Monday, November 18, 2019

Late fall antenna tweaking...

Wasn't real happy with a few of my antennas so I decided to attempt to improve the match. 

20m 1/4 Vert ...just behind the house. 

Took some length off the Vertical element SWR is now

Freq        VSWR
14.0          1:1
14.5          1:1
14.1          1:1
14.15        1:1
14.2          1:2
14.25        1.3
14.3          1.4

Super happy with that ,  worked an RU this morning CW.  Tried to work a guy in Bulgaria but wasn't successful switched to the 160m vert at the top of the hill and was successful. 

80m inverted L ( 1/4 vert ) 

Took a wee bit off this antenna too but its not nearly as broadband as the 20m antenna.  Suspect a tweak of the radials might help that out but its not happening until the snow goes which may be April.

Freq      VSWR
3.45        1.9:1
3.5          1.45:1
3.55        1.4:1
3.6          1.5:1
3.65        1.8:1
3.7          2.2:1

So yeah,  I am mostly CW and FT8 on 80m so its great there however go up and not so much.   Think I may try a low dipole cut to 3750 for SSB. 

160m inverted L ( 1/4 vert )

Same this goes took a foot off the vert radiator

Freq        VSWR
1.7            2.1 :1
1.75          1.4:1
1.8            1.4:1
1.85          1.7:1
1.9            2.1:1

Again great for CW and FT8 but not so much for SSB.   This is my " magic " antenna that loads up on 40,  30,  20,  17, 15,  12, 10, 6 meters with just the antenna tuner in the radio!     I have had success on 6m meteor scatter running 100 watts into this antenna.   A while back ( in the blog somewhere ) I compared the 20m 1/4 behind the house with the 160m L up the hill and the big guy performed better! 


Here is how the 160m loads ...no antenna tuner!

Freq   VSWR
80m NO WAY ,  does not work
40m    3.6:1
30m    3:1:1
20m    2:1:1
17m    2.1:1
15m    1.5:1
12m    1.6:1
10m ( 28 MHz ) 1.4:1
10m ( 29 MHz ) 2.1:1
6m    (50 MHz ) 1.5:1
6m    (51 MHZ ) 1.3:1
6m    ( 52 MHz ) 2.1:1

From 50.6 to 50.9 MHz its a dead flat 1:1 VSWR...go figure

I use the 160 antenna when work FT8 remotely ,   no antenna switching required and I can flip around between bands super easy.