Author Archives: Jock Elliott

DXing . . . bats?!!

by Jock Elliott, KB2GOM

Just how hardcore are you as a DXer?

I received the following from a ham radio friend:

Greetings all!

I received an interesting opportunity for anyone capable and interested
in helping NYS DEC. This was aimed at Warren County, however I thought
hams in the Northern District surrounding counties could also assist,
particularly Saratoga and Washington counties:

We were recently contacted by a representative of NYS DEC, Fish and
Wildlife Division requesting the assistance of the amateur radio
community. The DEC will be releasing approximately 20 bats with
transmitters attached and hope to track them to their summer roosting
locations. They are scheduled to be released on April 22 at Hague, NY.
The frequencies for these transmitters will be in the 150-151MHz range
and are included below. They will emit about 35 pulses per minute. The
idea is to set up your radio to scan the frequencies (by entering each
one, or scanning from 150-151MHz in 1KHz steps). Should you get a “hit”,
note the frequency and cross it to the serial number of the transmitter.
Note the date and time and report it to me.

This sounds like a fun exercise and we will be helping the DEC as well.
If you think you will be participating, let me know. I’d like to report
back to the DEC representative with an approximate head county.

Thanks and ’73

Mark KD2RJP

Serial # Frequency
276481 150.052
276482 150.075
276483 150.109
276484 150.172
276485 150.192
276486 150.272
276487 150.290
276488 150.351
276489 150.391
276490 150.429
276491 150.449
276492 150.513
276493 150.549
276494 150.571
276495 150.592
276496 150.670
276497 150.690
276498 150.751
276499 150.794
276500 150.829
276501 150.850
276502 150.875
276503 150.916
276504 150.951
276505 150.990

Update:
The release date has been moved to April 22.
One thing I didn’t mention in the original emai l: the transmitters
will work for about 2 weeks. So please scan when and where you are able
to within the 2 week period. Also, many radios do not have the ability
to tune in 1 KHz steps so your radio may not be able to monitor all the
transmitters. Scanners may work. Regardless, do the best you can. If
you are planning to participate and haven’t already notified me,
please let me know so I can notify DEC how many stations will
participate. Finally, here is the data sheet sent by DEC to help log
any “hits” you might get. If you get any “hits”, please send
info to me no later than the following day.

Update:
The bats will tentatively be released around 2015 hrs. tomorrow April
22. IMPORTANT: the transmitters will be using CW, not FM as previously
thought. (This is completely my fault as I assumed 2m band to be FM)
Anyway, please change your mode to CW. I’m hopeful that we will get
some “hits”, especially from the folks to the South. Ashley Meyer,
the DEC representative, has agreed to do a debrief/presentation on
Monday, May 5 at 1915 hrs. I will be sending out a Zoom link a few days
prior.

Thank you all for your interest in this project.

‘73
Mark KD2RJP

All the DEC is looking for is your location when a signal is heard; and
the serial number of the transmitter. Send any reports to Mark at
kd2rjp(at)arrl.net

Vry 73 de
John
K2QY

The Great ATS Radio Challenge

By Jock Elliott, KB2GOM

Here is an idea thought up by a radio pal of mine, Andy, W2SRA.

It’s an exercise to get us operating our portable mutliband radios from manufacturers such as Grundig, Sony, XHDATA, Tecsun, Sangean, and so on. If you own a digital multiband radio that has an ‘ATS’ search function, that being a function where the radio will scan the selected band and store stations to memory automatically, this challenge is designed to see what your radio can hear from your location.

Here’s your task: During daylight hours (preferably around midday or as close it to as possible) we would like you to scan the AM broadcast band, the FM broadcast band, and the shortwave band, and record how many stations your radio finds and stores to memory for each band.

Rules:

  • No external antennas! No loops. No anything.
  • For FM & SW, the whip antenna will be fully extended, and fixed vertically.
  • For AM –you will use the internal ferrite rod antenna, and do two scans. One with the radio facing  East-West, and one facing North-South. Duplicated stations between the two scans will count as one station. (i.e. 660 is received in both directions, that will count as one station reception. 770 is received in one direction but not the other, that is one station reception.)
  • Radios that use the telescopic whip antenna for AM reception will follow the same rule for FM & SW, fully extended vertically.
  • You must do this challenge from your residence! Indoors or outdoors is your preference, but it must be with 100 feet of your residence.

This is not a contest, no prizes will be awarded. This is an experiment to see how many strong signals are received in different locations around the region. You may use any radio of your choice so long as it meets the above criteria.

For even more fun, try it at roughly the same time in the same location with two or more different radios that have ATS capability. Do not, however, combine the scores from the different radios.

Report your results in the comments below.

Initial Impressions of the Tecsun S-2200X

By Jock Elliott, KB2GOM

Bob Colegrove inspired this, with his excellent post “Pressing Buttons. Twirling Knobs and Throwing Switches.” If you haven’t read it, go do so now.

And it was our Maximum Leader, Thomas, who some time ago was asked “What’s the best shortwave radio?” His response (if I recall correctly): “The one you enjoy using.” That’s worth taking to heart. It doesn’t matter if you have the highest, techiest, super zoot receiver or SDR with the best lab numbers, if you don’t enjoy using it, how much will you really use it?

Given my age and my radio experience, my belief is that a real radio has a knob or button or switch for just about every function and a real tuning knob that doesn’t snap, crackle or pop as it changes between tuning increments.

The photos show the Tecsun S-2200X is studded with knobs and buttons, enough to satisfy an old retrocrank, but how would it perform? Dan Robinson had already reviewed it here. I respect his reviews, but I had to see for myself. With some trepidation I ordered the Tecsun S-2200X.

It arrived a couple of days ago. First impression: it’s a large radio – measuring approx. 15 inches wide, 7 inches tall, and 5 inches deep. It can run off 4 D batteries or 2 18650 rechargeable batteries, so technically it is a portable, but you’ll probably want something like a gym bag or backpack to transport it.

The fit and finish are pleasing, what you would expect from a radio in this price range. The front panel is studded with (if I am counting correctly) 33 buttons for activating various functions, 7 knurled metal knobs, a lighted analog signal strength meter, and a 3.5 inch by 1.5 inch (approx..) lighted liquid crystal display that serves as information central for the S-2200X.

On the right side are two BNC antenna connectors (one for FM and airband, the other for shortwave), a pair of clips for attaching a shortwave wire antenna, and a switch for selecting between internal and external antennas.

On the back are two hatches for installing batteries and inside one of the hatches, a switch for choosing between powering the receiver with D cells or the 18650 batteries. Also on the back, stereo line-out sockets.

On top, there are a retractable carry handle, a rotatable LW/MW antenna with a connector on the backside for an external LW/MW antenna, and a pull-up telescoping whip antenna for SW, FM, and air band.

On the left side is a port for plugging in the charging cable for the 18650 batteries.

Ease of Use

The S-2200X is straightforward to operate for basic operations (Memory operations will require consulting the well-written manual). On either side of the tuning knob are buttons for selecting FM, MW/LW, SW and Air bands, as well as selecting memory pages. Prolonged pressing of certain band buttons will activate Auto Tuning Storage of frequencies in that band, and these buttons are clearly labeled.

For shortwave, there are two buttons: SW+ and SW-, and, if you are in AM mode, these are used for incrementing between shortwave bands. However, if you are in either upper or lower sideband mode, these buttons will increment between amateur radio HF bands.

Below, and to the right of the tuning knob is a small button for switching between memory mode and frequency mode. A long press of this button will activate scanning of whatever band or memory page is active. To the lower left of the tuning knob is a button for changing tuning steps.

Below the signal strength meter is a 12-button keypad, and to the left of this are buttons for selecting synchronous detection, USB, LSB, and bandwidths. Volume and tone controls are knobs below the speaker grill.

As they used to say in the old sports car magazines: “The controls fall readily to hand.” If your goal is to pop in some batteries and start using the S-2200X right away, I found it easy to do. I particularly enjoyed the smooth tuning – both mechanical and audio – provided by the large, dimpled, tuning knob. On the unit I purchased, the tuning knob, though solidly mounted, wobbles a tiny bit.

Performance

The S-2200X acquits itself well. FM is top notch and the stereo audio is pleasing through headphones, which I routinely use to listen.

The MW performance was also satisfying, and I enjoyed using the rotatable LW/MW antenna to peak signals . . . it works! I tried plugging a Terk AM Advantage loop antenna into the jack on the backside of the rotatable antenna and found no discernable improvement in signal. To be fair, if you want the ultimate in MW DX performance, there are “hotter” MW receivers available, but I was not disappointed. I did not test LW performance.

Airband performance was average. An ATS scan of airband found five active frequencies in my area, and there is the ability to scan stored memories, stopping at each one for about five seconds.

On SW, the S-2200X delivers satisfying performance through its telescoping whip antenna. Using time stations as standards for testing, and switching between the whip and a 45-foot indoor wire loop antenna, the signal strength meter showed signals received on the whip often equaled or were only slightly less strong than those from the loop. Note well: if you conduct this experiment for yourself, there is a noticeable – perhaps one second – delay in the signal strength meter reacting to the change in antennas. If you are a SW  program listener, there are a variety of bandwidths and tone controls to fine tune the signal to your liking. I tried using the synchronous detection, and it sharpened the audio but introduced a pulsing quality to the signal that I did not like.

Most of my HF listening concentrates on single-sideband voice signals: the HF ham bands, Coast Guard weather forecasts, aeronautical voice communications, and the like. Here the S-2200X also delivers satisfying performance with impressive sensitivity on the whip antenna, a variety of bandwidths to choose from, and a fine tuning knob for dialing in the signal.

Noise Control

Now here is where the S-2200X got really interesting.

Not long ago, I became aware of a technique used by some of the experienced old hands. They would tune up on an SSB signal, then reduce the RF gain to remove as much noise as possible while preserving an intelligible signal. It made listening much more enjoyable and less fatiguing.

I tried this on my Icom IC-706 MkIIG and found that it was indeed an effective technique, but I wanted a radio I could park bedside so I could listen SSB signals on headphones while the Better Half drifts off to sleep. The Icom requires a separate power supply and an external antenna, and that seemed impractical for a bedside radio. Further, none of my portables have RF gain control.

The S-2200X does have a gain control. Here’s what the manual has to say about it: “When listening to longwave, medium wave, or shortwave, use the RF Gain control knob to adjust the gain for signals of different strengths and obtain the best reception.” I tried it on a SSB signal and it reduced the noise a little, but not nearly as much as the Icom IC-706.

Then I idly tried the squelch knob below the RF gain knob, and – tah dah! – substantial noise reduction, rendering the signal much more pleasant in my ears. The manual says: “Using the squelch control knob may reduce or suppress background noise when listening to LW, MW, SW, and airband.” As they say in the informercials: it really, really works!

Yes, but is the S-2200X really better than the other Tecsun radios that have similar basic circuitry but don’t have RF gain or squelch controls? The short answer is a definitive YES. Doing A/B comparison with my Tecsun PL-880, I found the two radios sounded about the same on a noisy band. But when I activated the RF gain and squelch controls on the S-2200X, it demonstrated a substantial advantage in “listenability” over the PL-880 with no RF gain or squelch controls.

Bottom line: based on my usage so far, I can heartily recommend the Tecsun S-2200X, particularly if you are interested in using it as a communications receiver for monitoring ham and utilities SSB signals.

Check out the Tecsun S-2200x at Anon-Co.

Qodosen DX-286 First Impressions

By Jock Elliott, KB2GOM

There was quite a bit of excitement in the ultralight radio community in 2024 when folks “discovered” the Qodosen DX-286 radio.

The very first version of this radio was the Qodosen SR-286. Its Big Trick was that it was based on the NXP TEF6686 DSP chip which is designed for car radio use and delivered impressive performance on AM (medium wave broadcast band), FM, and shortwave (it also receives LW; I have not tested that.). The SR-286 was later refined and became the DX-286, which late last year I bought. The two versions of the radio look virtually identical except for the model designation on the front panel.

The bottom line: I can, indeed, confirm the performance of the DX-286 is, as my Dad used to say, “hotter than a two-dollar pistol.”

While I don’t actually know much about the thermal properties of cheap handguns, I can say with authority that the DX-286 is very pleasing to own and operate.

The DX-286 is a small radio, measuring 5.28″L x 1.18″W x 2.99″H. The fit and finish, for the most part, are excellent. The front is studded with 23 buttons, a speaker grill/opening, and a digital display. On the left side is a port for plugging in an external antenna. On the right side, you will find a tuning knob that can be pushed in to change the tuning step and auto tuning, a volume adjustment wheel, a charging port, and a port for plugging in headphones.. On the back is a hatch for accessing the rechargeable 18650 battery and a flimsy-looking flip-out foot for propping the DX-286 at an angle. On the top of the radio is a fold-out telescoping metal antenna that measure about 19 inches long when fully extended.

The DX-286 comes in a neat foam-cushioned plastic case that includes an extensive user manual, a drawstring bag for protecting the DX-286 when it is out of the case, a charging cable and an optional extra battery.

From the DX-286 manual, here are the frequency ranges that the DX-286 can receive and the tuning steps are available.

Frequency Range/Tuning Step

FM:

  • 64-108MHz (suitable for Russia/Eastern Europe)
  • 76-95MHz (suitable for Japan),
  • 76-108MHz (suitable for School)
  • 87-108MHz (suitable for Europe, Oceania, Africa, Asia)
  • 87.5-108MHz (suitable for China, Americas)

(Tuning step is 250kHz/200kHz/100 kHz/50kHz/30kHz/10kHz)

SW: 1711-27000kHz (Tuning step is 1kHz/5kHz)

MW:

  • 522-1620kHz (Tuning step is 1kHz/9kHz)
  • 520-1710kHz (Tuning step is 1kHz/10kHz)

LW: 144-519kHz (Tuning step is 1kHz/3kHz)

Note: the DX-286 does not receive SSB signals, doesn’t do synchronous detection, or receive NOAA weather radio or the air band.

One of the things I have discovered messing with radios over the years is that ergonomics matter. The first definition of ergonomics from the American Heritage Dictionary is: The applied science of equipment design, as for the workplace, intended to maximize productivity by reducing operator fatigue and discomfort.

Let me give you an example of how ergonomics applies to radios. The XHDATA D-220 is a very simple radio. It receives FM/MW/SW bands and that’s it. As such, it has a very simple set of controls: a tuning knob, an ON/OFF/VOLUME knob, and a slide for selecting bands . . . and all that is needed.

By contrast, the Qodosen DX-286 is an extremely sophisticated receiver that offers a ton of interesting options: switching amplifiers and attenuators on and off, selecting internal and external antennas, choosing bandwidths, tuning steps and much more, each depending on what band you are trying receive.

In my view, in an ideal universe, a radio as sophisticated as the DX-286 would have a knob (or switch) for every job on its front panel, but that would make the front panel huge. However, in a small radio as sophisticated as the DX-286, many of the buttons serve more than one function, and those functions may change depending on band. As a result, you will be richly rewarded by studying the manual, which can be downloaded here [PDF], to take full advantage of the many functions of the DX-286.

But here’s the really good news: you don’t need encyclopedic knowledge of the user’s manual to use and enjoy the DX-286. I have been listening with it for three weeks and have consulted the manual exactly twice: once to find out how to switch to an external antenna while receiving MW (press and hold the RDS button) and once more to find out how to switch between medium wave and shortwave (quick-press the AM button until you get the selection you want; FM has its own button). In short, you can take a very un-sophisticated approach to the DX-286 and still have a bunch of fun with it.

The performance of the DX-286 is impressive.

I habitually listen with headphones (that helps to compensates for a hearing deficit that hearing aids can’t correct). Cruising the medium wave broadcast band, I’ve been able to hear very faint medium wave stations that I could not detect with other radios in its size class.

In addition, the DX-286 is the only ultralight that I own that allows me to connect an external antenna through a hardwire connection to boost medium wave reception. It’s easy: while in MW mode, plug the external antenna into the external antenna socket and then use the RDS button to switch from internal to external antenna. One of my joys has been to “sneak up” on very faint MW stations in the early morning using the DX-286’s internal MW antenna, then switch to the Terk AM Advantage loop antenna (connected through a hardwire) to attempt to boost the signal sufficiently to hear (or deduce) a station ID.

FM reception seems similarly robust . . . although I must admit that I am by no means an expert FM DXer.  One evening, while poking around the FM band, a faint station popped up. Wiggling the telescoping antenna around, I found that if lowered the antenna to a horizontal orientation, I could receive an entirely different FM station. Cool! The DX-286 has RDS to help in IDing FM stations, but I wasn’t using it at the time.

SW performance, in my view, is also remarkable.

One mid-morning I used the AUTO seek buttons to search for SW stations using the whip antenna and found 20. Plugging in an external 45-foot wire loop antenna and using the seek function again, the DX-286 found 38 stations, some of which were at the extreme edge of detectability.

There are a couple of additional items that deserve mention. First, it seems there is something going on with the audio/signal processing within the DX-286 that renders the audio more pleasant to listen to on a “rough copy” MW/SW signal than some of my other radios. I might be deceiving myself, but I don’t think so.

Second, the DX-286 is quiet to operate. Pushing various buttons and turning the knob results in little noise, and this preserves domestic tranquility when I’m doing my horizontal DXing with the Better Half trying to drift off to sleep next to me.

Now, if this were a trip to Santa’s Lap, improvements to the DX-286 I would like to see would include SSB operation, NOAA weather radio, the air band, and operation off ordinary AA batteries . . . but lack of those aren’t deal breakers.

In the end, I can happily use and recommend the DX-286 just as it is.

Finally, a neat anecdote involving the DX-286. One of my pals bought one in the fall. He checked into the Radio Monitoring Net, which I run Tuesday nights on a local 2 meter repeater.

“I’ve got an election story to tell you, and it involves radio,” he said.

“Like you, I watched the election results on TV Tuesday night, but with the sound off. Instead, I was using the Qodosen DX-286 to listen to results on radio direct from Atlanta and Philadelphia (he lives in upstate New York). I got the results for Georgia and Pennsylvania two hours ahead of the national news!”

I told my wife about this, and she asked, “What radio was he using?”

I bet you can figure out the rest of the story.

Click here to check out the Qodosen DX-286 at Amazon.com
(Please note: this is an affiliate link that supports the SWLing Post at no cost to you.)

A File Worth Having: Bob’s guide to building an Electrically Small Resonant Loop Antenna for Mediumwave Reception

Screenshot

This post is short and sweet.

If you click here–Electrically Small Resonant Loop Antenna for Mediumwave Reception (PDF)–you can download a copy of Bob Colegrove’s excellent paper on the Electrically Small Resonant Loop Antenna for Mediumwave Reception.

He has actually built this antenna; it works; and he uses it often. Perhaps you might want to build one for yourself. As an added bonus, Bob is an excellent writer (in my not-so-humble opinion). What’s not to like?

— Jock Elliott, KB2GOM

The Great Gonzo Radio Experiment

By Jock Elliott, KB2GOM

It’s funny how you can start out thinking about how to solve a problem, the whole process takes a turn, and you wind up with an unexpected but pleasing result.

It all started innocently enough. Alan posted this — https://swling.com/blog/2024/11/bbc-rd-how-to-test-a-loop-antenna/ — and this statement appeared at the end of a BBC report on how to test loop antennas:

“Polarisation Illustrations of the antenna usually show it mounted upright; that is, with
its axis parallel to the ground. This is fine for the reception of LF and MF transmissions, which are vertically polarised, but most HF transmissions are horizontally polarised.”

When I tested that assertion here — https://swling.com/blog/2024/12/here-we-go-loop-de-loop-in-which-your-humble-correspondent-tests-a-hypothesis/ — there were a couple of interesting responses.

Bob Colegrove said (in part):

“To address your conundrum, from my long-standing, untutored tinkering with loop antennas, I have concluded that, regardless of LW, MW, or SW, optimum performance for peaks and nulls requires that the axis of the loop (i.e., line through the center of the coil) be able to rotate 360 degrees laterally and 90 degrees vertically.” (emphasis mine)

Robert Gulley added:

“I will have to concur with Bob – if I may state it another way, there is no “proper” position for a loop when getting shortwave signals.”

To which I responded:

“I suppose the ultimate setup might be an articulated motorized outdoor mount with a joystick inside that would allow me to fiddle the loop to the optimal position.”

Early in the morning I awoke thinking about how a system capable of manipulating my three-foot-diameter MFJ 1886 loop both vertically and horizontally might be implemented. Everything that came to mind seemed awkward, hard to put together, difficult to operate, expensive, and just plain clunky.

I dozed off and woke up thinking: “What about a really small loop? I could hold it in my hand and easily turn it to different positions to optimize reception, no equipment required.”

A thought came to mind: “You’ve got a small loop antenna, why don’t you see what you can do with it?”

At this point, I need to make my Shameful Admission: I got so intrigued by the idea of using my wrist and hand to turn a small loop to various orientations that I forgot that I was trying to solve the problem of manipulating a shortwave loop.

The loop that came to mind is the Terk AM Advantage. I tested it here.  Designed to boost signals on medium wave, it is a nine-inch tunable loop encased in plastic that requires no power supply. It inductively couples with the ferrite antenna inside a portable radio. But I seemed to recall that it also comes with a direct wire connector that can be used with some radios. Perhaps I could connect it to my CCrane EP-PRO which has clips and a switch for an external medium wave antenna on the back of the case.

I found the Terk AM Advantage easily enough, but the direct wire connector required a major archeological dig. Once I unearthed it, I plugged the connector into the back of the Terk AM Advantage, slipped the wires from the connector into the clips on the back of the EP-PRO.

Now to try it out . . .

Tuning slowly down the dial, I found across a very faint signal that I could barely copy. Reaching around the back of the EP-PRO, I switched from the EP-PRO’s internal antenna to the Terk AM Advantage external loop antenna (which I was holding in my hand), rotated it from side to side, tipped it back and forth, and – tah-dah! – was rewarded by a far more copyable signal. It was WEEU in Reading PA, 200 miles away, transmitting 6,000 watts into the darkness on 830 kHz. Switching back to the EP-PRO’s internal antenna, I tried rotating the EP-PRO to optimize the signal but could not produce a signal that was as good as the external loop.

Repeating the procedure with additional faint stations, I got the same results: better reception with the handheld loop antenna, and it was fun and easy to use. I held it in my left hand (it’s light) so I could rotate the dial that peaks the signal with my thumb and working the tuning knob on the EP-PRO with my right hand. It was a very pleasing, almost addictive, experience.

If you’re looking for a potent setup for medium wave DXing, I can recommend the EP-PRO/Terk AM Advantage combo, even though it wasn’t my original objective. Call it serendipity.

In the meantime, does anyone know what might be the smallest loop that could be handheld for shortwave reception and would provide a performance boost over a whip antenna?

Here we go loop de loop . . . in which your humble correspondent tests a hypothesis

By Jock Elliott, KB2GOM

It was this post by Alan — https://swling.com/blog/2024/11/bbc-rd-how-to-test-a-loop-antenna/ — that set me off. After downloading the BBC report on how to test a loop antenna, I noticed the following in it:

“Polarisation Illustrations of the antenna usually show it mounted upright; that is, with
its axis parallel to the ground. This is fine for the reception of LF and MF transmissions, which
are vertically polarised, but most HF transmissions are horizontally polarised.”

Huh, I thought, “I wonder this would have any bearing on how I use my MFJ 1886 loop antenna?

So hooking the 1886 loop to an SDRplay RSPdx, here’s what the spectrum looks like on medium wave in vertical orientation with the 1886’s internal amp turned on:

And here’s what the medium wave spectrum looks like with the loop in horizontal orientation, amp on:

But what about shortwave reception? Here’s 31 meters in vertical orientation:

And here’s 31 meters with the loop in horizontal orientation:

Here’s 25 meters in vertical orientation:

Here’s 25 meters in horizontal orientation:

It looks to me, at the very least, the noise floor is lower . . . or I am in desperate need of a laxative?

For more about my adventures with the 1886 loop, check this — https://swling.com/blog/2022/10/testing-the-mfj-1886-receive-loop-antenna/ — and this — https://swling.com/blog/2023/01/saturday-morning-fun-fat-mw-dxing-with-the-mfj-1886/

My conclusions: I definitely don’t want the 1886 loop in horizontal orientation for medium wave DXing, but I think that the flat orientation might help for shortwave DXing.

What do you think?