Tag Archives: Wire Antenna

Shortwave antenna options for apartments, flats and condos

A balcony is your friend, if you have one. Otherwise, we need to use other antenna tactics!

Many thanks to SWLing Post contributor, Tim, who writes:

I am a regular subscriber here, but until now have not formally commented. I’ve been an avid SWL since 1977.

I am intrigued by your in-depth article on understanding and setting up SDR’s. But, what about an antenna? How well will these radios work for someone who is an apartment dweller?

I live here in South Florida and am unable to erect anything outdoors. I do get pretty good reception on my Grundig Satellit 800 and Tecsun PL-880. For these, I use either an indoor slinky antenna I bought on E-Bay; or an active indoor tunable loop antenna. This is one of the models past reviewed by you. It is Australian made, and covers 6-18 MHz. Please comment if you can on antenna usage.

Thank You very much!

First of all, I’m glad you enjoy the SWLing Post, Tim!

Great question: no doubt you understand that the antenna is the most important part of your radio equation!

It sounds like you’re currently using a slinky antenna and a portable PK Loop HF antenna.

The PK Loop

You’re on the right track with a PK Loop if you live in an apartment and have no way of putting an antenna outdoors. Being a small magnetic loop antenna, the PK Loop should help mitigate a bit of the noise in your apartment building.

What I love about the PK Loop is it’s small enough that you can re-position and rotate it to tweak noise rejection and find the quietest spot in your listening room. When I travel by car and even by air, the PK Loop is a welcome companion.

Before we talk about investing in a better indoor antenna, let’s make sure we cover a more affordable option first…

External wire antennas

If you have operable windows in your apartment, even fishing a thin-gauged wire out of your window–allowing it to simply hang along the outside of the building–could improve your reception significantly. Of course, if there’s a source of noise outside of your apartment it might only make things worse, but this is at least an inexpensive experiment and the results might impress you.

I actually tested this theory once and published the following results in a previous post about the PK Loop:

I had a fantastic opportunity to evaluate how well the PK Loop would perform in a typical hotel room. My buddies Eric (WD8RIF), Miles (KD8KNC) and I stayed overnight in a hotel on Wright-Patterson Air Force Base during our mini National Parks On The Air DXpedition.

The hotel room was indeed dense with RFI.

We hooked my Electraft KX2 to both the PK Loop and to a simple random wire antenna.

Without a doubt, the PK Loop was much better at mitigating radio noise than the wire antenna we hung on the inside of the hotel window.

Unlike most modern hotels, however, this one actually had operable windows, so we tossed the random wire out the window and made another comparison. In this case, the external wire antenna consistently outperformed the PK Loop, no doubt because it had the advantage of being outside the radio noise cloud within the hotel’s walls. It goes to show that outdoor antennas–even if simply hanging from a room window–will almost always outperform comparable indoor antennas.

So, if you have a way to dangle a wire out one of your window, give this a try.

How long should the wire be? I suppose it depends on how much vertical space you have below your window. For starters, I’d try to suspend at least eight feet of wire outside. If I had the vertical space, I’d try as much as 31 feet.

Important: First you must check to make sure your wire couldn’t possibly touch electrical lines. Never lower a wire outdoors if the wind could blow it into an electric service entry point, power line or any other type of line or cable. You should do a thorough inspection of the site first.

With that said, keep in mind: Stealth is key!

Photo by jay blacks on Unsplash

Can you spot the wire antenna in this photo? Of course not.

Use a thin wire with a black or dark jacket/insulation. Only lower it when using it–don’t leave it out all day long. Check to make sure your antenna isn’t going to interfere with your neighbors below (like landing in their outdoor grill or flower pots!). One strong complaint from neighbors could shut down your operation permanently.

Now back to loops…

If you don’t have operable windows or a way to deploy a wire antenna outside–or you’ve tried a wire antenna and results were unsatisfactory–then you will be forced to stick with indoor antennas which almost always leads you down the path of larger amplified wideband magnetic loop antennas.

This is a topic I covered extensively earlier this year.

Please read the post: Indoor shortwave antenna options to pair with a new SDR.

Indoor shortwave antenna options to pair with a new SDR

Keep in mind that if you’re fortunate enough to have a balcony, this is where you should mount your loop antenna. Check out this post by SWLing Post contributor, Klaus Boecker.

Klaus Boecker’s homebrew magnetic loop antenna.

Note that there are a number of sub $100 indoor amplified antennas on the market, but I would avoid using them–click here to read my thoughts about these.

In addition, read through this post which includes practical low-to-no-cost tips and best practices for shortwave listening at home and on the go.

Frugal SWLing: Investing little, but getting a lot out of your radio

I’m plotting to write a more in-depth article about antennas in the coming months, but it will focus on external antennas and methods of mounting them. When you have no means of mounting an antenna outdoors, in my opinion, your best options are the ones mentioned above.

Post readers: Have I overlooked an indoor antenna option? Please comment if you have experience with indoor antennas!

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Off-the-shelf affordable SWL antennas

The Par EF-SWL antenna.

One of our SWLing Post contributors recently sent the following message with a request:

I have a suggestion/challenge for a post: what’s out there for low cost, off-the-shelf HF antennas?

I simply can’t drop $500 on a Wellbrook. The AirSpy HF+ and the new $100 RSP1A SDR are super enticing, but then I look at the antenna connectors and think, “What do I have to connect to that…!?!”

Googling takes you down the rabbit hole of home brew antennas. I’ll admit that I don’t have the skill or patience to dig through hundreds of DIY posts of antenna construction. For my first proper outdoor antenna, I’d like to purchase one that’s rugged, well-tested and optimized for HF and MW listening. Something easy to install.

You know? I get it.

Many listeners simply don’t have the free time or enthusiasm to explore home brew antenna options especially if they’re seeking one optimized antenna for their location and listening habits.

Like it or not, antennas can become a barrier of entry to proper, low-noise radio listening and DXing.

I have built almost all of the antennas I use so I’m not an expert in this area, therefore I asked Fred Osterman at Universal Radio for a couple of suggestions. He and I have talked about antennas in the past and he’s the most knowledgeable person I know on the topic. I’m willing to bet Universal Radio stocks more SWL antennas than any other radio retailer. Fred also has the added benefit of hearing customer feedback daily.

I asked Fred specifically for wire antennas that are easy to install, require no soldering or tuning/cutting and work well right out of the box. Something under $200.

Fred replied with two recommendations–I include his comments in quotes:

Alpha-Delta DX-SWL Sloper $129.95

“[The Alpha-Delta DX-SWL Sloper] is very well built. Actually, over-built for listening. Easy to erect with the feed point being up high. And really works well on the SW bands (including Tropical) and MW too. Fully preassembled. Down-side is it is kinda obtrusive with the heavy wire and large coils.”

Click here to check it out at Universal Radio.

Par EF-SWL $72.95

“[The EF-SWL is very popular] these days. It does work best with a ground, but still usable without. It is interesting, as it can be configured many different ways. I suspect it is popular because it is very easy to erect, and very, very stealthy. (Increasingly important these days). And the wire is flexible, not too thick and not obtrusive. Seems more immune to noise than others. Priced right.”

Click here to check it out at Universal Radio.

Thank you, Fred!

I have some experience with the Par EF-SWL antenna. It offers excellent performance and the antenna line has a durable black coating that makes it nearly impossible to spot from a distance. I’ve even taken the EF-SWL on travels and posted a review a few years ago. I agree that it performs very well.

I have a friend that’s relied on the Alpha-Delta DX-SWL Sloper as his main SWL antenna for years. He lives in an urban area and I’ve been favorably impressed with its performance. I agree with Fred–it’s incredibly durable and beefy! Built like a tank.

Of course, there are also incredibly low-profile antennas like the Bonito Mini Whip (check out some of Oxford Shortwave’s posts) but note that some versions don’t handle a noise-rich environment very well.

Post readers: Please comment if you know of other off-the-shelf antenna options–especially those you have personal experience using and installing.

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Frugal SWLing: Investing little, but getting a lot out of your radio

This article originally appeared in the April 2014 issue of The Spectrum Monitor Magazine.


RadioDialLet’s face it: SWLers and amateur radio operators are some of the most frugal hobbyists out there.  But the good news is that radio is a hobby that favors the frugal.  There are many practical and time-tested ways to make radio listening fun and effective–such as improving your shortwave radio reception–that are absolutely free, or that cost very little.

And how do I know this?  Among the frugal, I’m the most frugal SWLer I know! Yet there’s a method to my frugal madness:  because I simply can’t afford to waste hard-earned radio money on gadgets and accessories that are ineffective, I count my pennies in order to make quality purchases with longevity in mind.  Meanwhile, I track down ways to keep my hobby cost-effective.

I’ve gathered here some of my favorite frugal tips and quality purchase suggestions here. So, without further delay, let’s start SWLing–and saving money.

1. Check your shack/home for RFI. Cost: Free

Checking your shack for RFI is vitally important, a procedure every radio listener or operator should undertake.

The truth is, very few of us regularly experience ideal conditions for HF or AM radio listening. Devices like plasma TVs, laptop power supplies, and the ubiquitous AC adapter inject distracting noise into our otherwise peaceful environs, disrupting our hobby. This noise is known as RFI (Radio Frequency Interference).

These "Wall Wart" type adapters can create a lot of RFI

These “wall wart” type adapters can create a lot of RFI

A number of times, I’ve received a message from one of my readers on the SWLing Post claiming that their new shortwave radio can “only” hear strong, blowtorch stations. My simple advice? Put batteries in your radio, turn it on to an unoccupied frequency in your favorite shortwave meter band, go to your circuit breaker box, and turn off everything in your house. (Warning: Do warn your housemates beforehand, to avoid any loud protestation! And do reset your clocks and check your refrigerator/freezer after this test.)

Did the noise level on your radio decrease? If the decrease coincided with the power cut, then one or more electronic devices in your house are generating RFI. RFI often sounds like static–very loud static–and is often so wide in bandwidth that it can cover several megahertz. RFI can overwhelm your portable radio and basically “deafen” it to anything but the loudest stations that break through the elevated noise floor.

Next comes the process of elimination: systematically turn on circuit breakers until you hear the noise return. If you’re fortunate enough to have accurately-labeled circuit breakers, you will at least know what area in your house holds the infamous disruptive device. Here’s a short list of the usual RFI culprits:

  • the ubiquitous AC adapter (aka, “wall wart”)
  • laptop power supplies
  • flat screen TVs: especially Plasma TVs
  • heating devices like electric blankets
  • external hard drives
  • lamp dimmers
  • touch lamps

Good luck tracking it down!  Chasing RFI can be complex.  Check out this list of RFI resources on the ARRL website for methods and ideas to cope with RFI.

2. Take your radio outside. Cost: Free

ParkListeningIf you live in a condo, high-rise, or high-density neighborhood, my first suggestion may be of little use to you. In this case, your neighbor(s) may be causing RFI; turning off your own power may have little to no effect.  Fortunately, there’s an easy–albeit modestly inconvenient–way to deal with neighborhood RFI. Leave the neighborhood! No, not permanently; just for a fun afternoon outing (with radio, of course).

If you live in a city, grab your radio, and head for a park or other area with wide open space and no buildings. Listeners who live in urban areas frequently enjoy radio listening via headphones on a park bench; some even have a favorite bench for their fair-weather pastime.

The benefits in this case are two-fold: firstly, you’re removing yourself from the vicinity of RFI, but secondly–and the icing on the cake–is that you’re taking your radio, and its antenna, outside.  Antennas always function better outside. Walls and even windows attenuate HF signals.  Plus, outdoor settings nearly always equal fun.

Want some inspiration? Check out how this SWL plays radio in central London.

By the way, if you have no local parks to which you can escape, consider taking your radio in the car and driving to a national park. Better yet, combine camping and SWLing.  I like to do this, although I don’t have an RFI problem where I currently live.

3. Make a simple wire antenna. Cost: Free (or, at most, $10-15)

Most shortwave portables radios on the market today have a telescopic whip antenna that will suffice for casual listening. But often you can increase the antenna gain by simply adding more length in the form of a simple thin wire. Keep in mind that many radios actually ship with a clip-on antenna wire. Check your original box and make sure you haven’t overlooked it, as it’s fairly easy to do.

An alligator clip offers serious bang-for buck--especially if you already have the parts lying around

An alligator clip offers serious bang-for buck–especially if you already have the parts lying around

If you didn’t receive a factory-supplied clip-on antenna, no worries!  They’re a breeze to make and quite cheap: indeed, if you have a junk box of electronics parts like so many hobbyists I know, you may already have what you need. Simply obtain a 20 foot length of jacketed (insulated) wire–gauge is not important, just something thin enough that you can easily roll up to transport. Next, strip ¼ inch of insulation off the end of the wire. Solder and/or crimp an alligator clip to the end of the wire, making sure you have a solid, stable connection.

Now, stretch out this wire and attach it to your antenna.  You will most likely find that this improves antenna gain. The effectiveness of the wire varies with the receiver. When I’ve made clip antennas in the past, I’ve simply made them longer than I thought I might need, then later cut it off at the optimum length based upon signal strength.

Two caveats:

  1. If you live in an RFI-heavy environment, adding a wire antenna at home may only increase your noise level (after all, it will make the radio better at “hearing” the noise).
  2. Some receivers are susceptible to overloading and electrostatic discharge (the Tecsun PL-600, Grundig G5 and G3 come to mind). To be on the safe side, do not attach any wire to your portable that is in excess of twenty feet in length.  Twenty feet should be more than sufficient length to increase antenna gain without any negative repercussions.

4. Use batteries––preferably rechargeable ones. Cost: $5- $20

Not all rechargeable batteries are created equally. Lean toward name brand, higher quality cells. Dollar store batteries lack longevity.

Not all rechargeable batteries are created equally. Lean toward name brand, higher quality cells. Dollar store batteries lack longevity.

This is one suggestion that may require a modest investment, but will pay off in more ways than one. I honestly can’t think of the last time that I listened to a portable radio while it was plugged into mains/grid power via an AC adapter. Since at least 2007, I have been powering my portables exclusively with good-quality rechargeable batteries.

Why rechargeables–? First and foremost, with rare exception, shortwave radio manufactures give little thought to the AC adapters they include with a portable shortwave radio; they’re simply an accessory that is expected, so they deliver. Indeed, the AC adapter that came with my Tecsun PL-880 (Tecsun’s latest flagship portable) came with an AC adaptor that does a great job charging the internal batteries, but injects copious amounts of RFI in the process. Running the radio off of batteries solves the problem instantly.

Many radio manufacturers now include rechargeable batteries with the purchase of a radio. Some of these batteries are AA cells, others are slim packs resembling cell phone batteries. Consider purchasing an extra battery if you’re worried yours might die away while you’re listening to your favorite program; a quick switch, and you scarcely miss a beat. If your portable comes with rechargeable batteries, most likely the radio even has a built-in charge control circuit.

I should add that I’m a fan of the traditional AA battery, even though they’re bigger than other battery types. After all, they’re nearly always accessible.  If a radio takes AA batteries, I never use the radio’s built-in recharger, instead I prefer a MAHA brand battery charger, as they condition and give a longer life to the rechargeable cells.

Sure, buying rechargeable batteries and, potentially, a good battery charger require an initial outlay of money, but the rewards are a quieter receiver and a more earth-friendly approach than heavy-duty or alkaline batteries can deliver.

5. Listen with headphones or earphones.  Cost: $0 – $100

Sony MDREX10LP in-ear headphones are inexpensive and effective.

Sony MDREX10LP in-ear headphones are inexpensive and effective.

Why headphones? Ask any serious DXers (amateur radio or SWL) and they’ll tell you headphones are an indispensable tool. While armchair listening is great with your radio’s built-in speaker, headphones give you better sound isolation, and your radio’s audio is equally balanced. Digging a weak station out of the ether is easier with headphones.

Almost every portable you buy today will come with a complimentary set of earphones. Quality varies amongst these, but in my experience, the headphones included tend to be of the lowest quality; for shortwave listening, these may suffice.

Though AM and shortwave radio is not considered a “high-fidelity” medium, thus not requiring a wide frequency response, I still prefer listening with quality earphones/headphones. As long as your headphones have a decent frequency response–I usually aim for 8 – 22,000 Hz–you’ll be pleased.  And do make sure your headphones or earphones are comfortable to wear for extended periods of time.

Yamaha CM500's are a worthwhile investment if you're an amateur radio operator.

Yamaha CM500’s are a worthwhile investment if you’re an amateur radio operator.

One of my favorite pair of in-ear earphones for SWLing are the popular Sony MDREX10LP series. They’re comfortable, responsive, isolate noise, and are available from a number of retailers for about $10 USD per pair.

For over-ear headphones, I like the Panasonic RP-HTF600. They’re large, comfortable, and deliver amazing fidelity for about $30 USD.

If you also happen to be an amateur radio operator, the Yamaha CM500 headphones have a built-in boom mic that works amazingly well.  At $50 USD, they are a steal. When I received mine, I opened the package, plugged the headphone and mic jacks into my Elecraft KX3, and I was on the air with them in seconds.

6. Learn to use use Exalted Carrier Reception (ECR/ECSS). Cost: Free

ECSS-PL-660“Exalted Carrier Reception” (ECR) a.k.a. Exalted Carrier Single-Sideband (ECSS) is just a fancy way of saying that an AM broadcast carrier is tuned in while in single-sideband mode. This is most useful when you’re trying to listen to weak broadcasters.

This (ECR) is, in a sense, the frugal listener’s version of synchronous detection. Why does it work?  As my knowledgeable ham buddy Mike (K8RAT) explains: ”You’re removing any selective fading problems by filtering away one of the sidebands, and injecting a carrier of steady amplitude which eliminates the ‘tearing’ heard when a broadcast carrier is varying in amplitude.”  Got that?

Even if you don’t understand it exactly, here’s how to use ECR:  Simply find a strong AM station on your radio.  Next, turn on the BFO or SSB mode on your radio. As you adjust the tuning knob, you’ll hear an audible whine, the pitch of which will change with every increment of tuning. “Zero-beating” the carrier follows next–this is simply tuning in the signal until that whine is gone, and the AM station can be heard as clearly as if the radio were in AM mode.

The fidelity of ECR/ECSS is typically not as good as AM–mainly because SSB filters are usually narrower than AM filters–but it does lower the noise floor, increase the stability of the received signal, and make this signal “pop out” a bit more.

But don’t take my word for it–let your ears be your guide! In this recording, I tune in a low-power station on my receiver in standard AM mode, but at 15 seconds into the recording, I switch to the upper-sideband (SSB) mode, zero-beat the frequency, then open up the SSB filter a little wider.  Then, just before I end the recording, I switch to lower-sideband–something you can do if there is interference in the upper-sideband, for example:

It’s amazing how much background noise ECR removes.

If you’re lucky enough to have a tabletop radio, chances are it has an SSB mode (although there are some very rare exceptions). Less than a third of portables on the market, however, have SSB. Here is a list of the most popular portables with SSB that are, or have recently been, in production.

7. Use a web receiver.  Cost: Free

If you live in an area with frustrating RFI, but want to listen to the shortwave bands from home, try an online web-based receiver. Sure, it’s not quite like tuning a radio at your fingertips, but it’s the next best thing, and also a handy tool for checking propagation or verifying your own signal (if you’re an amateur radio operator).

My two favorites site are:

  • GlobalTunersGlobal Tuners which has a number of remotely-controlled radio receivers all over the world. You must register before you can participate, but registration is free. Global Tuners even has a free Android app that permits remote receiver control via your smart phone or tablet.
  • utlogo4bThe University of Twente Wide-band WebSDR is an amazing resource. Not only can you control this receiver, but so, too, can a few dozen other web guests––all at the same time! I’ve used U Twente’s receiver on a number of occasions to listen to European pirates. Cost? Again, it’s free.

8. Finally, practice listening. (Cost: Just some time)

SP600Dial3My final bit of “free” advice sounds a little philosophical, but rest assured, it isn’t.

I’ve always likened radio listening to another of my interests, astronomy–an entirely different hobby that, unless you’re a radio astronomer, relies on an entirely different sense.

Why the comparison?  I’ve known some talented astronomers that, with just a basic pair of binoculars, can see much more in the night sky than I ever could. Are their eyes better than mine? Not necessarily. Their eyes are just experienced in the field of stargazing; they know what to look for, and most importantly, what to appreciate. Their brains decipher the images of bright or faint stars, subtle variations in color or shape, and focus on what they consider important. In short, this is not an ability you can pick up overnight; it takes patience, experience–and true passion.

Radio listening is, in that sense, much the same. Though I’m by no means a good example, I do wish I could go back to the days of my youth with the ability to listen that I have developed over the decades. There must have been so many jewels of stations hidden in the ether that I completely skipped over…My ability to, for example, pick out the ID of a faint station, to tune accurately and quickly, and to cope with adjacent noise, have all been honed since then, a result of time spent just listening.

My good friend Vlado (N3CZ) is a case in point: he is one of the most capable ham radio DXers I know. His extraordinary ability to pull intelligible conversations and CW (Morse code) out of the static, even in crowded radio conditions, is simply astounding. Vlado’s main transceiver is nearly two decades old, and by no means a benchmark technically. If you ask Vlad if he uses filters and digital signal processing, he will wisely tell you, in his Macedonian accent: “Your best filter is between your ears.”

The same goes for SWLing. I have spent enough time listening to shortwave and weak DX that I can now pull conversations out of the noise that my (non-radio) friends can barely detect. I’m convinced this is healthy exercise for the old grey matter.

David Goren, good friend and the highly-creative radio producer behind Shortwaveology.net, describes how shortwave listening enhanced his career:

“When I first discovered shortwave, I’d strain my ears through the static and all the layers of jumbled up sounds trying to hear as far around the world as I could. Years of this kind of intensive listening tuned my ears in such a way that allows a laser-like focus on the sonic details when working in the production studio making radio stories.”

Indeed, I’ve heard and can certainly appreciate the results of his remarkable “laser-like” listening ability; check out Shortwaveology.net for your own experience of David’s talented ears. You’ll be glad you did.

No doubt you enjoy listening already; my contention is that it has more benefits for your brain than Sudoku puzzles, and iis even more fun. Plus, did I mention that it’s free? You don’t need to pay a subscription to listen to the radio. There’s no real trick to this: it just takes time…interest…and a pair of ears.

Happy listening!

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