Category Archives: Antennas

Frans add a Decca manual antenna tuner to his urban listening post

Many thanks to SWLing Post contributor, Frans Goddijn, who writes:

Hi Thomas:

I bought a vintage antenna tuner, one that does not need a power source, very basic just a box with some beautiful coils and nice big variable capacitors and it works for the big magnetic loop antenna here.

I have four GRAHN loop antennas which each have their box with dials to fine tune the signal but the big loop didn’t have that yet.

The tuner works well, filters out some noise but I must say the iCOM radio also managed to select good signal from the loop with its own tuner system and the DSP noise filter at the speaker end of the system further clears up the voice sounds.

Video:

Best regards,

Frans

The internals of manual antenna tuners are simply hypnotizing, aren’t they? You’ve a beautifully-built tuner there that is functional and will outlive us all!

Thank you for sharing!

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Saturday morning fun: “fat” MW DXing with the MFJ-1886

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By Jock Elliott, KB2GOM

It was a reader, Mario Filippi, who set me on this path. He posted a comment that said, in part: “An interesting place to DX would be the segment between 1500 – 1590 kc’s where there are a number of news stations, one being federal news on 1500.”

Huh, I thought, federal news? I wonder if I can hear that. So I hooked up the MFJ 1886 Receive Loop Antenna to my Grundig Satellit 800 receiver and tuned to 1500. With the 800’s whip antenna, I heard mostly static; switching to the 50-foot indoor room loop, pretty much the same; same thing with the 1886 with the amplifier turned off. But turn the 1886’s amplifier on, and it was like getting slammed against the wall by the schoolyard bully: LISTEN TO ME! A big, fat, S9 signal, sounding like WGY 810 just a few miles from me. Wow, I thought, this loop can really pull out a signal.

A little research revealed, as nearly as I can tell, that Federal News 1500 is in Washington, DC, over 300 miles from me. Over the next few days I would occasionally check on Federal News 1500 using the 1886 loop, and typically it was loud and clear here in Troy, NY.

Hidden behind a curtain, the 3-foot aluminum loop of the MFJ 1886 works well for MW DXing.

Early this morning, Jan. 28, 2023, a thought crept into my brain: how many big, fat, MW signals could I detect with the combo of the Satellite 800 and the MFJ 1886 loop antenna? (Bear in mind that my 1886 rests flat against a window and is NOT rotatable in its current configuration.) Here’s the log, with station IDs when I could get them.

Time Frequency Station

1100Z 1520 WWKB Buffalo

1102Z 1530 Milwaukee? Sports, Australian open

1106Z 1540 CHIN Toronto, old time radio programs

1112Z 1560 religious music

1115Z 1660 orchestral music, Strauss waltzes

1118Z 540 middle eastern music

1121Z 660 WFAN, NYC

1124Z 700 WLW, Cincinnati

1127Z 710 WOR, the Voice of New York

1129Z 730 French language, Canada mentioned

1132Z 750 WSB, Atlanta

1134Z 770 WABC, NYC

1135Z 790 ortho doctor show

1138Z 860 French language, Canada mentioned

1140Z 880 WCBS, NYC

1142Z 1010 WINS, NYC

1144Z 1020 Talk

1146Z 1030 WBZ, Boston

1148Z 1050 WEPN, ESPN radio, New York

1149Z 1060 KYW, Philadelphia, PA

1153Z 1090 WBAL, Baltimore

1154Z 1110 WBT Charlotte, NC

Bottom line: it was immense fun, tuning around for “fat” MW stations in the early AM. Periodically I checked the other antennas as I traversed the band, but universally the MFJ 1886 was better at pulling them in.

Fat station DX? You bet! Try it; you’ll like it!

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PDF: Analysis and Design of FSL Antennas

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Many thanks to SWLing Post contributor, Zoltan Azary, who has written an extensive theoretical analysis of ferrite sleeve loop antennas. This article has a very academic flavor and for those who are interested in antenna design, he welcomes your comments!

Click here to download the 14 page PDF, “Analysis and Design of FSL Antennas: Open Source Hardware Engineering” by Zoltan Azary.

Thank you for sharing this work with us, Zoltan!

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Born in the ER: Andrew’s portable SULA antenna

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Many thanks to SWLing Post contributor, Andrew (VK2ZRK), who writes:

Just thought I would share some pics of my SULA build which I constructed in the Emergency department’s antenna building section in between catastrophies here in Australia.

I built it out of 8mm fibreglass tube from a kite supply, 8mm kite nocks, 13mm equal cross irrigation fitting and lots of double wall glue lined heat shrink. The 8mm tube with a short bit of heat shrink is a slip fit into the id of the 13mm equal cross which I secured with more heat shrink.

I then cut the frame to length allowing for the length of the kite nocks. I secured the kite nocks with more heat shrink. I then soldered the resister to 2 lengths of Davis RF 12g antenna wire and fed this through the kite nocks terminating it at the nooelec balun on the opposite side to the resistor.

I think it worked out well. It is very light. I built it to use with my SDRPlay RSPdx.

Thank you to everyone involved in the design process and for providing it to the swling.com community.

Cheers
Andrew VK2ZRK

In all the years I’ve been hosting the SWLing Post, I can safely say that we’ve never featured an antenna constructed in an Emergency Department of a hospital. Thank you, Andrew!

The feedback from the SULA antenna build has been phenomenal. The three-part series detailing the SULA antenna from concept to build was the most popular of 2022 on the SWLing Post.

Thank you for sharing the photos of your antenna. What a professional job, Andrew!

Readers, if you’d like to learn more about the SULA antenna, check out this three-part series–a collaboration between the amazing Grayhat and 13dka.

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A little daytime Medium Wave DXing . . .

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By Jock Elliott, KB2GOM

Let’s get one thing clear from the start: it’s all Ken Reitz’s fault. When the search for the guilty begins, the finger should point squarely at Mr. Reitz.

Who is Ken Reitz? He is the Managing Editor and Publisher of The Spectrum Monitor.

The Spectrum Monitor is a radio hobbyist magazine available only in PDF format and can be read on any device capable of opening a PDF file. It covers virtually aspect of the radio hobby, and you can find it here: https://www.thespectrummonitor.com/ I am a subscriber, and I can heartily recommend it without reservation.

So what is it that Mr. Reitz did that set me off? Short answer: he wrote a really good article entitled “AM DX Antennas: Long Wires and Loops Big and Small.” In it, he mentioned that he could hear, from his location in Virginia, WCBS on 880 in New York City, some 300 miles away. He also mentioned that he could hear, during daylight hours, WGY in Schenectady, NY, about 400 miles distant.

WGY is a local station for me in Troy, NY, but I wondered: Could I hear WCBS in New York City? That’s nearly 150 miles from me. Hmmm.

So I started firing up various radios and radio/antenna combinations on 880 kHz. I tried my Icom IC706 MkIIIG ham transceiver, hooked to the 45-foot indoor end-fed antenna. Nothing heard.

Next, my Grundig Satellit 800 connected to its 4-foot whip antenna. I could hear WCBS barely, but with a horrible buzzing noise. Switching the Satellit 800 to the horizontal room loop antenna I could hear WCBS better, but the noise was really, really nasty.

One way to preserve domestic tranquility is to hide the MFJ Loop behind a curtain!

Then I connected the MFJ 1886 Receive Loop Antenna. Tah-dah! I could hear WCBS just fine, with some noise in the background, but “armchair copy.” The MFJ loop made a huge difference in the quality and strength of the signal. I also tried the MFJ loop with another radio I have under test (its identity to be revealed in the future) and found, while I couldn’t hear WCBS at all with the radio’s internal antenna, the 1886 made an enormous difference, pulling out a fully copyable signal with noise in the background.

Finally, I tried a couple of my portables. My Tecsun 880 could hear WCBS, but the noise level was high enough to be annoying. Finally, I tried my CCrane Skywave SSB. The Skywave did a better job of pulling the signal out of the noise. I got the same result with the CCrane Skywave SSB2. Both Skywaves were using their internal ferrite antennas. Impressive.

Bottom line, for this very small foray into daytime medium wave DXing, the MFJ-1886 Receive Loop Antenna was a powerful and useful tool, one I can easily recommend. Second, when it comes to portables, the CCrane Skywave SSB (either model) continues to show that it is “The Little Radio That Could.”

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Video: Giuseppe’s “Cassette Loop” on the shortwaves with induction

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Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who writes:

Dear Thomas and Friends of the SWLing Post,

I’m Giuseppe Morlè from central Italy, Formia on the Tyrrhenian Sea…

My Cassette Loop experiment this time shows how induction takes place on short waves after medium waves.

I used a smaller box as the primary antenna which, however, is pushed by the secondary one due to the induction effect generated between the two windings brought closer together.

This way, the larger loop “captures” more of the signal and sends it to the smaller cassette…

I really like working on induction… I hope you like it: