With May coming to an end, I am unable to find any lowfers with my new loop. So, the next project is to build a hifer antenna for 13.55~mhz. The plan is to build a simple dipole antenna from scraps around the house. Hopefully this will be sufficient to receive some hifer transmissions.
I made a 1:1 balun out of a 43 type ferrite toroid core. I wrapped 15 bifilar turns around the core. I did no calculations to design this toroid. Next I attached an 18 foot wire to each end of one of the toroid coils. I used a piece of pipe as a strain relief. I attached the other toroid coil to an F connector. I have been using 75 ohm RG6 for everything outside, because its inexpensive and I can buy it locally. The dipole should be around 75 ohms, so this works out.
Next, I used some pull ties to attach a short PVC pipe to a small tree in my yard. The antenna strain relief is attached to the other end of the pipe. I attached string to the ends of the dipole wires and attached the other ends to trees. I then used my Rig Expert AA-30 to find the resonance of the antenna. The resonance was a little low, so I shortened the antenna 6 inches at a time. After a few tries, The antenna resonated at 13555khz and had around 83 ohms. This is probably about as good as I can expect with the effor I put into it.
So, How does it work? Below is my first confirmed hifer reception. WM lowfer in Lawrenceville, IL. This is around 580 miles! There is a link to archives on my main page with more receptions.
