a drawing guys would help Sent with AquaMail for Android http://www.aqua-mail.com
On November 1, 2017 12:28:35 PM MR TREVOR DUNNE <ei2...@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" <rich...@karlquist.com> > To: "MR TREVOR DUNNE" <ei2...@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 >> _________________ >> Topband Reflector Archives - http://www.contesting.com/_topband >> >> > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband