Now that summer fun is over its time to get back to some serious antenna work. I decided that along with an inverted L for top band, I need a decent receiving antenna(s) to dig weak signals out of the noise on the low bands. The K9AY terminated loop looks like a good antenna to start with so I’m building that. Rather than blindly copying a known design I decided to use some new test gear I got last year to do some bench comparisons on cores I had on the bench. Very instructive, to say the least. More info here: Toroid Testing
First I framed the top and bottom of the hole to attach form sides, to keep dirt from falling in the hole – the dirt is really the form here. Bottom frame ID 47″ x 35″, top frame 40″x30″ to give pyramid shape to eliminate frost heave. Next I set and leveled the rebar, then bolstered the forms to make ready for the pour.
I calculated two yards of concrete to fill the forms with a little extra, so I made up a form to use any excess for guy wire sleepers. No guys for this tower but who knows what the future may bring?
I followed the Hygain tower recommendations for the rebar but made the block larger (two yards concrete vs 1 yard) for a safety margin. The block sits on ledge rock and should be very secure.
Hover cursor over picture bottom for manual controls.
Got the backhoe in to dig a hole for the tower base block. I’m going with a larger base block than recommended due to the soil conditions, winter frost heave considerations, and occasional high wind conditions here. My QTH is on a ridge just a few miles inland from the Penobscot Bay and the open Atlantic Ocean. Good for propagation to the East and South but subject to high winds from maritime polar air mass lows which often deepen more than forecast. Check out the rocks he had to extract. Not a project for hand shoveling!
Starting the concrete forms work. and a look at what I bought.
Here’s a short video on how the recent ice storm affected my antennas: