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With all the fires and severe weather happening around the world, I’m curious if other communities have been doing emergency radio give-aways? I thought you or other SWLing Post readers might have seen similar stories?
73, NT
Great question, NT!
Post readers: please comment if you know of other communities around the world who’ve deployed weather radios in an effort to prepare for natural disasters.
Many thanks to SWLing Post contributor, Carlos Latuff, who writes:
Technology considered obsolete, the fax, or better, radiofax (transmitted by radio) continues to be used by several meteorological agencies around the world, which broadcast weather charts to vessels on the high seas. These two images were transmitted today by the Japan Meteorological Agency and received at 19h10 and 19h50 (UTC) in Porto Alegre, Brazil.
The first image is a photo from the Japanese satellite Himawari 8. Even with noise, due to the shortwave propagation, you can see clearly the “eye” of typhoon Surigae.
The second image is a typhoon alert, indicating on the map that Surigae has changed course and is now en route to the Pacific.
These two images were transmitted today by the Japan Meteorological Agency, on the frequency of 7795 kHz
Thank you for sharing this, Carlos. It’s amazing, the amount of information you can receive over the air even with modest equipment by today’s standards. With a modest portable radio and a little decoding software, anyone can grab images like this.
Radio Waves: Stories Making Waves in the World of Radio
Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’sRadio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!
Many thanks to SWLing Post contributors Rob (PE9PE), Bennett Kobb, Harald
(DL1AX), and Dennis Dura for the following tips:
ANATEL, the Brazilian National Telecommunications Agency, recently published a public consultation, CP65, which is available at this link:
In their website, LABRE, the Brazilian Amateur Radio League, was surprised by the CP65 proposal that proposes, among other topics, the extinction of the COER (amateur radio certificate) exam for all classes and replacement by free access to initial class C, as is done today with the Citizen’s Band, as well as access to subsequent classes B and A upon presentation of the Certificate of Technical Course and Graduation in Telecommunications, respectively, or minimum stay of 3 years in each class.
In addition, the aforementioned proposal suggests ending the rules of different prefixes for each of the States of the Federation, remaining only the prefix per class and there would no longer be any special callsigns.
The proposal, in addition to going against what is consensus in the international regulation related to the Amateur Radio Service, is absolutely contrary to the LABRE’s thinking with regard to the minimum requirements to be a radio amateur and also does not match ANATEL’s request for support from LABRE in the revision of amateur radio regulations in Brazil.
For further clarification on the subject, LABRE has already requested a meeting with ANATEL, which will be scheduled soon.
Story by Bennett Kobb:
On September 3, radio engineer Alex Pilosov of Shortwave Solutions filed with the FCC an objection to WIPE, the DRM-based HF station of Turms Tech of New York, presumed to be ready to broadcast from the Armstrong Tower in Alpine, NJ.
WIPE is suspected to be intended mainly for secret, non-broadcast message transmission for private trading clients while broadcasting financial and economic news for the public.
WIPE is not yet operational. The station is waiting on its FCC license, but Pilosov took aim at possible glitches in its license application. He also raises the issue of whether U.S. shortwave stations can legally conduct non-public telecommunications in the broadcast bands in a service limited to broadcasting.
Pilosov is a consultant to HF stations in the Experimental Radio Service, which are not constrained by the broadcast rules; thus he or his clients are prospective competitors to WIPE. This is Pilosov’s second FCC objection. He also filed against the application of Parable Broadcasting for WPBC, a DRM HF station proposed for Batavia, IL.[…]
In 2020 we celebrate the centenary of radio in Argentina. Such an event can be approached in various ways, since there are several milestones along this century of radio in our country. There are some events that are marked by fire in collective memory.
It is our intention to approach the celebration focusing on an event in which radio was in the spotlight: the 1982 Malvinas War, a conflict waged on various fields: military, economic, diplomatic and, of course, communications, mainly as a means of propaganda.
Most countries over time have recognised the great potential of radio as an effective instrument both in times of war and peace. Historically, Germany was the first country to use this for purely political purposes.
During WWII the broadcasts of Radio Tokyo, Radio Germany, the BBC in London and other stations were used for propaganda and military purposes by combatant nations.
The post-war period and the subsequent Cold War brought along a “war of the airwaves”. During these years, countless stations emerged with their own propaganda styles, looking to advance their social, political and economic systems.
An example of this are the broadcasts of Radio Moscow, Voice of America or Radio Beijing. Along with these stations, others of a clearly political nature emerged, such as Radio Free Europe and Radio Liberty, that targeted countries in Eastern Europe, as well as nations that became independent after the collapse of the Soviet Union. This group also includes the so-called clandestine stations, which generally broadcast secretly from conflict zones or from nearby regions or using rented transmission sites.
Before April 2, 1982, the Malvinas Islands had one radio station: the Falkland Islands Radio Service (FIBS) – with broadcasts in English. Content aired included locally-produced programs as well as news services of BBC London. It broadcast on 536 khz and 2370 khz.
The AM frequency was intended to cover the Port Stanley area, reaching a little further with SW transmissions.[…]
List of 48 Weatheradio Canada transmitting site proposed for decommissioning (Weatheradio Newsletter)
Many thanks to a number of SWLing Post readers who’ve recently contacted me regarding announced closures at Weatheradio Canada. Dennis Dura recently shared this link from the Weatheradio Newsletter which is essentially a call to action to save the Weatheradio service.
For those of you not familiar, Weatheradio Canada is very much like NOAA Weather Radio service in the US: essentially, a vast network of transmitters which provide local forecasts and weather warnings. Both Weatheradio Canada and NOAA Weather Radio use seven fixed frequencies of 162.400, 162.425, 162.450, 162.475, 162.500, 162.525, and 162.550 MHz.
I found it difficult to believe that Canada would close their entire network of Weatheradio FM transmitters because, like the US, there are vast rural and remote areas that are well-served by the radio network. I can’t tell you how many times I’ve been camping or travelling outside of mobile phone network coverage in the US and Canada and relied on weather radio for my forecast.
I decided to reach out to Environment and Climate Change Canada and get their official word. Here’s the response I received from their Media Relations representative:
As Canada’s official source for weather forecasts and alerts, Canadians rely on getting the latest current weather conditions from Environment and Climate Change Canada’s (ECCC) Meteorological Service. Since 1871, Canada’s Meteorological Service has continuously adapted to and taken advantage of the latest science and technology to maximize services to Canadians, including those living in remote or Northern areas, or areas without cellular service.
The Weatheradio network, introduced in the 70’s, is made up of 230 transmitting stations. For the most part, these Weatheradio transmitters are in urban areas with plenty of options for accessing weather information and alerts, e.g. internet, mobile apps, radio, television. ECCC has identified 48 Weatheradio transmitters across Canada for potential decommissioning. Of these 48, 12 in Ontario, three are in BC, three in AB, five in SK, four in MB, five in QC, five in NB, three in NS, one in PEI and seven in NL.
In other words, Environment and Climate Change Canada is considering decommissioning about 21% of their Weatheradio transmitters, targeting ones located in urban areas.
The Midland WR120 weather radio.
I haven’t seen a map of the transmitters marked for potential closure, but I strongly suspect if you live in a very rural area you’re unlikely to be affected.
If you live in an urban area, however, and routinely rely on a weather radio for forecasts and automatic alerts, you may soon only hear static.
Many thanks to SWLing Post contributor, Mike Ladd with SDRplay, who shares the following guest post:
Basics to decoding WEFAX using an RSP and SDRuno
by Mike Ladd
SDR I use: RSPduo from SDRplay using the Hi-Z input. Any model RSP’s can tune WEFAX transmissions. https://www.sdrplay.com/rspduo/
Antenna I use: Megaloop FX from Bonito. In an Inverted delta loop configuration pointed N/E-S/W. Any good antenna placed outdoors should be fine. It’s all about the SNR, not your S-meter reading. https://www.bonito.net/hamradio/en/mega-loop-fx/
Software:
SDRuno v1.32
SDRuno is an advanced Software Defined Radio application platform which is optimized for use with SDRplay’s range of Radio Spectrum Processing receivers. https://www.sdrplay.com/downloads/
VBcable (donationware) vPack43
Transfers audio, digitally from one application (SDRuno) to another (Black Cat HF weather Fax) with zero loss. https://www.vb-audio.com/Cable/
Black Cat HF Weather Fax (paid for use) beta 19
Decodes and produces images from the WEFAX transmissions from the output of SDRuno using a virtual audio cable.
Black Cat Uno UDP
UnoUDP allows you control SDRuno’s VFO frequency from within Black Cat HF Weather Fax scheduler. This is done over a virtual com port pair using a virtual com port emulator. http://blackcatsystems.com/download/UnoUDP.zip
VSPE or COM0COM
VSPE is a paid for use app. COM0COM is completely free. Either one of these applications will work. A virtual com port emulator allows you to create a virtual com port. The pair will internally link Black Cat Weather Fax decoder to SDRuno’s using UnoUDP as the transport protocol.
This document is not a definitive guide to the WEFAX protocol, the process of decoding WEFAX images or reading a synoptic weather chart https://youtu.be/kzfNSvQREu8. This is only a collection of information that I have found scatter throughout the internet and re-compiled into a document, this document. Expect typographical mistakes, inaccuracies, or omissions.
WEFAX is an analog mode for transmitting monochrome images. It was the predecessor to slow-scan television (SSTV). Prior to the advent of the commercial telephone line “fax” machine, it was known, more traditionally, by the term “radio facsimile”.
Facsimile machines were used in the 1950s to transmit weather charts across the United States via land-lines first and then internationally via HF radio. Radio transmission of weather charts provides an enormous amount of flexibility to marine and aviation users for they now have the latest weather information and forecasts at their fingertips to use in the planning of voyages.
Radio fax relies on facsimile technology where printed information is scanned line by line and encoded into an electrical signal which can then be transmitted via physical line or radio waves to remote locations. Since the amount of information transmitted per unit time is directly proportional to the bandwidth available, then the speed at which a weather chart can be transmitted will vary depending on the quality of the media used for the transmission.
Radio fax data is available from the web on sites such as the ones hosted by the National Oceanic and Atmospheric Administration (NOAA). https://tgftp.nws.noaa.gov/fax/marine.shtml Radio fax transmissions are also broadcasted by NOAA from multiple sites in the country at regular daily schedules https://www.nws.noaa.gov/os/marine/rfax.pdf. Radio weather fax transmissions are particularly useful to shipping, where there are limited facilities for accessing the Internet.
Black Cat HF Weather Fax is a program that decodes WEFAX (Weatherfax, HF-FAX, Radiofax, and Weather Facsimile) transmissions sent from fixed locations around the globe.
A fax is transmitted line by line, typically at a rate of 120 lines per minute, or half a second per line. For example, to send a weather chart, you would start in the upper left corner. You would send the value of that pixel (dot), black, white, or perhaps a shade of gray. Then you would move over one pixel to the right, and send that pixel, and so on, until you reach the edge of the chart. Then you’d move all the way back to the left edge, and move down slightly, one line, and repeat the process.
Each pixel is converted into a certain audio frequency or tone. By convention, a tone of 1500 Hz represents black, 2300 Hz represents white, and frequencies in-between represent shades of gray. So if you listen to a fax transmission, you’ll hear the different tones as each pixel is present. For example, listen to a chart with mostly white background being sent. You’ll hear mostly the high pitch 2300 Hz, and some lower (1500 Hz) blips as each black pixel is sent. When a horizontal line is sent, you’ll hear a long half second burst of 1500 Hz, since the line is all black.
The transmitting station frequency modulates the carrier. That is, when a black pixel is transmitted, the carrier shifts down 400 Hz. When a white pixel is transmitted, the carrier shifts up 400 Hz. For a medium gray pixel, it stays on the assigned frequency. This is how most fax transmissions are made. Since we’re tuning it in SSB, it sounds to us as if the station is transmitting a variable frequency audio tone. The two processes are identical. This accounts for the confusion regarding what frequency to tune the radio to in order to properly decode the fax transmission. Different stations list their frequency in different ways. It is important to remember that a black pixel produces a 1500 Hz tone, and a white pixel produces a 2300 Hz tone within the AUX SP.
The setup works as follows. SDRuno demodulates the received signal. The demodulated audio is piped from SDRuno using virtual audio cable and sends it to the HF weather fax decoder. HF weather fax decoder receives this audio from the virtual audio cable that was demodulated from SDRuno and processes it, producing a picture on the screen
HF weather fax decoder can also set the VFO (tune) frequency of the RSP in SDRuno. This is done over the virtual com port pair using the UnoUDP application as the transport.
SDRuno can internally emulate a Kenwood TS-480, UnoUDP sends the Kenwood TS-480 serial commands via UDP over the virtual com port pair in order to set the frequency selected from the HF Weather Fax Scheduler option over to SDRuno.
You will need to install and configure the following applications.
1: A virtual audio cable.
2: A virtual com port emulator (If you would like HF Weather fax to communicate with SDRuno).
3: UnoUDP (If you would like HF Weather fax to communicate with SDRuno using the virtual serial emulator).
4: HF Weather Fax.
5: A simple wire antenna placed outdoors.
Virtual Audio Cable:
A virtual audio cable allows you to pipe the audio from one application (SDRuno) into another application (a decoder like HF Weather Fax) digitally. I will assume SDRuno is already installed with your device attached and functioning properly.
You can now download a virtual audio cable package. If you already have a virtual audio cable package installed, you can skip to the next section. If you don’t have a virtual audio cable application installed, you only need to choose one and install only one of the two that are available.
Close any running apps, install the virtual audio cable and reboot your computer. When your computer boots to your desktop, your computer will now have a virtual audio cable pair installed on the system.
You can verify it the installation by going to your Control Panel and double clicking the Sound icon. VB-Cable and Virtual Audio Cable will only install a single virtual audio cable pair, one is for the input (Recording) and one is for the output (Playback). A single pair is all that is needed (as shown below).
Virtual Serial Port:
A virtual com port emulator is only needed if you would like Black Cat HF Fax decoder the ability to tune the station in SDRuno when you double click a station name in the HF Fax Decoder scheduler.
Please use the links provided (additional PDF’s and YouTube videos) on Page 2 of this document for an installation / configuration walkthrough.
Download the latest HF Weather Fax beta package and the UnoUDP application from the link provided on Page 2 of this document. I suggest making one main folder called HFfax and two subfolders within HFfax for each of the applications. One folder is for the HF Weather Fax Decoder and the other folder is for the UNO UDP transport application.
Double click the HF Weather Fax beta ZIP file you downloaded and extract the full contents of this ZIP into the folder you created on your local drive. Right click the “Black Cat Weather Fax” EXE file and send a shortcut to your Desktop.
Double click the UnoUDP zip file you downloaded and extract the full contents of this ZIP into the folder you created on your local drive. Right click the “UnoUDP” EXE file and send a shortcut to your Desktop.
You should have two shortcuts on your desktop, One for the decoder and one for the transport app.
Black Cat UnoUDP:
HF Weather Fax needs a way to communicate with SDRuno, this is done via UnoUDP and the virtual com port emulator.
Launch UnoUDP with the above configuration. Set your UDP Receive port to 58084 and your UDP send port to 58083. UnoUDP must be left running in the background, this will control SDRuno. You can minimize the application or right click the shortcut and have UnoUDP auto minizine on launch.
You should see a Firewall popup prompt asking permission to allow UnoUDP to pass data within the system. You must allow this traffic to pass or external control of SDRuno will not be possible from the HF Weather Fax decoder scheduler.
Assign 1 of the 2 com ports from the virtual com port emulator to UnoUDP (the 2nd com port will be assigned to SDRuno). My com port pair is Com 1 and Com 2, SDRuno uses Com1 and UnoUDP uses Com 2.
Black Cat HF Weather Fax:
HF Weather Fax needs to be configured in order to communicate with UnoUDP, this is done via the UDP settings. Click “Edit” and “Preferences” Set the UDP Send port to 58084 and the UDP Receive port to 58083.
You should see a Firewall popup prompt asking permission for HF Weather Fax to pass data within your system. You must allow UDP traffic to pass or external control of SDRuno will not be possible from the HF Weather Fax decoder scheduler.
SDRuno:
SDRuno needs its Output assigned to the Virtual Audio Cable. The output can be changed via the RX CONTROL panel, clicking the SETT. button on the top left and clicking the OUT tab.
SDRuno needs a com port assigned so it can be externally controlled. The serial port is assigned via the RX CONTROL panel, clicking the SETT. button on the top left and clicking the CAT tab.
I recommend running the RSP in LOW-IF mode, this is selected via the MAIN panel. This reduces the need to track separation between the Tuned frequency and LO (local oscillator) https://youtu.be/Fsns4P3JxrM
LOW-IF mode also minizines the LO being placed outside of the desired preselect filter of the device in use, Remember the preselect filter is automatically enabled based on the LO frequency https://youtu.be/w-vkiVp7Q4E
I also recommend leaving the IF AGC enabled and placing the RF GAIN as high as possible without causing an ADC OVERLOAD warning within the MAIN panel. If an ADC OVERLOAD warning appears, back the RF GAIN down.
Launch SDRuno. Set the mode to USB and the filter width to 2.8k
HF weather fax will not set the mode or filter width at this time.
Click the Sked button in Black Systems HF Weather Fax. A current WEFAX transmission schedule will appear. Stations listed in White are either scheduled to transmit or about to transmit based on your computers clock. Stations show in Grey at the bottom of the list are currently off the air or not transmitting.
In the Freq Offset: box enter -1.9 and hit enter (Reason for this is on Page 5).
Click any of the stations listed in the Fax Transmission Schedule and it will automatically tune SDRuno to the correct frequency.
Black Cat HF Weather Fax folder will have a file named “Black Cat HF Weather Fax Docs” Please view this file to understand some of the advanced features available.
Your first decode (Without UnoUDP)
Launch Black Cat HF Weather FAX.
Launch SDRuno.
Navigate to the Memory Panel (MAIN panel and click the MEM PAN button)
Right click the Memory panel and select “Open bank”. Navigate you C drive telling SDRuno the location of WEFAX.s1b
Double click any of the frequencies shown within the WEFAX bank and SDRuno will set the correct mode and tune that station. My WEFAX.s1b file defaults to the Hi-Z port. If your device lacks a HI-Z input, navigate to the port section within the memory panel, double click the stations port you want to edit and change it to the correct port that’s available or in use for your device. Right click the memory panel and “Save bank” to save the changes.
To use my SDRuno WEFAX frequency bank properly. The MCTR button must be enabled within the RX CONTROL panel, enabling this option allows you to double click and tune a station that is stored within the WEFAX bank. Make sure the LO is not locked in the MAIN panel (LO LOCK).
If a decoded WEFAX image looks blocky or skewed or possibly pixeled, I recommend that the lock output fractional resampler option is enabled in SDRuno. You can enable this from the RX CONTROL panel, clicking the SETT. button on the top left and clicking the OUT tab.
I hope this document helped guide you in getting started with decoding WEFAX transmissions from around the world. I am sure I missed some key features, remember this is only a primer/basics to decoding WEFAX. I do have an accompanying video located here
SDRPlay modules use a Mirics chipset and software. The information supplied hereunder is provided to you by SDRPlay under license from Mirics. Mirics hereby grants you a perpetual, worldwide, royalty free license to use the information herein for the purpose of designing software that utilizes SDRPlay modules, under the following conditions:
There are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document. Mirics reserves the right to make changes without further notice to any of its products. Mirics makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Mirics assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters that may be provided in Mirics data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters must be validated for each customer application by the buyer’s technical experts. SDRPlay and Mirics products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Mirics product could create a situation where personal injury or death may occur. Should Buyer purchase or use SDRPlay or Mirics products for any such unintended or unauthorized application, Buyer shall indemnify and hold both SDRPlay and Mirics and their officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that either SDRPlay or Mirics were negligent regarding the design or manufacture of the part. Mirics FlexiRFTM, Mirics FlexiTVTM and MiricsTM are trademarks of Mirics .
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Two months ago, SWLing Post reader Paul Adler wrote to ask:
“Any reviews and comparisons of the Sangean DT-800?”
The Sangean DT-800? This caught my attention, as I wasn’t, at the time, familiar with this recent addition to the Sangean product family. So I promptly began investigating the new product, and checked out the manual; I found it has a few features that really intrigue me, namely:
The ability to turn off soft muting
The ability to internally recharge NiMH AA batteries
Multiple bandwidth on AM and FM
Weather band with weather alerts
FM RDS
No telescoping antenna––rather, an included wire antenna
In my mind, these features seemed to set it apart from other similar portables. And with the ability to defeat the soft mute, I wondered if it could make for a formidable Ultralight DX radio?
I contacted Sangean, and they kindly sent me a review sample of the DT-800. It comes in two chassis colors: standard black and and a bright fire yellow. I chose yellow, which makes it easier to spot should this handheld be lost or dropped in an outdoor setting.
Thanks for the suggestion, Paul!
Giveaway! By the way: since this is a product sample and was sent to me free of charge, I’m going to give it away to a lucky SWLing Post Coffee Fund or Patreon supporter next week, just to say thanks!
Now, let’s get on with the review…
Initial impressions
As with almost all Sangean products, the DT-800 arrives as a complete package, with all accessories. Inside, you’ll find the radio, a full-length multi-language owner’s manual, a warranty card, an AC adapter (with in-line RF chokes, nice touch), in-ear headphones, an external wire antenna, and a belt clip.
The DT-800 fits nicely in the hand, and the matte finish on the sides and bottom of the radio make gripping it quite easy, lessening the chance of dropping or losing the unit.
The front panel is simple: five multi-function preset buttons and a Page/Menu button. All of the buttons are tactile and have a matte finish, as well; they feel of good quality and have a great response.
The right side of the radio (see side view, above) has a tuning/select up/down jog switch, a mechanical keylock button and a MicroUSB DC in port.
On the left side of the radio (see left side view, above) you’ll find the volume up/down buttons and a stereo/mono/speaker mechanical switch which you can use to switch between the internal speaker and headphones.
On top of the radio (above) you’ll find the power button, band selection button and the headphones port, which doubles as the external antenna port.
On the back of the radio you’ll find the DBB bass-boost slider switch, the battery compartment, and a belt clip.
One thing you’ll quickly notice is a lack of any telescoping whip antenna. Instead, the DT-800 ships with a wire antenna that’s almost three feet long. I suspect that this is the same type of FM antenna that shipped with the Sangean WR-7 (click here to read review).
Design/Ergonomics
All in all, I’m very pleased with the DT-800’s design: it fits well in the hand, the buttons and controls are easy to use, and it’s small enough––and flat enough––to easily slip in a pocket, go-bag, or carry-on. A great portable for one-hand operation. It’s also lightweight, even with the batteries inserted. Truly, this appears to be a quality little radio.
Tuning the DT-800 is a simple process: simply utilize the up/down rocker switch on the right side of the radio to increase by specified frequency steps (selectable 50/100 kHz FM or 1/9/10 kHz AM), or push and hold it in one direction to skip across the band. While the DT-800 does mute between frequencies, it’s not annoying––in fact, muting is brief and audio recovery is rapid so you can actually carry out meaningful band-scanning, actually hearing stations between the steps. If you press the rocker switch, it will initiate an auto-scan in the direction you’re tuning.
While the DT-800 lacks a keypad for frequency input (in truth, I would not expect such a thing on a walkman-style receiver) it does make tuning to your favorite stations quite easy with 20 FM, 20 AM, and 5 WX presets. Saving a station to memory is truly a breeze: simply select the page you’d like to save it to, then press and hold the preset button to save it to one of the numbered presets. Really, it couldn’t be easier.
To change the volume on this radio, you use rocker buttons on the left side of the radio to increase or decrease volume up to 25 levels. I particularly like the fact that level 1 is very quiet and 25 is as loud as you would ever want from a small radio. I mention this because, in the past, I have reviewed radios that had coarse volume steps, and the lowest setting is louder than I prefer: not so with this little rig.
Entering menu items on the DT-800 is quite easy, too. Some are accessed by pressing and holding the Page/Menu button and then cycling through and selecting items with the tuning up/down switch. Others are accessed by pressing and holding the Page/Menu button, then selecting one of the five buttons on the front panel (note that each menu function is listed below the numbered button).
The DT-800’s display is backlit and large, thus very easy to read at any viewing angle.
AC Adapter
I can’t think of the last time I gave an included AC adapter its own subheading in a review, but the DT-800 power supply deserves one.
Not only does the DT-800 ship with a power supply (AC adapter), but it’s a quality one: the cord jacketing is thick and feels exceptionally durable––and though I’m not going to cut it apart to find out, I expect the wiring within it is a heavier gauge, as well. This adapter also has no less than two in-line RF chokes.
In a day and age when included “wall wart” power supplies are often of the cheapest quality and spew so much radio interference that they render attached receivers useless, the DT-800 adapter is a very welcome addition to this radio’s kit.
Well played, Sangean! I hope other radio manufacturers follow your lead.
Batteries
Lately, it seems most new radios are being designed to accommodate slim Lithium Ion battery packs. So, another welcome sight was opening the DT-800’s battery compartment to find slots for two AA batteries.
While Li-ion batteries have advantages in terms of weight and size, I prefer AA batteries for pocket and travel radios, as AA batteries are so ubiquitous on this planet and are available in all but the most remote regions of the world.
And better yet? You can internally recharge NiMH batteries with the DT-800. The DT-800 ships with a default setting for alkaline batteries. But to internally recharge NiMH batteries, simply open the battery compartment and change the battery type switch from “Alkaline” to “NiMH.”
This is an amazing and useful feature, but just be sure if you ever use the NiMH internal recharging function and then switch to alkaline cells, that you change the battery selection switch back to the alkaline setting. You certainly wouldn’t want the DT-800 to attempt recharging your alkaline cells!
As you can see in this photo, I’ve been using Panasonic Eneloop NiMH batteries in the DT-800. I use a special charger for Eneloops, so have kept the battery selection switch set to alkaline so the DT-800 doesn’t attempt to charge them. I might even put a small piece of colored tape on the switch to keep it in place for now.
Audio
The audio via headphones? It sounds great on the DT-800!
Indeed, the DT-800’s included in-ear style stereo earphones are a cut above most other included-with-a-product earphones, and as a result, produce more pleasant audio.
With the headphones engaged, FM offers selectable mono or stereo; mono, of course, makes marginal stations more stable since the stereo lock isn’t struggling.
Like the Walkman radios of days gone by, the DT-800 uses the headphone cord as an antenna when it’s attached. If you’re using the internal speaker, you’ll need to attach the included external wire antenna for FM and WX bands.
The DT-800 internal speaker produces decent audio for the size of the radio. The speaker is tiny, so the audio is somewhat tinny (narrow in range) when listening to music. But the DT-800 also has a DBB (Dynamic Bass Boost) switch––engaging this will increase the bass response a bit, most noticeable when using headphones.
Performance
The DT-800 has three bands: FM, AM (mediumwave), and WX (weather). Let’s take a look at each.
FM Band
The DT-800 sports a unique feature on the FM band: the ability to select between a wide or a narrow filter. Since the dawn of the DSP chip, many a portable radio has enjoyed selectable bandwidth filters, but it’s a rare portable that has FM filters. I do pretty much all of my FM listening with the wide filter engaged, but if you live in an urban area with a crowded FM band, choosing the narrow filter, even if it compromises audio fidelity a bit, will give you better selectivity. Nice touch, Sangean!
In terms of sensitivity, with the external antenna inserted, I’ve been very pleased with the DT-800. It receives all of my benchmark FM stations. With headphones inserted (used as an antenna) and stereo engaged, it has ever-so-slightly less sensitivity than several of my other DSP portables. With the headphones inserted and FM in mono, I find that it’s on par with––or surpasses––my other reference DSP portables.
Here’s a little wrinkle, though: when listening with the internal speaker, you must insert the external wire antenna to use this receiver on FM. Without the external antenna, sensitivity decreases by a good 70-80%, as you essentially have no antenna. If you live in an area with strong FM stations, you’ve nothing to fear, but if you live in a rural area, you’ll certainly want to keep that wire antenna handy.
On one hand, the wire antenna is easier and more flexible to deploy than attached telescopic antennas, which can be bent or broken. But on the other, an external wire antenna is just another item you’ll need to pack and take along with the radio if you plan to listen via the internal speaker.
If you plan to listen with headphones, however, no worries! I find the sensitivity with headphones inserted to be just as effective. In fact, instead of taking along the wire antenna you could bring the included headphones, and they’ll double as an external antenna while listening via the internal speaker. In my tests, the headphones performed about as well as the external wire antenna.
My advice? If you purchase the DT-800, either keep the small wire antenna or a pair of headphones nearby to insure you’re getting the best FM reception.
Weather Band
The same notes above about the necessity of an external wire antenna apply on the weather band as well as the FM band.
With the wire antenna or a set of headphones connected, weather radio reception is good. I was able to receive both of my local NOAA weather reference frequencies.
To be clear, the DT-800 is not as sensitive as my C. Crane CC Skywave or CC Skywave SSB––which are truly WX band benchmarks––but it will likely receive your local NOAA or Environment Canada broadcasts as well as most other weather radios.
The DT-800 also includes a Weather Alert feature, but as Sangean notes, you should only use this feature while the radio is plugged into mains power, as it will drain batteries about as effectively as if you were listening to an FM radio station.
AM/Mediumwave Band
If there’s a weak point on the DT-800, I would say it’s the AM band.
Don’t get me wrong: at first blush, the DT-800 looks like a little Ultralight DXing dream, as it’s loaded with great features, such as:
multiple bandwidths (wide/narrow),
9/10 kHz spacing,
well-balanced AGC (auto gain control),
as well as the ability to turn off soft muting.
Yes, the DT-800 has the ability to disable soft mute.Thank you, Sangean! So far, Sangean seems to be one of the only radio manufacturers that enables this DSP chip option in their product line. Another receiver with the ability to disable soft mute was the Sangean ATS-405 (check out our ATS-405 review). I wish other radio manufacturers would do the same because soft mute is what often makes listening to weak mediumwave signals so fatiguing. With soft mute disengaged, weak signals enjoy better audio stability as they’re not fighting to stay above the muting threshold.
But, I’m sorry, DXers: unfortunately, the DT-800’s weakness on AM is the same as the ATS-405 on AM (and shortwave): a higher-than-average noise floor. Somehow, internal noise is being generated and not being contained by shielding and grounding.
I made a short comparison video to demonstrate the noises heard via the DT-800. Before you ask: yes, these noises are present regardless of radio location, or whether or not there are other radios nearby. In addition, I made this video on a folding table far away from my house or any other potential sources of noise (with the exception of my iPhone which was used to make the video). This is the same low-noise spot I use to do comparison tests of all my portable receivers:
As I note in the video, the noise floor isn’t consistent across the band––some parts are lower, other parts higher. One of the noise peaks is around 1600 kHz which, unfortunately for me, is where my favorite local AM station resides.
So is this a deal-breaker? No…not necessarily. For the casual AM radio listener––a listener primarily focused on listening to local AM stations––I think the DT-800 will please. In fact, I might not have noticed the elevated noise floor had I not: 1) listened to weaker AM stations, and 2) compared the DT-800 with other radios.
Since I’ve been using and listening to this radio for the better part of a month, I can state with confidence that most of my other portables outperform the DT-800 on mediumwave. I compared it with these rigs:
Sony ICF-S10MK2
Tecsun PL-310ET
CC Skywave
CC Skywave SSB
Radiwow R-108
To be clear, I believe the DT-800 has average MW sensitivity for a radio this size, but the noise floor sort of spoils any hopes of doing marginal or weak signal work, thus also making that awesome soft mute toggle less effective.
If you pair the DT-800 with a loop antenna like the AN200, which I highly recommend doing, it will help those weak signals rise above the noise. Otherwise, if your primary goal in purchasing the DT-800 is to listen to mediumwave, I regret to say, you might want to take a pass on this one.
Summary
Every radio has its pros and cons. Each time I begin a review of a radio, I take notes from the very beginning so that I don’t forget my initial impressions and observations. Here’s the DT-800’s list, from the first moments I turned it on, to the time of writing this review:
Pros:
Great overall performance on FM
Quality construction and thoughtful ergonomics
Both clock and alarm for the traveler
Ability to switch between FM stereo/mono with headphones in use
Wide/narrow AM and FM filters
NiMH AA batteries can be recharged internally [make sure switch inside battery compartment is set to “NiMH”]
FM RDS (one mode)
Mechanical keylock switch
Ability to disable soft mute (other radio manufacturers take note!)
Small internal speaker providing quite decent audio
Comprehensive gear package includes radio, manuals, quality earphones, quality AC adapter, wire antenna
DC port is standard MicroUSB
Belt clip
Built-in speaker
Dynamic Bass Boost
Cons:
While listening via the DT-800’s internal speaker without antenna wire or headphones inserted: FM performance is lacking, while weather radio performance is very much lacking
AM band: Noise floor is higher than on comparable radios
Conclusion
The Sangean DT-800 is a solid little radio: it’s simple to operate and feels like a quality piece of kit. It’s perfect for hiking, or any sport or task where you’d like one-hand operation.
The DT-800 also has a surprising amount of features and customization through the menu settings––much more than one would expect––which puts it firmly into what I would call the “enthusiast-grade” radio category.
It’s for this reason that it’s a bit disappointing AM reception on this Sangean isn’t better.
The DT-800 has a lot of icing on the cake, otherwise: FM RDS, the ability to internally recharge AA batteries, built-in speaker, Dynamic Bass Boost, multiple bandwidths on AM and FM, the ability to disable soft mute–all of these are essentially pro features.
So, if you’re looking for a quality portable radio primarily for FM and WX band listening and perhaps catching the odd local AM broadcast, the DT-800 is a great choice.
Many thanks to SWLing Post contributor, Al Holt, who writes:
Your readers may be interested in tuning in the daily (except Sunday) broadcasts of Marine Weather Center on 4045 and possibly 8173, 12,350 kHz. These broadcasts use upper sideband mode. https://www.mwxc.com/index.php
It’s described as, “custom weather and routing information for small vessels in the Caribbean Sea, Bahamas and United States East Coast,” and is based near Lakeland, FL.
As a subscription weather service for pleasure craft, but they provide an interesting roundup and forecast of weather in this area of the world. They do take questions and traffic from subscribing vessels at the conclusion of their broadcast.
I am usually am able to receive the omnidirectional broadcast on 4045 kHz here in northern Florida. But, their coverage at greater distances is pretty good I think.
The chart below (taken from their ‘Services’ page https://www.mwxc.com/marine_weather_services.php ) shows this broadcast starting at 1100z, but I usually hear them closer to 1200z and that may be due to atmospheric conditions. I haven’t had much success catching their later transmissions. I’m not sure how often their webpage gets updated and schedule changes are probably relayed privately to their subscribers.
Wow! Thank you so much for sharing this information, Al.
Post Readers: I know there are a number of SWLing Post readers who sail and cruise (some on very long voyages)—I’m curious if any use the Marine Weather Service regularity. Please comment!
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