Great for VLF/MF receiving

I am a happy user of the Alpha S9v43 — but more for radio research than ham radio, until the opening of 2200 meters and 630 meters — this is the only antenna with which I have logged 2200 m band WSPR signals; on 630 m, some WSPR signals come booming in (more or less). This antenna has been up for a couple of years. The California Historical Radio Society sponsors as one of its programs, the VLF Interest Group. We’re looking at 11 KHz to 137+ KHz. The main receiver here at K6VK is a WinRadio G33 SDR.

We all make loops, of course but at these frequencies the loops are full of the magnetic components of 60 cycle harmonics. The S9v43 is immune to these pests, and K6VK is surrounded by power lines. It is the quietest VLF antenna I have.

With it I have logged the Russian Alpha stations (e.g., 11.9 KHz), France, Germany, Japan, Russian Military World-wide (22 KHz +-), and the high-power US Navy stations (25 KHz +-) all over the world. It is just an e-field probe at these frequencies, but the best antenna, nonetheless. It connects to the SDR by solid copper conductor IBM RG-11 coax. There is very little vertically polarized noise at these low frequencies. Almost all the transmitters are vertically polarized. I’d like to put up an array of S9v43s. Even a couple could handle some kind of light wire capacity hat for transmitting, although I am not there yet. K6VK does enjoy about hundred square meters of ground screen and a world of ground radials and five ground rods. And for safety, it’s a good idea to make installation (and repair) a two-man project. When the sunspots come back, I look forward to trying this antenna out on HF, where it certainly receives pretty well.