DigiFAQ Updated: An HF Digital Decoding primer and reference tool

Many thanks to SWLing Post contributor, Mike Agner, who writes:

[S]ome 20 years ago, Mike Chace-Ortiz, Stan Skalsky, myself and a bunch of other folks put together a FAQ about digital modes on radio – specifically modes going from LW way up into the UHF spectrum- called the DigiFAQ 5.3. I was responsible for the HF Software section, and as you might know, back then it was all about the hardware. InfoTech was still around, and amateur digital modes using the PK232 were plentiful. There is a PDF-based copy on the UDXF website [click here to download].

Now jump ahead 20 years or so, and things have changed considerably. Hardware is no longer king, and soundcard-driven software has taken over the market. Even receivers have changed – the desktops of old (quite apart from the current batch of ham transceivers that have general coverage radios built in) have been pretty much supplanted by Software Defined Radios. Along with that, the digital modes themselves have changed drastically with some disappearing altogether, with new ones like ALE going to the head of the pack. Too, the original DigiFAQ combined many ham-related modes along with everything else.

[O]ur original work didn’t really address some of the basic questions newcomers to this side of the hobby might have, [s]o with Mike Chace-Ortiz’s help, I have been involved in rewriting and updating the FAQ. Its approach is different – we start from topics like discussing radios, SDRs, some of the terminology you will see on mailing lists like the UDXF and much more. Only after we cover all of this do we discuss decoders – and even here, this topic is broken down even further, to include those decoders that play nice with some SDRs, and some of the tools you can use to help analyze an unknown signal.

Then we go into the modes (most are HF related, but we do touch on one or two common LW modes). We identify those modes that are dead, and separate them from the rarely used/active ones. Where possible we also supply waterfalls for each.

We also have an extensive appendix with a whole bunch of links for additional reading.

Perhaps of greatest use to newcomers is a listing of known scheduled broadcasts, so they can test what they download without wandering all over the place, hoping to find a readable signal – and potentially getting turned off when the don’t find one. We have also recovered a few articles from the old WUN archives as well as from SPEEDX (Society to Preserve the Engrossing Enjoyment of DXing – folded a long time ago) on certain digital related topics, such as discussing how to read an AMVER transmission.

It should be noted that we also sent the amateur radio digital modes to their own page for a very simple reason – while these modes are well understood (and many have their own devoted page that cover their mode far better than we can), the single biggest reason was that these modes can NEVER be encrypted (at least in the US, and likely other countries as well). Sad to say, but there are many modes outside of the amateur bands that we will never be able to read, and some whose purpose is unclear. As of this writing, many UDXF members are noting signals thought to be Russian in origin, utilizing a variation of MFSK-16, a mode generally associated with amateur radio.

Is this document complete? Not even close. It’s designed to be something of an introduction, with enough detail to hopefully draw in both the newcomer and experienced. There are new modes being identified, new networks, and even new players being found all the time. There’s still more work to be done on this, and this is yet another change to the original DigiFAQ- it’s hosted on the RadioReference wiki, where any member (with a free ID) can edit and add to it.

The URL is: http://wiki.radioreference.com/index.php/HF_Digital_Decoding

Regards, Mike

Thank you for sharing this update, Mike!

I receive a lot of questions regarding digital modes even though it’s an area of the hobby where I’m quite weak. I’m pleased that you, Mike, Stan and your team are all working to keep a reference source up-to-date for folks exploring this dynamic part of the radio hobby.

Click here to visit DigiFAQ at RadioReference.com.

From the Isle of Music, 19-24 December

From the Isle of Music, week of December 19-24

This week, our special guest will be Degnis Bofill, an emerging young percussion star in Cuba who received two awards in this year’s JoJazz competition. We’ll have a brief interview and some music that features him on percussion. Also, in honor of their GRAMMY® nominations, we will feature music from Los Van Van’s La Fantasia and Chucho Valdes’ Tribute to Irakere. And, as always, other good things.
Three options for listening on shortwave:
WBCQ, 7490 KHz, Tuesdays 0100-0200 UTC (8pm-9pm EDT Mondays in the Americas)
Channel 292, 6070 KHz, Fridays 1100-1200 UTC (1200-1300 CET) and Saturdays 1600-1700 UTC (1700-1800 CET)*
*The Saturday broadcast may receive interference from the Voice of Turkey in some areas but should be audible in the UK and NE Europe.
See our Facebook page for more information

 

Norway becomes first country to go “fully digital”

(Source: RadioInfo via Kris Partridge)

11th January 2017 is a historic day for the medium of radio.

Norway becomes the first country in the world to move towards fully digital radio transmissions. As a result of this, the national FM network will be switched off.

The FM networks will be switched off region by region, starting in Nordland 11th January. The event will take place in Bodø and the final switch-off will be done at 11.11 pm CET.

The heads of NRK radio and commercial radio will be in Bodø to represent the Norwegian radio industry. Also, head of BBC radio, Helen Boaden, and head of radio at EBU, Graham Dixon, will attend.

An international seminar for European broadcasters will be held the day before the historic move to FM switch-off and an international press-conference will be broadcast on radio.no at 2 pm CET.

The final program will be published nearer to the event.

Read more at: https://www.radioinfo.com.au/news/norway-makes-radio-history © Radioinfo.com.au

Guest Post: Remembering our Elmers

Photo: Mario Filippi (N2HUN)

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


‘Tis the Season to be Jolly and to Remember Our Elmers

by Mario Filippi (N2HUN)

At this time of year when we gather with friends, family, coworkers and acquaintances to share the bonhomie and joys of the holidays let us fondly remember those who brought us into this hobby, our dear Elmers, those individuals who’ve given of their time teaching us the basics of ham radio, answered our endless questions, inspired us by their shacks, guided us through the difficulties of radio theory and good operating practices and proctored us through our first examinations. If it weren’t for these selfless individuals, who followed a time-honored tradition of mentoring budding hams, the hobby would not continue on and most of us might have taken other paths and missed out on a life-long, very rewarding hobby.

To start the ball of reminiscences rolling, take a seat with me in the time machine of memories and go back to the early 1970’s, to the suburbs of White Plains, NY, the home of my Elmer, may he rest in peace, George Buchanan, WB2FVX (SK).

George held Novice classes once a week in the basement of his home where he tutored a gaggle of ham wannabes consisting of grammar school kids to those of advanced age, some of whom were old railroad telegraphers schooled in the use of sounders. We’d have an hour of lecture, followed by code practice, then the class would end with general socializing amongst the students as to what transpired along with our future plans for our “shacks.”

You know, George did not quit his day job to train us through our larval stages of the hobby; as a matter of fact he commuted to the city every day and still found the time once a week to start his 7:00 PM class for his eager students, and always had energy after a long day’s work to stand in front of his chalkboard and work out the numerous electronic calculations (OHM’s Law, parallel and series circuits of resistors and capacitors, antenna resonance and impedance ) and list important regulations that would be included in our FCC Novice exams. At the conclusion of the three month course, George sat through our Novice exams and mailed them off to the FCC Office in Gettysburg, PA. Back then it took a few months before you’d get your license and hold in your hand the fruits of your (and your Elmer’s) labors.

George has been a silent key for decades now, and he frequently comes to mind, especially during the holiday season, when thoughts of Christmases past and all of the pleasant memories of almost forty years in the hobby occupy my mind. Indeed, George and all the other Elmers out there, living and deceased, have bestowed upon us one of the greatest gifts of all – Amateur Radio.

Think back on your Elmer and do so with fondness and when the opportunity presents itself, take an inexperienced ham under your wing, guide them, inspire them, show them your shack, answer their questions, help them pick out a rig or accessory, have a QSO with them, help them with troubleshooting, accompany them to a hamfest, share the joys with them when they purchase a piece of equipment, and most of all, be there for them.

Merry Christmas and Happy New Year to all!


Thank you, Mario, for sharing these special memories with us! George was an ideal Elmer indeed–he had the ability to share his enthusiasm and passion with others and helped them obtain their license during a time when study materials were not so readily available (and the test was much more challenging!).

Thank you, Mario!

Troy reviews the Audiomax SRW-710S

Many thanks to SWLing Post contributor, Troy Riedel, for the following guest post:


A Mini-Review of the Audiomax SRW-710S

by Troy Riedel

Why would someone want a sub-$20 shortwave radio? Wait … I guess I should be answering questions & not asking them, right? But I’ll give you my answer to “why I want a sub-$20 shortwave radio”: I have many nice radios, but I wanted one that I consider “disposable”. I define “disposable” as something I won’t be upset if I lose, get it splattered with paint, or leave it outside only to get rained on. Taking the family of four to the movies nowadays costs upwards of $100 (the three ladies I live with can really throw-down pop & popcorn!) so a sub-$20 radio, even a “disposable one”, is a true bargain.

I have seen the SRW-710S badged under three different names: Audiomax, VITE and TIVDIO. There very well may be other badging. I paid $18.52 for my Audiomax badged device direct from a vendor in China. I’ve subsequently seen it as low as $13 on eBay and as much as $37 on Amazon. So much for a sub-$20 radio, huh?

The SRW-710S comes with only a USB charging cable in the box to recharge the Li-ion BL-5C battery (no earbuds, no case or pouch – just a very simple set of basic instructions). The 710S features a small LCD screen that offers menus in three languages: English, Spanish & Chinese.

The screen greets you with “welcome” (lowercase) when turning it on & “Bye Bye!” when you power-off. There is a Sleep Timer function that I have yet to use. All of the ports are on the right side of the unit (nothing on the left). It has a TF Flashcard Slot – no card provided – for recording off the radio & for playing pre-loaded mp3 & wma files from the flashcard.

It has 100 memories, a Line-In port, a built-in mic, and a headphone port. There is no ANT-In port. This radio has AM, FM & SW (no LW) with the appropriate international tuning steps. Lastly, there is no folding stand on the back (one is provided and is attached to the wrist strap – it is inserted into a small slot just above the battery cover).

One Chinese web site listed the SRW-710S as having an “AKC6951 DSP chip”. Until now, I had never heard of this DSP chip and I frankly know nothing about it. Maybe some more informed readers can comment?

Operation is easy (except for one quirk that I will detail later). There are two rows of numbers for direct input of a frequency. Simply input the frequency … and then wait (there is an approximate 3-5 second delay from input to the radio actually tuning to the frequency … I am still getting used to this pregnant pause). You also have an option of tuning directly to a meter-band.

Of course, there is no SSB for this low price.

The one speaker is a bit “tinny” but adequate (stereo via user-supplied earbuds). And considering the price point, the RF shielding isn’t too bad. I can actually use the shortwave band of this radio in my kitchen and breakfast nook (I cannot say that for my more expensive receivers).

The biggest limiting factor in reception is the size of the telescopic antenna (15.5”). However, for its size I am quite impressed (it’s exponentially better than the old Grundig G2000A Porsche that has a 21.25” antenna – but that radio is notorious as needing a reel antenna). Just via the telescopic whip, I can actually tune the major broadcasters to NA (e.g., Radio Romania), I can adequately tune to the VOA 15.580 MHz signal to Africa during the North American East Coast AFTN, and the time signals are easily audible (of course, frequency appropriate for the time of day).

I do not plan to open the radio’s chassis, but AM reception seems to be limited due to the obvious small size of the ferrite antenna (the radio itself is essentially palm-sized, approximately 4.75” x 3” & less than 1” thick). My postal scale indicates it weighs 5.5 – 6 ounces including the battery. The radio must be propped to support it when attaching the telescoping whip to a Slinky Antenna (even the weight of the Slinky’s alligator clip causes balance problems)
One quirk I have found: there is a “Lock” key. However, it only seems to lock the radio power “on” (locks are used to lock the power “off” during transport so the power remains off and the battery doesn’t drain). The “Lock” feature is not discussed in the instructions and at present I have not figured-out if this switch works in the traditional way. I find this to be quite amusing because it’s either an odd quirk or I’m just not smart enough to intuitively figure it out.

I am quite satisfied with my new “disposable” $18.52 Shortwave Radio (I have no information whether the quality I have considered is consistent through a production run or between badging). For those who wish to listen to a local AM or FM station – or listen to one of the “major” shortwave broadcasters with a booming signal into your part of the world – you can’t beat it for this price point. I can see myself using this radio while I complete outdoor household repairs or while cleaning-up the garage. Too bad it’s so close to Christmas, this would make a great stocking stuffer to introduce someone, young or old, to the world of shortwave.

Update: Searching for the SRW-710S

Note that the lowest prices omit the model number in eBay search results.

Click this link to search eBay for the SRW-710S on eBay. 

Scroll through search results to find a matching receiver.


Thank you, Troy, for mini-review of the SRW-710S! Like you, I have very low expectations from shortwave portables at this price point. Still…for the glove compartment of your vehicle, for outdoor listening, for small gifts? These fit the bill! I’m most impressed you could receive the number of stations you did from inside your home. 

December Contest: Your holiday radio memories!

My Hallicrafters SX-24 in the holiday spirit!

[Update: This contest is over, but you can read all of our radio memories on this Christmas Eve post.]

It’s the winter holiday season here in North America, typically a great time to slip into the shack, sip some warm mulled cider/eggnog/coffee, and explore the world via the shortwaves, mediumwaves, and longwaves. Truly an experience of comfort and joy.

Fred Osterman at Universal Radio contacted me recently and offered to support a little contest to celebrate the holiday season–with a little gift!

The contest

We’ve put together a simple contest; both a US and international winner will be chosen at random. All you have to do is share the following with us using the contest entry form below:

Do you have any special holiday memories that involve…well, radio? Perhaps you remember a seasonal broadcast, received a special radio as a gift, or otherwise enjoyed the holidays through radio? Please share your story!

Of course, this contest encompasses any holiday–Christmas, Chanukah, Kwanzaa, Ramadan, Easter, or any other religious or secular holiday in which a particular radio memory played a part.

We’ll select a number of these memories and share them in a post here, just to put us all in the holiday spirit.

The Prize

Universal is offering a handy Grundig Edition Eton Mini to our US winner and another to our international winner!  Merry, merry!

How to enter

Simply fill out the form below (or by clicking this link), and share your story. Please only enter this contest if you’re willing to share your story with others.

This will be a short contest:  all entries must be received by 00:00 UTC on Sunday, December 18, 2016.

We’ll announce the winners, picked at random, on Monday December 19th, 2016, and the holiday prizes will be shipped the same week.

We look forward to your holiday stories!

A special thanks to Universal Radio for sponsoring this holiday contest!

Alan Roe’s B16 guide to music on shortwave radio

Many thanks to SWLing Post contributor, Alan Roe, who shares his updated  Music on Shortwave list for the B16 period. Alan’s music guide incorporates several suggested additions by SWLing Post readers.

Alan, again, thank you so much for publishing this brilliant little guide!

Click here to download Music on Shortwave B-16 (PDF).