Sunday, 21 January 2018

160M vertical antenna project

160 Metre Helically Wound ¼ wave vertical antenna

Following an article I found online (will post) I started contemplating a 160 metre vertical.  I live on a small lot, close to some lousy power lines that often are noisey.  My horizontal antennas are useless when the "insulators start a humming"  and verticals seem to have a much better S/N ratio in these conditions.  As the propagation is so poor these days I often find I am getting pushed down onto 80 and 160m.  With no proper antenna for 160 (several other failed projects, mostly loops around the whole house on the roof) I thought I would try a vertical.  It worked, hence worth telling others about.

I found a 42 foot cedar pole,  3.5" at the butt and ½ " at the top.  It was light enough to put on my shoulder and hike out of the bush.  I dragged it on the snowy streets the last stretch to my QTH.  
 I trimmed it off a bit top and bottom, then made sure it was dry before coating with stain.
 500 foot spool of stranded #20 wire
 Put about 300' or a bit more on the pole.  Finished height 38' .

After a chilling antenna day, assisted by Bruce Lauer, VE3QX, (appropriately plied with espresso and waffle breakfast) the 160m vertical was raised.  

We fashioned a big "claw" out of 2x4 lumber to attache mid point to roof.  It will be tidied up and stained in warmer times.  It was -18 C when we put it up.  

TUNING:  Wow, did I ever put too much wire on the antenna......about double.  After a number of minor attempts at jumping a few winds, I ended up on the roof.  I had to remove the lower 17 feet of coil!!

SGC autotuner at base

Goofy claw visible.  As is the equally goofy tin capacitive hat.  

Without the tuner in the circuit, and with two radials strewn about the back and side yard, here is the match.  

It has proven to be very immune to local power line noise and really a stellar antenna for 160m.  I have worked a handful of station on SSB, and a huge number on FT8.  It is a great antenna for poor propagation days.  

PAL 500 Power Amplifier