Monthly Archives: July 2017

Guest Post: Old School Infrared Wireless Headphones

Many thanks to SWLing Post contributor, Mario Filippi (N2HUN), who shares the following guest post:


Old School (Infrared) Wireless Headphones

by Mario Filippi (N2HUN)

Have you ever mindlessly walked away from your TV with headphones/ear buds still tethered, causing all sorts of havoc? Been there, done that hi hi! Let’s face it; there are plenty of avenues to remedy the situation by upgrading to wireless headphones. Nowadays most state of the art wireless headphones use radio frequencies to achieve a wireless method of listening. For example, my XYL blissfully listens to TV audio with Sony stereo wireless headphones, using a frequency of 915.5 MHz; below is the actual signal viewed with an RTL-SDR dongle.

Sony wireless headphones signal viewed via a SDR dongle; FM modulation.

But hold the presses: there’s good news for folks not averse to old-school technology.

I recently purchased a set of RCA wireless headphones using infrared technology from shopgoodwill.com.  Yes, those of us who are somewhat long in the tooth remember infrared as the common method for consumers to “cut the headphone cord” way back when.  Infrared is located just above the radio frequency spectrum starting around 300 Gigs (Gigahertz) and is still commonly used in TV and satellite remotes, but less so now with modern wireless headphones operating in the  900 MHz  and 2.4 GHz ISM (Industrial, Scientific, Medical) bands.

Admittedly, the new breed of wireless headphones possesses an array of options not available with older infrared units, but if you are satisfied with a no-frills method of headphone freedom (well about 25 feet range that is), check out the pre-owned inventory offered on shopgoodwill.com.  The pair I purchased started at  $7.99 with no other interested bidders so the total with shipping was $16.82 with the original box and was complete, including the rechargeable NiCad batteries which still functioned but undoubtedly will need replacing.  To boot, the money went to a charitable organization.

Wireless IR stereo headphones from shopgoodwill.com

Interestingly, I tried using the wireless IR headphones in conjunction with a shortwave receiver (Panasonic DR22) but there was lots of interference, evidently from the IR transmitter; shortwave and the AM BCB were wiped out by the interference. Now on the FM BCB it worked fine. Even tried it with a scanner and it seemed to work well with FM transmissions (police, fire, EMS) but not with aero AM (108 – 136 MHz).

In the end my venerable older headphones have been relegated to the “shelf of infrequently utilized equipment.” Radio hobbyists might want to visit www.shopgoodwill.com as there are lots more radio memorabilia for window shopping or adding to one’s armamentarium. Remember to read the descriptions carefully as to the working condition. In the interest of full disclosure, I am not associated with ShopGoodWill in any way except that I’m a very satisfied customer. And yes, there are new, state-of-the-art wireless headphones available at a comparable price, so why the reason for this tale? Well, for knowledge, a little history, and a dash of sentimentality, that’s all! hi hi!


Thanks, Mario!

I briefly worked in a RadioShack store in the mid 1990s. We had a set of IR wireless headphones on display and hooked up to a receiver. I remember putting them on and listening to music after/before store hours completing mindless tasks like inventory, clean up, etc. It felt incredibly liberating to walk around the store without a headphone cord umbilical cord! The IR footprint covered the entire store, but fell apart if I had to duck below an end-cap or shelf partition.  

Thank you for taking us on a wireless stroll down memory lane, Mario!

FCC Chairman Ajit Pai questioned about pirate enforcement

FCC Chairman Ajit Pai

(Source: Tom Taylor Now newsletter)

FCC staff will be “cops on the beat” against pirates.

Chairman Ajit Pai had his stats ready for yesterday’s House Oversight Hearing – the FCC’s issued 39 NOUOs (Notice of Unlicensed Operation) this year, among other enforcement actions. Pai knew the question about the effect of closing of 11 field offices was coming from somewhere, and it was posed by Tampa-area Republican Rep. Gus Bilirakis. Pai says as a Commissioner, “I had substantial disagreements with the original” plan of then-Chair Tom Wheeler. The compromise worked out with Congress included closing the Tampa field office – but Pai says the Commission’s doing its best to address the pirate problem that is “a problem all across the East coast.” That when he says the staff is determined to be “cops on the beat” against unlicensed operators. That seemed to satisfy Bilirakis. More from the hearing – there’s support for a new minority tax certificate plan. It would incentivize an owner to sell to a qualified minority by offering a tax break or deferral. And we haven’t mentioned the #1 complaint around telecom – doing something to choke off robocalls and “spoof calls.”

Check out the full Tom Taylor Now newsletter which also includes questions posed to Chairman Pai, about defining Net Neutrality.

Operator shares what it’s like to work for a numbers station

(Source: Numbers Stations)

Working at a numbers station 6 decades ago was not much different than working at an AM broadcast station. Located on a WWII old Naval Base it consisted of one building surrounded by a double chain link fence inside which older local men drove pickup trucks around for security. Inside the building there was a workshop, two 20,000-watt AM shortwave transmitters, crystal controlled oscillators, and a soundproof booth with a record player and records of well-known music in a language and culture common to the target. Outside the compound was an antenna farm with a log periodic antenna, a rhombic, and a couple dipoles.

I lived, with my wife, about a mile from the site and would drive through a back road to the location, be admitted by security through each gate, and park, and relieve the other op who, after briefing me, was free to go home. My job was to follow a schedule, select the proper frequency at the proper time, tune the transmitter, hit the plate voltage, play the record the schedule told me to, and then recite the messages arranged in five-number groups of numbers in the appropriate language into the microphone in the recording booth. This was all done live and, as far as I know, no recordings were kept.

[…]Other than that it’s just a job. The messages were all prepared somewhere else by someone else and delivered to us along with the schedule. We all had high level clearances but we never knew who we sent these to or what the real ones might have said. This sort of compartmentalization was (and is) common.

I often thought of those for whom the messages were intended… how they felt, where they were… whether they were in an attic or shed or stranded somewhere copying down a message that was a threat to their very lives on a radio that was a death penalty to simply be in possession of. I was very careful to do it right.[…]

Read the full article at Numbers-Stations.com.

A birthday message from Ian McFarland

Many thanks to Colin Newell who forwards the following birthday message from Ian McFarland:

Ian McFarland receiving his birthday card filled with your messages. (Photo: Colin Newell at DXer.ca)

To all my SWL friends & colleagues,

I can’t tell you how much I enjoyed reading all your birthday wishes & comments that Colin so kindly collected & transcribed from all your e-mails. For this old man it was a most enjoyable exercise in pure nostalgia. Thank you all so very much! There were lots of familiar names on those messages, and of course, to be truthful, lots of names that weren’t familiar after so many years. Memory loss is, after all, one of the unfortunate drawbacks of getting to the age that people refer to as “elderly”!

I find it hard to believe that I retired from RCI over a quarter century ago now, mercifully, some years before its impending virtual destruction over the next few years. I’m just grateful that I was at RCI during almost 25 years of RCI’s heyday. I’m also grateful for all the opportunities I had to travel to Europe, the U.S. and other parts of Canada to attend a variety of SWL gatherings and have the opportunity to talk with so many of my listeners. I’m sure that over my years at RCI I met many times more listeners than the rest of RCI staff and management combined.

Attending all those events, including the three ANARC conventions that were hosted by RCI, gave me many useful insights into what our listeners liked to hear about, and the determined efforts they made, especially in the noisy interference ridden listening environment in Europe, to tune in to my SWL Digest program. I can’t tell you how much that meant to me. Many thanks again for all your wonderful birthday wishes & comments.

Cheers for now & Good Listening everyone.

Kind regards.

Ian.

Richard’s initial impressions of the Sony XDR-S41D FM/DAB receiver

Many thanks to SWLing Post contributor, Richard Langley, who recently attended a conference in Paris and picked up a Sony XDR-S41D. Richard writes:

The workshop closed around noon on Friday so I spent part of the afternoon walking around the nearby Darty consumer electronics and appliance store.

I wanted to buy a DAB/DAB+ portable receiver just to see what Europe was doing with digital radio. I bought a recently introduced Sony XDR-S41D DAB/DAB+/FM(with RDS) receiver for 79€ (about 11€ off list price).

I can use it in North America to listen to FM and take it with me when I visit Europe for DAB/DAB+ as well as FM.

It has reasonable sound from its 8-cm speaker and pretty good stereo sound on headphones. It has an automatic search mode on both DAB/DAB+ and FM and creates a list of available stations.

In my hotel room in the 13th arrondisement, I could receive 46 DAB+ stations. One of the stations is World Radio Paris (WRP) and they provide English language programming 24 hours per day from BBC World Service, Public Radio International, Radio France International, and Radio Canada International, among others as well as their own programming.

Another available station was Medi 1, which just dropped its shortwave transmissions. I recorded some of the WRP programming:

Audio Clip 1 (MP3)

Audio Clip 2 (MP3)

There is no line output from the receiver but I was able to use the earphone output and crank the volume to maximum to get an acceptable recording level without noticeable distortion.

Happy with my purchase and can’t wait to go back to Europe again, say to England, to try out DAB+ there.

I also spotted three receivers with SW capability on the shelves at the Darty store:

  • Panasonic RF-3500 for 45€
  • Brandt BR200D for 45€
  • Brandt BR120A for 15€

You don’t see SW receivers in North American consumer electronics stores anymore and I’ve not spotted any in airport duty free stores lately either.

I’ve been listening to the XDR-S41D at home and it sounds pretty good on FM, too, and does a good job of displaying the RDS information although a character or two is sometimes cut off the end of the data but that could be the fault of the station. Need to investigate that some more.

By the way, the radio doesn’t come with a case but I found (just before I was going to toss it) that it just fits in the magnetic-clasp case of one of those Air Canada amenities kits that they give you in business class (see photo below).

That’s the second Air Canada item I have recycled. They used to use full-ear headphones with disposable foam covers. They were a perfect fit for the deteriorating covers on my old Sony noise-cancelling headphones. I’ve since upgraded to Bose. 😉

Thank you for sharing your thoughts, Richard! The Sony XDR-S41D sounds like a keeper for sure and is certainly compact enough to easily accompany you on travels to Europe. I was not aware of World Radio Paris either–I see they’re available via TuneIn, so I’ll add them to my WiFi radio station favorites!