MW DX Project

I don’t pay much attention to MW radio (typically called AM in the US) because FM sounds better and MW stations around here are typically full of political garbage, but perhaps I can find something of interest since I have a boatload of MW radios.

I live about 20 miles southeast of Charlottesville, VA, and I often say that it’s a weak MW signal area. My best radios get a maximum of 18 MW stations on their internal loopstick antennas, some stations too weak to be intelligible.

Loopstick antenna

I looked up the 18 stations on those frequencies and the checked their coverage maps. Three stations considered my location “local,” three “distant,” five “fringe,” one on the border line between distant and fringe, and six beyond the fringe. There are only 55 daytime MW stations total within 80 miles of me according to the FCC.

The challenge is to receive all 55.

I already know that hooking up a 20 ft. piece of wire up a tree (WUT antenna) can improve MW reception dramatically; I made a video about that, showing how I could receive a beyond fringe station with a wire up a tree and ground that an already good radio couldn’t receive on its internal antenna.

Most radios, however, don’t provide connections for an external antenna on MW, and in fact my Panasonic RF-085, Tecsun R-9700DX and Tecsun PL-330 are the only three I have do. The alternative is to wrap a few turns of wire around the radio to inductively couple the external antenna to the internal loopstick or to use what’s called a passive loop antenna that couples the same way.

Update: Testing found that several of my radios benefit on MW from clipping a long wire onto the telescopic antenna: They are:

  • jWIN MXM17
  • Kaide KK-MP903
  • Kaito WRX911
  • Degen DE28
  • Eton E1100 (aka Tecsun DR-920)
  • Panasonic RF-085
  • Prunus J-160
  • Tecsun PL-330 (antenna jack, hidden feature)
  • Tecsun R-9700DX (antenna jack)
  • XHDATA D-219

Phase one of the project is to use my current WUT antenna, and see what I can get. For that, I’ll need to pick a radio, and that process starts with determining which of my radios support external antennas on MW. Optimally, one of my good MW radios with a digital frequency display will work. The Panasonic and the Kaito are hot little MW radios with an external antenna, but it’s impossible to read the frequency accurately from their slide rule tuning display. I might not know what I’m listening to. The Tecsun PL-330 is digital, but not known for MW performance with its internal loopstick. The use of an MW/LW antenna on the PL-330 is a “hidden feature” activated by a “secret” long key press. For this and more hidden features, check out this article at SWLing Post

I thought I would try something else first, hooking up the Tecsun PL-330 to an outdoor MLA-30+ magnetic loop antenna. I did an ETM+ scan of MW and got 12 stations. That’s the same result that I get with the internal antenna. It was worth a try, but I can put that idea aside.

None of the rest of my of the digital radios listed improved with the connection of an antenna; however, I went outside at 2:45 PM local time and ran a band scan in ETM+ mode on the Tecsun PL-330 with my 20-foot WUT plugged into the antenna port, and got no fewer than 15 new stations on top of the 12 I had before. Then I scanned the frequencies by hand — what a surprise, I got 59 stations! That’s more than on the list I was going to try to find.

So what remains is verifying what those 59 stations are. I’ve started a Google sheet with the results, and will be updating that as I progress. What I know is that some of them are outside the 80-mile range I originally set up.

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Arguing with a machine: ChatGPT and me

I write about radios a lot, and use the abbreviation MHz and kHz with frequencies, but I’ve always wondered why one is capitalized and the other is not. I asked ChatGPT:

Why is the first letter of the abbreviation MHz usually capitalized, but the first letter of kHz is not?

ChatGPT replied:

The reason for this difference in capitalization between “MHz” and “kHz” has to do with the SI (International System of Units) rules for unit symbols.

In the SI system, unit symbols are always written in lowercase letters, except when the symbol is derived from a proper noun. In the case of “MHz”, the unit is derived from “megahertz”, which is a combination of the metric prefix “mega-” and the unit “hertz”. Since “mega-” is a proper prefix derived from a Greek word meaning “great”, the first letter of the symbol “MHz” is capitalized to indicate this derivation from a proper noun.

On the other hand, “kHz” is derived from “kilohertz”, which is also a combination of the metric prefix “kilo-” and the unit “hertz”. However, “kilo-” is not a proper prefix in the same way that “mega-” is, so the symbol “kHz” does not capitalize the first letter.

It’s worth noting that while these rules are widely followed, there may be variations or exceptions depending on the specific context or style guide being used.

I didn’t quite follow the rationale, so I asked a follow-up question:

So why is “kilo-” not a proper prefix, but “mega-‘” is?

ChatGPT was happy to get into the weeds on this:

The reason “mega-” is considered a proper prefix, while “kilo-” is not, has to do with their origins and usage.

The prefix “kilo-” comes from the Greek word “khilioi,” which means “thousand”. It has been used in the metric system since its inception in the 18th century and is used to represent a factor of 1000. While “kilo-” is a commonly used prefix, it is not considered a proper prefix because it is not used exclusively within the SI system. For example, the prefix “kilo-” is also used in computer science to represent a factor of 1024, which is not part of the SI system.

On the other hand, “mega-” is derived from the Greek word “megas,” which means “great” or “large”. It is used in the metric system to represent a factor of one million and is exclusively used within the SI system. Therefore, “mega-” is considered a proper prefix because it is only used in the context of the SI system.

In summary, while “kilo-” is a commonly used prefix, it is not considered a proper prefix because it is used in contexts outside of the SI system. “Mega-“, on the other hand, is exclusively used within the SI system and is considered a proper prefix.

I wasn’t having any of that. I wrote:

That doesn’t make sense. “Mega-” is used in computer science the same way “kilo-” is.

ChatGPT responded:

You are correct that the prefix “mega-” is commonly used in computer science to represent a factor of 1,048,576, which is equal to 2^20 (i.e., 2 to the power of 20). This is sometimes called a “binary megabyte” or “mebibyte,” and it is used to represent the amount of computer memory or storage capacity.

However, it’s important to note that the use of “mega-” in computer science in this way is not part of the SI system of units. The SI system officially defines “mega-” as representing a factor of 1,000,000, and this definition is used consistently across all fields that use the SI system, such as physics and engineering.

To avoid confusion between the SI definition of “mega-” and its use in computer science, the International Electrotechnical Commission (IEC) established a separate set of binary prefixes for use in computer science, including “mebi-” to represent a factor of 2^20. These binary prefixes are not part of the SI system, but they are used in many technical contexts in computer science and related fields.

So to summarize, while “mega-” is used in computer science to represent a factor of 2^20, this usage is not part of the SI system and is not considered a proper use of the prefix within the SI system. The SI definition of “mega-” represents a factor of 1,000,000, and this definition is used consistently across all fields that use the SI system.

ChatGPT can be asked to regenerate a response. I wasn’t satisfied, so here is the regenerated response:

You are correct that “mega-” is used in computer science to represent a factor of 1,048,576 (2^20), which is not a multiple of 1,000, and is different from its use in the SI system, where it represents a factor of 1,000,000 (10^6).

In the context of computer science, the prefixes “kilo-“, “mega-“, “giga-“, and so on, are used to represent powers of 2 rather than powers of 10. This is because computers work in binary, which is a base-2 system, rather than decimal, which is a base-10 system. Therefore, in computer science, 1 kilobyte is equal to 2^10 bytes, or 1,024 bytes, rather than 1,000 bytes.

In general, while the prefixes “kilo-” and “mega-” are used in both the SI system and in computer science, their meaning and usage can differ depending on the context. However, regardless of context, the rule for capitalization of prefixes in SI units remains the same: only proper prefixes derived from proper nouns are capitalized in unit symbols, and other prefixes are not capitalized.

I think ChatGPT veering into computer science was a red herring, and adds nothing to the explanation. It’s irrelevant, misleading and confusing. The key point is how the prefix can be part of a proper noun. One would probably capitalize “Great Caesar” as a title, but they wouldn’t capitalize “one thousand Caesars.” The number 1024 for computer memory and 1000 for SI units has nothing to do with the distinction.

Nevertheless, ChatGPT plus human reflection did result in an answer.

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My favorite shortwave radio

My very first website had this heading:

Find out who I am by reading my web site
and I will find out who I am by writing it.

I’m writing this article to help myself answer the question of which is my favorite radio.

I have 37 radios right now. Some are super cheap (under $10), some I couldn’t give away on eBay, some are novelties, and a few are serious radios. The candidates for favorite shortwave radio come from the last category, and they are:

  • Eton Elite Executive
  • Sangean ATS-405
  • Tecsun PL-330
  • Tecsun PL-660
  • XHDATA D-109
  • XHDATA D-808

Eton Elite Executive

An easier question is which is the best performing radio. That’s the Eton Elite Executive. It’s also the most expensive to buy (except I got it on a blowout sale under $80). It not only performs well, but it is also feature rich, including MW/FM/SW/LW/AIR, plus SSB and FM RDS. It has a convenient “scan for next station” function.

What I don’t like about this radio is that it falls over easily, and that the case is awkward to remove because of the antenna placement. I also don’t like its station memory system. It’s automatic key lockout is also extra trouble. Auto tune storage (ATS) only works on FM.

Eton Elite Executive radio (Amazon product photo).

Sangean ATS-405

The Sangean ATS-405 is a radio that I keep coming back to. It has a wonderfully clear display. The carrying case is efficient. It has excellent performance on MW. It has a convenient “scan for next station” function. It has controls for soft mute, tuning mute and squelch, but it lacks some things, like LW, Air band, SSB support, FM RDS and an external antenna jack. Also ATS is limited to MW and FM (and the number of memories per band is only 36). Shortwave sensitivity is the lowest among the contenders.

Sangean ATS-405 (Amazon product photo)

Tecsun PL-330

The Tecsun PL-330 is my go-to travel radio because it’s very compact and lightweight. It performs well. It has the best memory system of any radio I know of. It’s enhanced tuning mode (ETM+) scans the shortwave bands by time of day (1-hour groups). I easily remember how it works. It also has an ATS memory scan (that I don’t remember). The total number of memories is not documented. The manual says there are 850 ATS memories, and with ETM+ I think the total is 9,650.

What I don’t like is that it’s hard to keep track of whether you’re viewing by frequency or viewing by memory location. Also the direct entry of frequencies doesn’t always work for me (small buttons) and I have to repeat it. It also lacks a kickstand. MW performance is the poorest in the group (probably because the radio is small with the internal loopstick antenna); however, it’s fantastic with a long wire antenna (connecting an external MW antenna to the antenna jack is a “hidden feature”). I reviewed it, alongside the PL-660.

Tecsun PL-330 (Amazon product photo)

Tecsun PL-660

The Tecsun PL-660 is my oldest serious radio. It’s also my most expensive radio, $109 when I bought it back in 2011. It’s feature rich, lacking only FM RDS. It has good performance as a receiver. Its ATS works on all the bands. It is second from the top in the number of station memories, and has a good memory management system.

There isn’t much in the way of negatives, except that the radio is heavy and bulky (like the Eton). I don’t think this radio is readily available new, replaced by the PL-680. I reviewed it, alongside the PL-330, and replaced again by by the PL-880, and now the PL-990 at more than double the price.

Tecsun PL-660 (Amazon product photo)


The XHDATA D-109 is the newest radio in the group, introduced only last month (February, 2023). It is also the the least expensive, only $38.13 on sale including shipping. I ordered mine just 2 days after release and it was recalled due to defective direct frequency entry. They say they will send me a new one (it’s in transit). This radio is generating a lot of buzz in the shortwave community because it works well and has a low price.

I like the radio. I think its controls are logical. The memory system works OK, and I like the ability to scan for the next available station.

The biggest negative is that even though it has an external antenna jack, it overloads easily if you use it and there is no Local/DX switch. I have a separate review of this radio.

XHDATA D-109 (XHDATA product photo)


And finally, there is the XHDATA D-808, my most recent acquisition. It is well regarded in the shortwave listening community. It performs well and is feature rich, with MW / FM / SW / SW / AIR, FM RDS, and SSB.

It performs well, especially on MW.

What I don’t like is its abysmally bad memory system, and pathetic manual (both incomplete and inaccurate). I don’t like the feel of the buttons. I detail all of the negatives in a separate review.



So which is my favorite? I’m going to rule out the XHDATA D-808. Despite good performance, I just don’t like it. Likewise, I’m ruling out the Sangean ATS-405 because it’s not as sensitive as the others, doesn’t sound as good, and is the only one in the group that doesn’t have an antenna jack. The Tecsun PL-660 is a great radio, but it’s bulky and I really don’t use it that much; the sound is robust, but a little muddy. The Eton Elite Executive is a stellar performer, but it falls over and is clumsy to use with the snap-on case. It’s not my go-to radio. That leaves the Tecsun PL-330 that I like a lot, but I don’t tend to gravitate especially towards, and it’s the only one in the group without a kickstand. Also its speaker isn’t the most powerful. The XHDATA D-109 can’t be used with an external antenna well, ruling it out in many circumstances.

After having written all of this, I’ve discovered that my favorite radio must be one that I don’t have yet. 😕

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XHDATA D-808: Good performer, but could be better

The XHDATA D-808 arrived yesterday afternoon. My first impression, just fondling the radio, was good. It was solid and the materials seemed better than average quality. Mine is an updated model with USB-C charging. After some time using the radio, I was less impressed. I detail below how the radio has excellent performance as a radio, but that it’s operation and documentation are poor.

XHDATA D-808 Shortwave Radio (click to enlarge)


It appears some changes have been made since the XHDATA D-808 was initially announced in 2018. In 2021 the display back light was changed from white to amber. One upgrade is to the USB charging port, changing from USB Micro to USB-C. Other users have experienced the antenna coming loose from the circuit board which apparently was the only anchor point for the antenna. Now there is a screw through the back of the case that holds the antenna more securely.


I compared the XHDATA D-808 to my other $70+ radios: Tecsun PL-660, Tecsun PL-330, Sangean ATS-405, and Eton Executive Elite. Every one of them had the volume control on the lower right side of the radio except the XHDATA that has a fine tuning control there: drives me nuts trying to compare radios by turning down the volume on one and up on the other.

Several of the buttons have secondary functions. They are labeled in orange against a gray background, and as such are nearly impossible to read except in bright light (the photo above was taken in full sun, angled to make the orange letters stand out).

Keys in non-optimal lighting (on my desk with desk lamp)

The buttons are barely raised beyond the surface of the radio, and operating the radio by touch is difficult.

There is a way to set the display temperature scale, but there is no secondary label on the key that does it (it’s long press “3” with the radio off), and unless you have the display set to show temperature, there is no visual feedback that you have changed the setting when pressing the key.

The radio has 500 memories (I presume 100 each for MW, SW, LW, FM and Air — the manual doesn’t say). Having the stored frequencies divided among 10 pages, 10 frequencies each (you have to figure that out on your own), makes access clumsy and as far as I could tell, there’s no way scroll through the memories, nor any way to tell how many memories are in use. If there’s a way to delete a station from memory, I didn’t find it in the manual or online. The manual does say that the AM bandwidth or FM stereo setting is saved along with the station. There’s also nothing in the manual about retrieving a station from memory, nor are memory pages and the Page button described. The number keys on the radio default to retrieving memories, not entering frequencies — something I consider backwards.

Setting the time is tricky if you want to start the time on the second. A long press of the Set Time button starts the process, but if you don’t hit a key within 4 seconds, it exits time mode. You have to plan nearly to the second when you will key in the number so as to be able to finish at the right time. They manual says that the time will flash until the entry is completed, but in fact it will stop flashing in 4 seconds if no key is pressed. By the way, the display identifies the clock as “Timer.”

I found the antenna quite stiff to extend. Lubrication did not help. In earlier versions of the radio, this contributed to antenna failure.

I don’t like how the power switch works. When you turn the radio on, you can’t just turn it back off, because pressing the power switch activates the sleep timer. You have to wait 5 seconds before the switch will turn the radio off.

There is no tone control, nor a Local/DX switch. The display is smaller than I would prefer. I want the frequency to be front and center on the display, but it’s no larger than other information and it’s not in the center. I do like that both the frequency and the time can be on the display at the same time (the Sangean can’t do that).


The manual is awful, both incomplete and just plain wrong. Let’s say you want to direct enter a frequency like 7850 kHz or 89.7 MHz. The manual says to press the FREQ key and then the numbers, but for these frequencies the FREQ key has to be pressed again at the end. Who knew? It needn’t be pressed again for MW stations.

The radio has automatic scan and frequency storage (ATS) on each band. The manual mentions ATS, which it explains is “automatic tuning system,” says nothing about what ATS is or how it works. They just say that long presses of the band buttons are for ATS. There’s nothing about storing anything in memory, the memory page system, or how to retrieve a station from memory. Here are my instructions for saving and recalling stations from memory:

There are 100 memories for each band. Memories are organized in 10 memory pages, with 10 memory slots on each page. Select the desired band (MW, LW, FM, SW and AIR) first. Then to save or retrieve a station in memory, establish the current memory page by pressing the PAGE button and then the page number key (0-9).

Once a page is selected, a frequency is stored to a memory location within the page by long-pressing the position number (0-9). For LW, MW and SW stations, the current bandwidth is saved with the frequency. For FM stations, the Stereo setting is saved.

To recall a saved station, just press the key number (0-9) of the memory position within the current page.

The manual says the radio takes USB Micro charging, not updated to match the current version of the radio that uses USB-C. This is what it says about charging:

Charge Button
Use this radio to recharge your Lithium type batteries. Supply power to the radio from DC power adapter (not included). With the radio powered off, press and hold CHARGE button for two seconds. The battery icon on the display will begin to cycle indicating that the batteries are charging. …

The problem is that there is no button labeled “Charge” on the radio. The manual elsewhere indicates that it is the SSB button, but in any case, the radio starts charging without pressing anything.

The manual says that the external antenna jack is used by MW, SW, LW and AIR; however, testing found that it does not work with MW (and likely it doesn’t work with LW either).

There is nothing in the manual that tells the user how to tune single sideband (SSB). There is a brief description of buttons, but nothing to suggest when to press them and in what order. The manual says: “In SSB mode, rotate the fine tuning knob to adjust the level of fine tuning” but that’s true for any mode. It says nothing about using the control to clarify the signal. The manual uses the abbreviations SSB, LSB and USB, but never says what those abbreviations stand for.

The included 10-page manual‘s print is tiny, but at least the grammar is decent. I decided to write my own XHDATA D-808 User’s Manual, which is free for readers to download.


The radio performs well on shortwave; it’s comparable to the Tecsuns and the Eton — a little more sensitive on SW than the Sangean with the MLA-30+ antenna. With the whip antenna receiving WWV on 25 MHz, the Eton was, however, markedly superior to the XHDATA.

XHDATA D-808 receiving WWV on 25 MHz with whip antenna compared to other radios

I readily received some traffic on the Air band. I do like the ability to scan for the next station by long-pressing an arrow key (I wish the Tecsuns did that); however, when two stations are close together, one is likely to get skipped when restarting the scan. I like the ability to set fast/slow tuning explicitly by clicking on the tuning knob. Sound seemed good from the 1W speaker, but I need to do more comparisons.

I did a brief test of SSB. It seemed to work well and was comparable to the other DSP radios with SSB. I would rather that it worked like the Eton Elite Executive and the Tecsun PL-330 that use a single control for fast, slow and fine tuning, rather than a separate knob where the volume control ought to be.

MW performance was outstanding during the daytime with the internal antenna. I had previously done a detailed MW comparison between my Tecsun PL-330, PL-660, R-9700DX, Eton Elite Executive and Sangean ATS-405. The Sangean was the winner on MW. I went out to the same location again at midday and checked the D-808 side by side with the ATS-405. Performance was identical, receiving the same stations. On weak, barely audible stations, they both sounded exactly the same. The D-808 has the better than usual sensitivity specification of 0.5 mV/m. Typically one sees 1 mV.

FM reception is very good. I received 64 daytime FM stations on the D-808, second only to my Eton Elite Executive at 67. However, the radio only recorded 39 in memory with an ATS scan. Very strong stations tend to bleed over into adjacent channels, sometimes even two channels. The radio is supposed to be capable of setting the clock from RDS, but no station in my area includes the time, and the radio says “NO DATE” in the RDS display.


The package includes the radio, earbuds, an rolled up external wire antenna, a bag (I would have prefered a pouch with a flap), 2000 mAh 18650 rechargeable battery, USB-C charging cable and manual. The antenna is 25.5″ long.

Frequency coverage:

  • FM 87.5 – 108 (64 – 108) MHz
  • MW 522 – 1620 kHz (9k step) 520 – 1710 kHz (10k step)
  • SW 1711 – 29999 kHz
  • LW 150 – 450 kHz
  • AIR 118 – 137 MHz

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Radio of the week: Sangean ATS-405

I like the Sangean ATS-405, and my opinion of it has grown over time.

Sangean ATS-405 ( product photo)

It’s an older model (it came out in 2015), but I picked it because it has some options not usually found on other radios: the ability to set the squelch level and options for tuning mute and soft mute. These have proven unimportant, but other features have come to the front. It also has an automatic gain control (AGC) setting, an advanced feature valuable in receiving some signals that are rapidly changing in strength.


One strong feature of the ATS-405 is the display. It is bright and easy to read in the dark (with the display light) as well as in full sun. A setting allows the display light to be always on, off or delayed off (10 or 20 seconds). There is also a dedicated light switch on the top of the radio. The information on the display is just what you need, and in particular it tells you the setting of the Local/DX switch (so you don’t accidentally have it set to Local). The bandwidth setting is there along with the signal strength. A quick button press switches to the clock display.

At first I was concerned that the radio had no tuning wheel, only up and down buttons. I’ve reversed my opinion. Radios like this use a digital signal processing (DSP) chip that tune only discrete channels. A tuning knob can be tricky to use with DSP radios, sometimes skipping a channel or not advancing; however, with a button press you’re always assured you’ve incremented one channel. A long-press of one of the buttons tells the radio to scan for the next available station. The radio also has a fine tuning setting, allowing increments of 1 kHz rather than the usual 10 kHz spacing. Advanced users may use direct frequency entry rather than band scanning anyway.

I’ve compared shortwave sensitivity with some of my other radios: Eton Elite Executive, Tecsun PL-660 and Tecsun PL-330. The Sangean is somewhat less sensitive, but not bad. It’s the best of the lot on MW.

Coverage is from 520-1710 MW, 2.3 to 26.1 mHz SW, and 87.5 – 108 mHz FM. A button can step through the 14 international shortwave bands.

Other positives: Included AC adapter/charger, included case, two alarms (one buzzer and one radio), a kickstand, audio tone switch (news, normal, music) and dedicated display light button (top of radio). Unlike many modern shortwave radios, the ATS-405 manual is well-written, informative and in good English. It uses and can recharge 4 AA batteries.


My unit had a small defect: the BAND button is erratic, sometimes requiring multiple or extra firm presses.

The audio quality is not the best among my similar-sized portables. The Automatic Tuning Storage of stations in memory is only available for FM and MW, and not for SW, and there are only 36 memory locations for each band. In many locations, one would run out of FM memory locations long before reaching the end of the band. Direct entry of a frequency requires two extra button presses in addition to the digits. It does not have an external antenna jack.

My unit and apparently others have a birdie (internal interference) on 800 kHz and 1600 kHz, so I cannot listen to one local MW radio station at 800 kHz.

The elephant in the room is the lack of single sideband (SSB) reception, making it useless for listening to Amateur Radio, utility broadcasts, and other non-broadcast radio services. It’s a radio for local and international broadcast listening.


If I wanted to spend $80 on a radio today, I might look at something like the XHDATA D-808 (reviewed here) or the Tecsun PL-330. Both are more modern radios and both have SSB. The PL-330 has an excellent Enhanced Tuning Mode (ETM+) to scan and store stations by time of day. The D-808 has RDS and Air band, plus a louder speaker, but it’s memory system is awful. If I were trying to match features, I’d be more inclined towards something like the Radiwow/Sihuadon R-108 in the $50 range, or even the XHDATA D-109.


If you want in interesting radio, a stellar performer on MW, and a radio that’s easy on the eyes, then you might consider the Sangean ATS-405. I’m glad I have one.

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Mesqool CR2015 — a radio you perhaps have not seen

I bought my Mesqool CR2015 (or CR2015WB) from Amazon back in April of 2022 as part of a bundle with a larger weather radio. In the bundle, it only cost $9.11, so what the heck? The radio is no longer available on Amazon.

While it has some limitations, it’s not junk, and today I want to talk a little about it.

Mesqool CR2015WB (Amazon product photo)

It’s an MW/FM/SW/Weather band radio with weather alerts. It has a belt clip, an earphone jack, a sleep timer and an 8-page instruction sheet. Shortwave coverage is 2.3 – 23 mHz, MW is 520-1710 kHz (10 kHz step) and FM is 87.5 – 108 MHz. It runs on 3 AAA batteries, with no external power supply provision. It has a key lock switch and an emergency SOS siren with a tiny red LED flashing light. The dimensions are approximately 4.5 x 2.6 x 1 inches (116 x 68 x 26 mm). The antenna extends 11 inches. I have seen pictures of a yellow version.

The major drawback to the radio is tuning; there is no easy way to get from here to there, especially on shortwave. The operator changes frequency by way of an up or down button. A long press of one of those buttons does a scan for the next active frequency and stops on it. Scanning the entire shortwave band takes 30 minutes. Ouch! If you want to go to a particular frequency, you can choose the closest direction from where you are and get there in a maximum of 15 minutes.

The radio received 3 daytime MW stations in this very weak signal area, better than some of my inexpensive radios that only get 1 station. Several get 4-5, my Tecsun PL-660 gets 12 and my vintage Panasonic RF-085 gets 20. What is unusual is that the radio appears to have the ferrite antenna aligned with the side of the radio, not the top, so to receive MW stations, the radio has to be placed on its side.

It received 31 stations on FM, lower than any other radio I have tested. Stations it did receive were clear and crisp sounding, quite listenable. I tried headphones and detected a bit more bass than from the speakers, but still not much.

The manual is one of the more literate ones I have seen from Chinese manufacturers, but it does have one big error. The manual gives instructions for setting the clock, but the radio has no clock.

The CR2015 receives one NOAA weather station in my area, the same number as every other weather radio I’ve owned. I have not tested the weather alert function.

Now, for shortwave. It’s probably not worth testing the radio in the daytime with the diminutive whip antenna — better my 20-ft. WUT antenna (wire up tree). In the daytime (around noon local time, 05:00 UTC) in central Virginia the radio got some stations, but the band scan took 30 minutes! There was some overload / breakthrough particularly on the lower frequencies, omitted from the edited video of the scan. The wind was blowing something fierce and so there is noise from that.

And here is the radio’s evening performance receiving NHK Japan on 6105 kHz indoors around 03:21 UTC using just the 11″ whip antenna.

Here is the Mesqool CR2115 User Manual.

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Tecsun R-9700DX Radio Compared

I’ve hesitated to talk about the Tecsun R-9700DX radio much because while other reviewers like it, I was disappointed, and I didn’t want to bad mouth a radio unfairly. In this article, I’ll also refer also to my vintage Panasonic RF-085 receiver that I bought around 1985.

Panasonic RF-085 radio (left) and Tecsun R-9700DX (right)

I’ve been listening to shortwave radio for a very long time, and I have owned over 100 radios. What I expected from the R-9700DX was a good example of where analog technology had reached in the 21th century. I expected to be impressed but I wasn’t.

Let’s start with sensitivity specifications. Here are the values for two radios:

BandTecsun R-9700DXPanasonic RF-085
MW< 1 mV/m200 µV/m for 50 mW Output
FM< 10 µV 3 µV for 50 mW Output
SW110 µV for 50 mW Output
SW28 µV for 50 mW Output
SW35 µV for 50 mW Output
SW< 30 µV
Radio sensitivity specifications

That doesn’t help much because the Tecsun doesn’t specify a standard, and the Panasonic uses an uncommon one. I’ll assume the Tecsun is using S / N = 26dB, something quoted by Tecsun for other radios, and if so, the R-9700DX lags behind Tecsun’s DSP-based radios like the PL-330 and its digital display analog radios like the PL-660, both with 20 µV on SW and 3 µV on FM. MW is the same 1 mV. My personal observation is that the R-9700DX isn’t particularly sensitive. I get 7 MW daytime stations (weak signal area) on the R-9700DX, 12 on my Tecsun PL-660 and 20 on the Panasonic (that blows everything else away on MW). I mistakenly thought that a big heavy radio would have a big ferrite antenna and have good MW reception, but it really doesn’t. Shortwave performance was mediocre too.

Tuning range is a consideration. The Panasonic tunes from 2.3 to 18 mHz in 3 contiguous bands. The Tecsun covers 3,9 to 21.85 mHz in 10 non-contiguous bands; while the tuning range is larger, there are gaps between the bands on the Tecsun, so it’s a bummer that it can’t receive WWV on 10 and 15 mHz or CHU on 3330, 7850 and 14670 kHz, while all are there on the Panasonic. And what about MW? I can excuse the Panasonic for its limited MW band given its age, but how could a modern radio not cover 1620 – 1710 kHz?

I found the R-9700DX tuning knob stiff, but without noticeable backlash.

I told myself once that I would never buy another radio with an analog dial because it’s hard to identify a station with only an approximate frequency. This radio is not only analog (and approximate) but also inaccurate. A detailed test of all the bands (using a signal generator and frequency meter) found some of the frequencies were just wrong. The video following is a booming signal on 11930 kHz from Radio Marti (pretty much the strongest daytime SW station here) around 18:15 UTC with the Tecsun’s whip antenna. You can look for yourself, but I say the dial is not accurate (SW6 band) for that frequency. The dial pointer is above (lower frequency) than the 11.9 mark.

Radio Marti on 11930 kHz – Tecsun R-9700DX

On the plus side, the Tecsun has a “big radio” sound and is pleasing to listen to for music on FM. It has a nice warm vintage dial light.It has a Local/DX switch. It comes with a power supply, case, manual (half a sheet of paper printed on both sides), earbuds and an external antenna. Both the Tecsun and the Panasonic have connectors for an external antenna and both can use it on MW.

I went outdoors in mid afternoon and hooked my 20-foot wire up a tree (WUT) antenna to the radio’s external antenna jack. I switched to SW3 (49m) and tried to find CFRX on 6070 kHz. What I got was very strong SSB transmissions all over the band. CFRX was not to be found. Figuring the radio was overloaded because those signals were not really on those frequencies, I flipped the DX switch to Local and got basically nothing but noise, no CFRX.

Then I disconnected the external antenna and tried the whip antenna alone. That got a decent signal from CFRX.

Then for one final experiment, I clipped on the long wire instead of using the antenna jack. The SSB overload was barely there and I could get CFRX.

Note: I didn’t have the overload problem (if that’s what it is) on higher-frequency bands.

For videos comparing the Tecsun R-9700DX to a bunch of other radios, check these out:

The Tecsun R-9700DX is an OK radio, but I was expecting something special. Its performance is lackluster, but I suppose reasonable for a $45 radio ($60 on Amazon). Some have suggested that the Chinese version (which I have) may not be subject to the same quality controls as the English version and perhaps uses cheaper components; this is just speculation as far as I’m concerned. Maybe I just got a bad one, but everything works, just not as well as I’d hoped. The radio was introduced 21 years ago, so who knows how many versions it has gone through in that time.

I couldn’t find a manual online, so here is a photocopied manual for the Tecsun R-9700DX, such as it is, for posterity, and for reference here’s the manual for the Panasonic RF-085.

Performance hint: the Local/DX switch applies to both the external and internal antenna.

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