a drawing guys would help
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On November 1, 2017 12:28:35 PM MR TREVOR DUNNE <ei2glb@eircom.net> wrote:
> 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@karlquist.com>
> To: "MR TREVOR DUNNE" <ei2glb@eircom.net>, "topband List"
> <topband@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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>>
>>
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