Category Archives: Mediumwave

Tecsun S-8800 update

UPDATE: Click here to read our full review of the re-engineered Tecsun S-8800. Note that the post below refers to the first production run units only.

If you’re considering purchasing the Tecsun S-8800, this is an important post.

I’ve had the S-8800 for about two weeks and had planned to have audio clip comparisons prepared and posted by now. My exceptionally busy schedule has made this difficult–and there a few other complicating factors.

First off, the good news: in terms of sensitivity, selectivity and audio fidelity, I’m very happy with the S-8800. I’ve compared it a number of times with the Tecsun PL-880 and the Sony ICF-SW7600GR and it either holds its own or even has a leg-up on both radios in terms of overall performance. I find that the S-8800’s AGC is more stable than my 1st generation PL-880.

Of course, what will be most telling is what you, dear reader, think of the performance when compared in a blind audio test.

As I mentioned, though, there are complicating factors–It’s not just my schedule which has made the S-8800 review come to a halt.

Birdies…

Yes, birdies. Lots of them.

At first, I thought the noises were due to the fact my mobile phone and Zoom H2N digital recorder were too close to the S-8800. I dismissed this interference as it didn’t sound like the typical steady tone/carrier birdies I’ve come to loath over the years.

As my testing continued, though, I quickly realized these variable heterodyne and digital hash noises must be internally-generated.

Quite literally, as I was outdoors testing the S-8800 and making this discovery last week, I received a message from SWLing Post contributor, Bertrand Stehle (F6GYY). You might recall, Bertrand provided us with an initial review of his S-8800e (the European version of the S-8800). He also started noticing the birdies and, like me, initially assumed they were due to an external source of RFI.

Bertrand kindly mapped out the extensive list of birdies he found on his S-8800e–he noted a total of 81 birdie/carrier locations:

14 birdies on longwave
4 birdies on mediumwave
63 birdies between 1859 – 29095 kHz

Comparing notes, there are some differences between Bertrand’s S-8800e and my S-8800:

Only 50-60% of the birdies on my S-8800 are in the same frequency locations as those mapped by Bertrand on his S-8800e
The total number of birdies, however, are likely identical–I find birdies where Bertrand hadn’t noted them

The appearance and intensity of the birdies can vary depending on listening location and the strength of any nearby broadcast signals. I’ve noticed four distinct birdie sounds: a variable carrier, a steady carrier, digital hash, and something I might describe as digital variable noises.

I’ve even noticed some change slightly as you move the radio around.

Here are a couple of examples:

Example on 610 kHz:

Click here to view/listen via YouTube.

Example on 2009.15 kHz:

Click here to view/listen on YouTube.

Moving forward

Obviously, this is a major issue for an enthusiast-grade portable.

I’m sharing all of this information with Anna at Anon-Co. No doubt, she’ll share this information with Tecsun engineering. The last I heard, projected availability of the S-8800 from Anon-Co is late March 2017. Perhaps there will be time for Tecsun to eliminate these birdies by improving internal grounding and/or shielding?

Until the birdie issue is sorted out, I’m not proceeding with audio comparisons or a full review. It goes without saying that, at present, I couldn’t recommend purchasing the S-8800. Sad, because this is otherwise a great radio.

I hope Tecsun can sort this out, though.

I will share any/all updates here on the SWLing Post.

Follow the tags S-8800 Birdies or S-8800.

A quick view of my shack in Oxford, UK & recent transatlantic medium wave DX

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Someone recently described my shack in Oxford as ‘an impressive mess’…. and that really is just about the most positive comment I’ve ever received regarding my listening post! So, my apologies for displaying the mess in public, but in response to having been asked many times by subscribers to Oxford Shortwave Log to ‘share my shack’, here it is, well most of it at least, in all it’s unadulterated glory.

The primary reason however for this post is to share my most recent transatlantic medium wave catches using the brilliant Elad FDM DUO and Wellbrook ALA1530 magnetic loop antenna. This excellent combination continues to pull in really nice DX, although not so much very recently as propagation has been fairly rubbish. However, since early to mid December, the dynamic duo have managed to pull in a number of transatlantic medium wave signals, including Radio Rebelde, Cuba on (670 and 710 kHz), KVNS Texas, CHIN Radio, Toronto, WFED Washington DC, WWNN Health and Wealth Radio, Pompano Beach, Florida, and huge signals from WMEX Boston and WWKB Buffalo, New York. Embedded reception videos and text links follow below and in the mean time, I wish you all great DX!

Click to watch on YouTube

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Dave once forced the Shipping Forecast to repeat a broadcast

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Droitwich transmitting station (Source: Wikipedia)

Our post yesterday regarding the Shipping Forecast reminded me of a story SWLing Post contributor, Dave Porter (G4OYX) once shared. Dave writes:

I worked at the Droitwich Transmitting Station through 1972-1974, the home of the BBC UK Long Wave 1500 m/200 kHz service as it was then.

In the summer of 1973 I was junior member of the engineering team, a 21 year-old Technical Assistant, and manned the control room for the four services from the site, Radio One, 1214 kHz, Radio Two, 200 kHz and Radio Four, 1052 kHz.

It was customary to check the two 200 kW transmitters, T7A and T7B for power balance prior to the Shipping Forecast and I duly went out in the transmitter hall just before the start at 1355.

I noted one was a little down and the other a little high so I pressed what I thought was the raise / lower buttons on the control desk. Unfortunately I had pressed the main on/off buttons instead.

The pair of transmitters came instantly off the air. I could hear on the audio monitoring the announcer starting the broadcast… it takes a while to reinstate the mercury arc rectifiers as the regulators had to run all the way down to zero and then back up to 14 kV.

By the time I had got it back on the air he was just finishing so we had to contact London and arrange a repeat after the 1400 news bulletin… Ooops!

I was much more careful after that when adjusting the transmitters.

The Senior Maintenance Engineer was not best pleased, as he had to write up the shutdown report for London citing “Operational Error” as the cause.

Happy Days…

Dave G4OYX.

That’s a brilliant story, Dave! Thank you so much for sharing. Oh…I’m sure it’s a lot easier to laugh about it now than it was when it happened! 🙂

Video: Juan touts Panasonic RF-2200 performance & filter shapes

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Many thanks to SWLing Post contributor, Juan Pablo Carlino, who writes:

Hi. I own one RF-2200 after buying it in eBay in March 2008. Since then it became my favourite portable radio and as everybody [has commented], its a pleasure to hear MW with it.

I explain this due to the fact that it has a good rotative ferrite antenna and also because the narrow and wide filters have a suitable shape for MW: at least in my country each MW is spaced from the other by 10 KHz, so you don’t need a very sharp filter. The narrow one is not so narrow, just enough to attenuate maybe 6 db the splatter from the louder station and not loosing audio quality.

When you tune around you have the impression that the filter shape suites perfectly for MW, making the audio quality very pleasant. I would never sell it. If you are interested i’ve captured a short clip while playing with it outdoor on 7 MHz band, hearing ham stations on AM, SSB and CW.

Pay attention to how loud and clear i was hearing stations at 400 Km in AM:

Click here to view on YouTube.

Many thanks for sharing your thoughts, Juan!

I agree with you completely. At least here in countries where MW stations are spaced at 10 kHz, I find the RF-2200 a mediumwave DX boss!

I’m constantly amazed with the RF-2200’s MW sensitivity and selectivity–and low noise floor. That combo, along with the filter shapes Juan mentions and the excellent built-in full-fidelity speaker make for a proper listening experience.

As I’ve said before, the RF-2200 is a radio with fortitude and purpose.

The only place I’ve ever really searched for an RF-2200 is eBay. I like eBay, because if you receive a faulty unit, you can typically return it or have some sort of recourse (as long as the seller accepts returns).

I would only buy an RF-2200 (or any vintage solid-state rigs) from a seller that has near 100% ratings with a number of radio sales in their past. That is, if you’re seeking a working unit.

Though the RF-2200 is vintage and thus might eventually need repair. It’s ultimately reparable by a skilled technician, though. My buddy Vlado, for example, has repaired 2200s in the past–indeed, we cracked my RF-2200 open a few months ago to clean contacts.

Panasonic RF-2200s typically cost between $175-300 for one that’s mechanically and cosmetically sound. Of course, NOS units go for much more and units with faults sell for much less.

I expect my RF-2200 will outlast me!

Click here to search for RF-2200s on eBay.

The Eton Satellit: a poignant recording of ABC Northern Territories & further DX…

Tecsun S-8800: Unboxing, photos, and initial impressions

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UPDATE: Click here to read our full Tecsun S-8800 review.

Yesterday, I received a Tecsun S-8800 from Anon-Co in Hong Kong.

I like opening radio boxes to find a cardboard insert like this one. It protects the radio and has so much less waste and individual cardboard bits inside.

As I always do when a new radio comes on the scene, I requested to purchase an early release of the Tecsun S-8800 radio for review months ago. But this time, my contact at the Chinese distributor Anon-Co, Anna, insisted on sending us one “as a gift for the Chinese New Year of the Rooster.”

Because I’ve worked with Anna at Anon-Co for at least a decade, having purchased numerous radios for review and as gifts for family and friends, this was difficult to refuse. I decided there was no need to do so. Each time I do an in-depth review and note shortcomings or deficiencies in the radios I’ve purchased from Anon-Co, Anna immediately passes my feedback and criticisms directly to the manufacturer’s engineers. I believe this feedback loop between customers, reviewers and manufacturers leads to improved product iterations. Of course, sometimes the negatives can be so problematic, manufacturers simply drop the product line and move on (remember the Tecsun R-2010D? Case in point). So, while there are a number of other eBay retailers in China that distribute Tecsun radios, I prefer Anon-Co for these reasons.

Thank you, Anna!

The S-8800 is packed face-down to protect the front panel.

Manufacturers and retailers who send me products for review know that we radio geeks have fairly high expectations of our gear, and will therefore hold them to exacting standards. I’m not the least among these. While I endeavor to be realistic, understanding producers’ limitations and the need for product growth, I also try to keep my reviews as objective as I can, and accommodate my own and others’ particular requirements and preferences.

So In the spirit of full disclosure, I must note that I’m not as avid a user of large portables like the S-8800 (or the Grundig GS350DL, S450DLX, or the C.Crane CCRadio-SW).

Personally I prefer smaller, full-featured travel-friendly portables, or else larger tabletop models. Radios with a form factor like the Tecsun S-8800 are an “in-between” product in my world, thus I rarely use them.

That said, every month I receive questions from readers looking for this very “large portable” form factor. Some hobbyists enjoy a radio that’s easy to operate, featuring simple controls, robust audio, and dedicated external antenna connections. For these listeners, a large tuning knob and generous display are more important than things like SSB and synchronous detection.In other words, they want a broadcast receiver. Some have literally asked for a modern version of the venerable Panasonic RF-2200 (which I admittedly love, an exception to the rule of my avoidance of large portables). In terms of aesthetics, it’s impossible to live up the legendary solid-state RF-2200, in my opinion…kind of like comparing a modern muscle car with the 1960s original from which it copies its design.

The S-8800, and its many predecessors, were certainly influenced by the RF-2200’s popular design & form factor: large speaker on the left, large tuning knob, wide-spaced knobs, and a generous display. Like the RF-2200, it has a durable, adjustable woven carry strap.

The S-8800 ships with the accessories in the photo below: an IR remote control, two rechargeable cells, an RF adapter, and a USB charging cable.

Note the charging cable is only a cable; the S-8800 doesn’t ship with a wall-wart type charger. If you’re like me, you probably have a handful of USB chargers scattered around your home that you could use for the purpose of charging this radio. And if you don’t, you can also use any free USB port on your PC to charge it.

USB chargers are cheap and well-known to spew RFI. I doubt you’ll enjoy listening to shortwave or mediumwave/AM while charging the S-8800’s internal cells. It doesn’t appear the S-8800 was designed for listening while plugged in; Tecsun clearly wants you to charge it and then listen, off battery power. The latter is my preference for listening anyway, but it may put off some potential S-8800 owners.

The display is easy to read from any angle, and it’s also easy to view in bright sunlight. In low light, you’ll be pleased with the backlight function.

On the right side of the S-8800, you’ll find an internal/external antenna switch, a DX/local switch, RCA type stereo line-out ports (covered in the photo above) and a stereo headphone jack.

On the back, you’ll find a mini USB port for charging, an antenna port for a radiator and ground wire, as well as an FM antenna port.

The battery cover is predictably located at the bottom of the back panel and––a first for any shortwave radio I’ve reviewed––accommodates two (supplied) 3.7V Li-Ion (internally) rechargeable cells.

The right side panel has no connections or controls.

I must admit…the Tecsun S-8800 has some front panel controls I really appreciate. Most notably, it has a dedicated AM bandwidth selector and fine tuning control. I also like the dedicated treble and bass controls which can also be found on its predecessors’ front panels.

Over the next week, I’ll be evaluating the performance of the S-8800. I plan to post blind audio samples as I’ve done in the past, comparing the S-8800 to other portables: likely the PL-880 and the ICF-7600GR, PL-660 or PL-680. Please be patient, however, as making these recordings takes time as I like to make sure each radio has a true representative sample and fair shot at showcasing performance.

What about those initial impressions? Yes, I must say I do like the package of the S-8800 better than its predecessors. I like the dedicated IR remote control, the many antenna connections, and, so far, the audio fidelity from the built-in speaker. Makes for a nice package.

But, ultimately, the proof is in the pudding: let’s put the S-8800 on the air and compare it with some benchmarks!

Follow Tecsun S-8800 posts by bookmarking the tag: S-8800

A New Approach to FSL Antenna Construction

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Introduction

I’m very fortunate to live across town from my good radio hobby pal Gary DeBock. He has been responsible for the rapid growth in Ultralight radio DXing and the construction of Ferrite Sleeve Loop (FSL) antennas. Living near each other as we do, I’ve benefited a lot from his expertise and creativity in the hobby. We’ve enjoyed visiting about Ultralight radios and antennas many times over a leisurely lunch. If you’re unfamiliar with Gary’s efforts, just do a YouTube search on his name and see just a few of the many FSL antenna variations he’s built!

Gary uses PVC tubing, “Fun Noodle” foam cylinders, sections of curved foam, and rubber plumbing adapters almost exclusively as the core supporting structures for his FSLs, from small 3-inch models to 17-inch monsters. Gary certainly has perfected his own techniques with these raw materials; he’s an expert in combining them. He even makes PVC table structures to support his FSLs during Oregon coastal DXpeditions, as seen in some of his YouTube videos.

These materials work well, but over time even FSLs as small as 7 to 8 inches in diameter begin to sag and lose their perfectly circular shape. This seems to be caused by the shifting of individual segments of foam which are wrapped around a “Fun Noodle” core and center PVC tubing.

What possibilities are there for other materials in FSL antenna construction? It would be a fun challenge to build a small to medium sized FSL antenna that would have these qualities:

Maintain a circular cross-section without sagging
An appearance less like a threatening explosive and more like a commercial product
Use alternate construction methods for those not skilled with cutting & gluing PVC tubing

I began to keep my eyes open for likely candidates as I visited hardware stores, department stores, and office supply outlets. Eventually some ideas began to gel.

Raw Materials

Here is a visual and descriptive list of what I used in this alternate design of Ferrite Sleeve Loop antenna. I won’t go into great detail about dimensions, quantities, and measurements, as other DIYers should be able to easily follow the general idea presented here. This article is mainly to get you thinking about other ways to construct a ferrite sleeve loop antenna.

The Core of the Matter

This 18-inch long, semi-rigid foam roller is six inches in diameter. It’s a workout and exercise aid which I found in the sports department of my local Walmart store. The cost was approximately $13. This one-piece foam is a perfect foundation for holding and protecting the fragile ferrite rods and keeping them in a circular arrangement; since the roller is in one piece there is nothing to shift around, or sag. When placed on this core, the final diameter of the FSL antenna is approximately seven inches.

So, what to put the antenna in? Something needs to suspend and protect the antenna as a substitute for the PVC frame previously used. This Sterilite tote box is the perfect size to hold the antenna. As shown in the photo, the dimensions are approximately 14-1/4″ X 9-5/8″ X 12-1/4″; the model number is 1896.

Early on, I decided that the flimsy “locking tabs” on the cover would not suffice for holding the relatively heavy antenna when carrying the tote by the handle. I drilled holes and attached a dozen small Nylon nuts and bolts to secure the cover. (Nylon avoids distorting the medium wave reception pattern of signals, as metal hardware could.)

An ample quantity of 200mm ferrite rods are needed, plus a air variable capacitor (preferably with a 8:1 reduction drive shaft), and Litz wire. 1162 strands/46 ga. Litz provides the most sensitivity but the coil will cover a greater width on the rods.

Gary likes to use waterproof medical tape, sticky side out, to hold the rods in place, but I like to use Gorilla brand tape, as it is extremely sticky and holds the rods better. My choice for the rod-to-coil spacing material is two turns of 1/8″ thick bubble wrap.

This is the foam core, ferrite rods, bubble spacer, and coil assembly prior to fitting in the Sterilite tote container. Before assembly to this point you’ll need to cut the foam roller to length using a serrated knife or electric carving knife. Two sturdy cable ties help hold all of the rods in place. A better alternative might be strips of 1/2″ wide Velcro straps purchased from a fabric shop or home improvement store.

Another key item to this construction method is the use of plastic drywall anchor screws. These are meant to be pushed and screwed into gypsum wallboard for sturdy attachment of bolts or picture hangers on walls. When screwed through drilled holes in the side of the Sterilite tote, they secure and suspend the foam roller/ferrite sleeve loop assembly. The density of the foam roller is sufficient to give a good grip to the drywall anchors. Eight to ten anchors per side are enough to hold the assembly in place. See the photo at the beginning of this article for a good view of this mounting method.

Every good FSL antenna design needs an official sounding manufacturer! With tongue firmly in cheek I’ve appropriated the name shown on this self-produced label. Clearly, a Ferrite Sleeve Loop antenna from Naughtabaum Ferrite Specialties Ltd. stands a better chance than most of passing through TSA checkpoints, right?

I hope this article has given you some new ideas for FSL antenna designs. There’s certainly room for improvement, including making the antenna’s ferrite rods look less intimidating…less like a bundle of dynamite! Perhaps the entire assembly can be wrapped with something that shields the rods from view, or you could use an opaque tote container rather than a clear model.

Be on the lookout for useful materials to repurpose. Trips to your local home improvement stores, office supply, and other outlets will give you further ideas on how to design your own Ferrite Sleeve Loop antenna.