Topband: 160 meter band Antenna.

[Rune Øye]

Hello All

 

To day i tried to tune my antenna for 160 etc.

Some info here about how it is built.

 

About 17 meter vertical, 3 top hat mounted @ 15 meter.

Each hat is14.5 meter, sloping 45 deg.

 

Now, 24 radials on ground 110 foot in length.

 

Have made an L-network  (signal in series with coil, and variable C after coil to ground)

The coil is made on 65-70 mm fibreglass tube and is totally 50 uH. (Close to 1 uH / turn)

Have tap so I can shorten turns etc.

My capacitor have value from about 90pF to about 350 pf

 

On 80 meter band I am using about 24 uH and something between 150-250 pF.

(Did not measure C) swr is good.

 

When I shorten my coil the antenna is resonant around 1.830 Mhz (strange with 15+14.5 meter) the swr value is something around 3+  from my MFJ analyser I measure around

12-15 ohm on meter.

 

GENTS, and antenna gurus, I am not nay expert on this.

How should I match my antenna for 160, do I need an step up balun, or change the 

position on my capacitor to other side of coil.

 

On 40 meter band I used something like 12-14 turn, but did not find any "dip"

Wondering if minimum value of my capacitor is to high here.

 

This antenna is mounted on my remote qth for remote operating on 160, base of antenna is about 10-12 meter from sea on high tide water, so hope this will give me some more

"HELP" on 160 comparing to my home "rock" QTH.

 

 

Hope there is someone out there that understands this, and can give me some help.

 

73 de Rune LA7THA from remote qth.

Rune Egil Øye
New mail address : la7tha at tussa.com