Category Archives: Antennas

Radio Waves: Exploring a Super Tower, Former BBC HQ, OTA Radio When all Fails, and Saving Historic Radio

Radio Waves: Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors Dennis Dura, Rich Cuff, Ron Chester, and David Iurescia for the following tips:

Exploring a 1 Million Watt Broadcast Tower (Radio World)

The father and son team of Joe and Jeff Geerling have teamed up on radio-related projects before.

Joe is a broadcast engineer, working into his fifth decade in the St. Louis market. He was market chief for CBS Radio for 20 years and today is the director of engineering for Covenant Network.

His son Jeff has spent nearly 15 years as a software architect and developer. He founded Midwestern Mac LLC and is active in many open-source software communities. Jeff recalls that one of his first web programming projects in the late 1990s was to construct an interface to display the current song on 98.1 KYKY(FM)’s initial website for his dad.

Last February, Joe appeared on a video on Jeff’s YouTube channel to install a Raspberry Pi IP KVM in a Covenant Network studio. That collaboration went so well that commenters on Jeff’s videos began clamoring for more appearances by the senior Geerling.

Over a family vacation, Joe and Jeff came to the realization that the iconic Crestwood Master Tower in Shrewsbury, Mo. — nicknamed by its original engineering community as “the Supertower” — would make for a perfect showcase for a new Geerling Engineering YouTube channel.

Given Joe’s expertise with the site, the idea for a video was a natural. In fact they ended up making two. [Continue reading…]

Amancio Ortega is testing the purchase of a former BBC headquarters in London for almost 90 million (West Observer)

The investment activity of Amancio Ortega in the United Kingdom does not stop. Pontegadea, the group that manages the equity investments of the founder of Inditex (Zara, Massimo Dutti, Bershka…) and the richest man in Spain, is negotiating the purchase of a new office building in London, as revealed on Wednesday by the specialized website CoStar News. This, citing market sources, indicates that the operation would be around 80 million pounds (89.7 million euros, at current exchange rates). The building, originally a printing press built in the twenties, is close to the BBC headquarters and, in fact, for years served as offices for the commercial division of British public broadcasting.

The property, renovated in 2015 by the construction company Kier and the firm Brimelow McSweeney Architects, currently houses a business of coworking (flexible office rental). Of the more than 3,000 meters built, 2,100 are available for rent, according to the building’s commercial brochure. Some websites advertise their tables for a price that exceeds 840 euros per table per month. It offers, in addition to parking for bicycles or changing rooms, a kitchen, private offices, meeting rooms or terraces on the upper floor (the fifth) and on the roof. To this we must add a privileged location in the center of the British capital, in the Fitzrovia neighborhood. The building is close to Soho, the British Museum and Regent’s Park. [Continue reading…]

What’s Going To Happen To Legacy Broadcast Bands When The Lights Go Out? (Hackaday)

Our smartphones have become our constant companions over the last decade, and it’s often said that they have been such a success because they’ve absorbed the features of so many of the other devices we used to carry. PDA? Check. Pager? Check. Flashlight? Check. Camera? Check. MP3 player? Of course, and the list goes on. But alongside all that portable tech there’s a wider effect on less portable technology, and it’s one that even has a social aspect to it as well. In simple terms, there’s a generational divide that the smartphone has brought into focus, between older people who consume media in ways born in the analogue age, and younger people for whom their media experience is customized and definitely non-linear. Continue reading →

The CCrane Skywave SSB 2 and long wire antennas

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By Jock Elliott, KB2GOM

Frequently when people write about attaching a long wire to a portable shortwave receiver, readers will comment that you need to worry about desensitizing or overloading the receiver or ever harming the front end of the receiver. Clearly that can be a concern.

But recently I noticed something on the CCrane website in the FAQ section that shows clearly that CCrane has thought about and dealt with this consideration:

Q: When using the 2-wire adapter and wire attached, why am I not noticing any improvement on shortwave?

A: To see any difference using the 2-wire adapter you will need to have a wire that is more than 30 feet long (we recommend 60-100’) with a good ground wire. Insulated wire will last longer and should be stranded so it is more flexible. If you do not have a good ground, you are actually inputting noise. If you look at the 2-wire adapter (included) you will see an antenna icon and a ground (G) marking. You need to connect them properly when using an external antenna. When a plug is inserted into the antenna jack of the radio the internal rod antenna is disconnected. (See page 30 of the Instruction manual.)

If you check out my review of the CCrane Skywave SSB 2 you will read that I heard a noticeable improvement when connecting the SSB 2 to a 45-foot end fed wire.

Note, though, that if you plan to attach a wire to the SSB 2’s whip antenna, use the 23-foot reel antenna that comes with the radio.

Loop-On-Ground Antenna Part 3: Tom’s low-noise, low-profile, portable antenna evolves

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Loop on Ground Antenna Part 3

(using multiconductor wire)

by TomL

It dawned on me recently, perhaps due to sloppy thinking or unintended distractions, that I never wrote about my modified Loop on Ground (LoG) receive antenna that I use at parks and such. For over a year now, I have been using 3-conductor rotor wire bought cheap at the local hardware store and have wired the conductors in series. Grayhat (Andrew) was the inspiration when he decided to create a folded dipole along the side of his house.

The usual construction of a LoG antenna for shortwave is a single wire of about 60 feet in circumference in order to not go above one wavelength for 20 meter band usage. If you recall, going above one wavelength will start creating weird lobes in the reception pattern. See – Loop-On-Ground Antenna Part 2.

However, I did not like this 19 foot diameter wire on the ground in public parks just waiting to be tripped over. Like, the time when a horse got loose from its owners and almost tripped over my 60 foot wire. I don’t think I would have liked the resulting lawsuit!

So out of fearful necessity I took some leftover RCA 3-conductor rotor wire, about 29 feet of it, and wired a loop with the conductors in series. This gives about 81 feet of total conductive length. But since it is folded onto itself, there is an undetermined loss of resonant length. Callum (M0MCX) of DXCommander fame has experimented and found folded dipoles need three times more length in the folded section to reach resonance, so my loop is probably around 69 feet (electrically). See – Fold the end of a Dipole Back – What’s Happening?.

In the picture below, the black wire with Ring Terminal at the bottom goes all the way around to the other side, soldered to the green wire, which goes around and is soldered to the red wire, which goes around to the Ring Terminal at the top, plus tie-wraps to hold the wires together.

The next picture is how the Wellbrook Medium Aperture preamplifier is connected to the loop with BNC cable that goes to the 12V power injector. I have had this Wellbrook unit for maybe 6+years with no signs of problems. WARNING – do NOT use the Wellbrook preamplifier in the presence of high powered RF energy like your Amateur Radio antenna pumped with 1000 watts from a linear amplifier; the Wellbrook premap might just overload and get damaged! I did use this loop and preamplifier at last year’s 2022 ARRL Field Day and was able to get away with it because we were only using 100 watts per station. Listening to the 9pm 3916-net trivia group was fun but I still needed to keep it away from the transmitting antennas. Continue reading →

Jack remembers the Eavesdropper Antenna

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Many thanks to SWLing Post contributor, Jack Dully, who shares a link to this Eavesdropper antenna on eBay and writes:

When I had my roof top antennas, with the original building owner, I put up the Eavesdropper. There were 2 versions: this one with the twin lead-in and the second with a coax lead-in connection. I had both. One strung E&W and the 2nd N&S with a MFJ ant. switch. Both were up for about 7 years with a Zap Trapper surge protector and good cold water ground. They were pretty rugged withstanding blizzards, hurricanes and summer thunderstorms.

Back then, a company called Antenna Supermarket sold them for about 45 bucks a piece. Both worked great for me and they were only about 45′ long center fed From Yonkers, N.Y. I could pull in Madrid and Australia and New Zealand very clearly on my Eton E-1 XM. So I thought some readers might be interested in buying an eavesdropper on eBay, it works well. Take care and enjoy !

Thank you for sharing that, Jack!

I remember seeing the Eavesdropper advertised back in the day. I still believe it must have one of the best antenna names ever! The product image brings back memories of browsing radio catalogs!

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

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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!

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!

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!