
> Trevor
> EI2GLB
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