After building John, K6MM’s antenna and having great luck with it, I decided to experiment further. You can find the initial construction here on my website.
You can find John’s plans here on his website.
I had great luck with this antenna until a storm hit. A brench fell off a redwood tree on my property and snapped some guy wires as well as did this below to the capacitance hat.
So I decided to replace it with something pre-manufactured. I went o DX engineering website and found this capacitance hat.
Model: DX Engineering CW Optimizer Capacity Hat Kits DXE-7580-THK, ~ $75
It was intended for one of their antennas but “same difference” as they say. I wanted to makes sure this time it is not going anywhere! I used two hose clamps, the wire was stripped back quite a bit and treated with conductive grease. Keeps rust out and improved conductivity. I used Gorilla tape below to improve the grip.
Here is a slightly different view. You can tell I bent the radials to give a little better spacing. No math behind it just wanted to distribute it evenly….so I guess only some basic geometry!
This was then wrapped with Coax Seal, then watertight gorilla tape and for good measure a zip tie. I will let you know after a few seasons how this holds up!
One other thing I experimented with was trying to trick the antenna into thinking it has longer radials then it really does. I do not have enough land to run the required, or rather recommended length radials for 160m. My thinking is just do what I can and go with it. This coil below (PVC Pipe with a few winds of the same spacing as the antenna) connected to the ground side may help. I take this on and off and frankly not sure if it does any good but at times makes me feel better.
Here is the new “final antenna” (for now) with the new capacitance hat. As we know A capacity hat is a way to make an antenna that is not full size seem electrically longer. This new hat does seem to have more elements but most importantly is less likely to get banged up next storm.
One thing to note: I did have to retune the antenna (shorten the length of cable used actually) since adding this new capacitance hat. I tuned this for 1.840 FT8 frequency but now can move about the CW segment and a bit above FT8 calling frequency without going past 1:2 which is amazing.
Since this photo, I have replaced the guy wires with Mastrant rope and also started experimenting in modification for the 630m and 2200m bands.
Be on the lookout for more information on that soon!
If you find something incorrect, have an update, or if there is something you would like to see added to the site, drop me a line here. I like to keep things as up-to-date and as accurate as possible. Thank you! – Lucas / W6AER
