FM DX

FMDX as a pastime is relatively new to me. Actually, I began to DX the FM band more “seriously” during the Summer of 2016, after acquiring the SDRPlay (see this site dedicated page). In the past, I could experience occasional FMDX on the car radio for example but this was nothing compared to SDR technology where a portion of the band can be recorded for later review. Moreover, many capable SDRs can be found nowadays at a very reasonable price. Be careful however concerning the choice of a computer because recording a 10 MHz chunk takes a good amount of computing power and this has to be considered seriously in the planning of a SDR acquisition.


FM propagation compared to MW can be quite unpredictable, with the exception maybe of Tropospheric Ducting (Wikipedia) whose events are closely tied with certain weather conditions. During good “Tropo” conditions, signals can travel up to 800Km. But the most thrilling events come without contest from E-Skip (Wikipedia) propagation where signals can be heard thousands of kilometres away. The good news is that we already know that E-Skip is likely to happen in North America for instance, from mid-June up to August. The bad news now is that it can happen at any hour so unless you’re a retired person, there’s a great deal of luck in being at the right place at the right time when such conditions occurs.

As for my own experience, if I’m not taking in account scarce E-Skip events from the past years on my car radio,  I’ve been witness of one big opening so far when sitting at my listening post with my SDR running. It happened on June 13 2017 and it lasted for nearly one hour. That was a truly exciting moment. Now that you’re aware of which receiver I’ve been using, let me describe to you the antenna system I use for FM broadcast. Many years ago, I bought myself (if I recall correctly) a Canadian made Delhi 10 elements antenna for FM (above pictures). It’s a double folded dipole type. My intention at that time was nothing more than to improve the reception of Montreal stations. Now, getting more extensively in this hobby, it went back in service again.

As for the matching transformer, I wanted something that has good performance and obviously, I couldn’t trust those cheap commercial models. Therefore, I turned (again) to my friend Jürgen Bartels, who’s himself a very active FM Dxer for advice about a quality match. He kindly provided me a solution using a B 43-2402 binocular core. Each windings has two turns of enamelled wire. Choose a gauge as big as it could fit the core for a lower loss.

A view of my antenna sitting on our house rooftop tower and pointing towards New England

Now back to that E-Skip event on 06-13-2017, here’s my logs. Note that I might have been able to hear much more stations if it hasn’t been for my lack of experience with the SDRPlay. Actually, I had an issue concerning the size of the recorded files and that’s why I ended with a great number of short files to be later reviewed. This explain that relatively small number of stations logged.



Now staying true to my habits, I do have some audio clips from that day to share (Time is EDT):


92.1 WJXR MacClenny, FL (22:05)

92.3 WWKA Orlando, FL (22:04)

92.5 WYUU Safety Harbour, FL (22:04)

92.7 WBNK Pine Knoll Shores, NC (21:32)

98.9 WBAM Montgomery, AL vs CHIK, Quebec City (local) (21:36)

99.3 WLRQ Cocoa, FL (22:16)

101.5 WSOL Brunswick, GA (21:21)

101.7 WAVF Hanahan, SC (21:20)

103.1 WIRK Indiantown, FL (22:00)





This page is a work-and-progress and hopefully, I could add some more content in the seasons to come.

Page created on Sept 2017