Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who writes:
Dear Thomas and Friends of SWLing Post,
I am Giuseppe Morlè from Formia, Central Italy, on the Tyrrhenian Sea.
This time, I want to share a very simple antenna setup for listening to and attempting extreme DX on Medium Waves.
I first saw this antenna in several videos, and many DXers have used it during various expeditions.
For my setup, I used a 15-meter-long wire. At around 11 meters, I formed a small coil with 8 turns, then continued the wire for another 3 meters.
I began with some tests on my balcony by laying the wire flat along the ground for its entire length. I used my small Sony SRF-37V as a receiver. By placing the receiver within the coil of turns, I immediately noticed a significant difference compared to the built-in ferrite antenna.
In the early afternoon, I tuned into a Chinese language broadcast on 1377 kHz. You can watch a video of this experiment on my YouTube channel:
Encouraged by the excellent results, I decided to head to the tourist port of Caposele di Formia the next day in the early afternoon. I set up on the pier overlooking the sea. This time, I laid the wire in an eastward direction — towards the night, where the sun had already set, while it was still high for another two hours on my side.
Once again, I achieved amazing results.
I was able to hear the same Chinese station on 1377 kHz, but this time with much clearer audio than from my balcony, where electrical noise interfered. By the sea, the signal was clean and strong.
After a while, I tuned into VOA broadcasts from Thailand on 1575 and 1395 kHz, both with surprisingly good audio quality. You can see this second experiment here:
Sometimes, all it takes is a bit of wire and a small coil to create an excellent, ground-level antenna — in this case, oriented eastward.
I also tried using my loop cassette and a Tecsun PL-660 but couldn’t hear anything. Yet the little Sony SRF-37V proved itself to be a true “DX killer” on AM — truly impressive.
I even caught a segment of the VOA program “World Today,” discussing the Chinese economy and Southeast Asia.
As the sun set, the DX signals faded, making way for closer European and Asian broadcasters.
I will definitely return with a longer wire to see if this surprising setup can be improved even more.
A warm greeting to all the Friends who follow SWLing Post and to you, Dear Thomas.
73, Giuseppe IZ0GZW
I think the Sony SRF-37V is the best pocket radio made ever. I’ve had mine for at least 25 years, and it is still working. And using that receiver, putting it in the vicinity of my Tecsun AN-200 tuned MW antenna, has produced stunning results, even with all the electrical noise at home.
Unfortunately they are not produced any more, and I see they go for up to US$ 300 on Ebay. If I remember right, I paid around US$ 20 for mine.
And to OENE: You don’t need any schematic for using any MW receiver with built in ferrite antenna with an aerial such as the one Guiseppe describes. Usually it is enough just placing it near the end of the antenna, or you can do as Guiseppe, winding the end of the antenna a few times around the receiver. Works well for any portable AM receiver. Just try it!
And Guiseppe, thank you for sharing your videos with us! I don’t understand Italian, but the way you demonstrate what you do in your videos makes me understand anyway.
Good Luck!
Egil – LA2PJ
Thanks Egil,
in fact the Sony srf 37V is truly a “war machine” for extreme DX…
I also used my cassette loops and the AN100 but the coil wire is truly an excellent antenna for this small receiver…
it manages to cancel the noise with a galvanic isolator effect and has a performance that far exceeds the various tuned loops…
73 and happy listening.
Wow! . . . just Wow!
Cheers, Jock
Thank’s Jock…
good listening.
73. Giuseppe.
Very nice experiment ! Can you make a schematic drawing because it is not clear to me where the receiver end of the antenne is connected or is it not connected at all ? Answer would be very appreciated.
The coil wire antenna is NOT connected anywhere…
the longest part of the wire must be pointed in the direction you want to listen to, then there is a 10-turn coil and then the shorter part continues that could be grounded as ground…
the longer the wire is much better…
in my video the wire is 15 meters long in total, there are 11 meters of the longest part, the wound coil and another 3 meters for the rest…
the antenna takes the signal from the long wire and passing through the induction coil brings the signal to the ferrite of the receiver…
the other part of the wire must be grounded…
73. Giuseppe iz0gzw.