Marine Vertical Installation with Radials

img_2150Having installed my old Shakespeare Marine vertical a while ago as a ground-mounted vertical, today was radial laying day. I’ve read that laying your radials out in the spring, across the lawn, means that the grass will grow up and gradually bury them under the grass thatch. I hope so!

Since I’m only having a test, I laid out 16 radials across a 180 degree arc. I can’t lay any radials in the other arc since the house is in the way.

img_2143I used PVC coated 7 strand D10 military wire which has seven small strands; four steel and three copper. They are the maximum length that fits in my small yard here, between about 6m and 12m in length. Near the feedpoint, I drilled a large hole in a piece of redundant 1 inch wood and fed all the radials through this and under some gravel to the ATU. I did the same at each end of every radial; a small hole which allowed the D10 to snake through before hammering them into the ground under tension. 

img_2142The bundle of radials connects to an SG230 ATU which I screwed to the wall right next to the vertical and used a small 12V DC gell battery to power it.

Some days, you get lucky and today was one of them. I found a in my junk box, a 15m section of low-loss coax already with PL259 connectors on. I also discovered a neat 1 inch hole that I had drilled though previously (and subsequently gooped up with mastik) very close to the ideal entry point to my “bunker”. Cleaning the goop out was fairly straight forward and the coax length was so perfect, I couldn’t have cut it any cleaner. Lucky day indeed.

img_2145Results: As predicted, local (zero to 500 miles) signals on 40m are rubbish but from 14 MHz upwards it really has some legs. I can easily copy signals across the Atlantic and the SG230 tunes every band and (from 160m to 10m) with ease.

(2 months later) I laid 9 more radials and removed the SG230, multi-banding this antenna for 40m and 15m instead. See here: Multi-banding a monoband 40m vertical

What a good day for having fun with RF.

73. Callum.

Photo gallery follows: