About two weeks ago I was lounging around in the backyard drinking an iced tea and reading the July issue of QST when I stumbled on something I thought was really sweet. The Voice of America is broadcasting weekly radiograms! I didn't even know the Voice of America was still in existence, so it was awesome to hear they are still around. It's doubly-awesome because the Voice of America Radiogram is an all digital broadcast which means you need to be into digital modes to receive it and I am very into all things digital. My first attempt at googling the website for VOA landed me on the VOA News website here http://www.voanews.com - which is not what I was looking for. (I should note however, there is a LISTEN button in the top right corner of the page that will allow you to listen to the VOA over the interwebs which is mildly interesting for a little while.) Further research revealed the radiogram site is located at http://voaradiogram.net. Scanning around the page revealed the following transmission schedule (all days and times UTC):
Sat 0930-1000 5745 kHz Sat 1600-1630 17580 kHz Sun 0230-0300 5745 kHz Sun 1930-2000 15670 kHz
These seem to be standard times used every weekend (but don't take my word for it, check the VOA website before planning any activities). The page also mentions the radiogram broadcast is transmitted from the Edward R. Murrow transmitting station in North Carolina. After futzing around converting UTC into local time, I discovered the Sunday 0230 UTC broadcast would be 7:30pm AZT which was just perfect! I was less sure about picking up North Carolina from Arizona (a distance of approximately 1,800 miles), but I decided to give it a try.
My receiver for this experiment is a Tecsun PL660 'PLL World Band Receiver' connected to a 40meter-ish dipole antenna oriented east-west in my attic. I say 40meter-ish because this antenna is approximately 66 feet long, but isn't used for transmitting and is connected to my radio by a rather rube-goldberg-esque run of feed line. The computer used is an old homebrew 2.4GHz Pentium 4 with 1 Gig of RAM running Windows XP SP3. As the Voice of America Radiogram website recommends, I downloaded and installed fldigi available from https://sourceforge.net/projects/fldigi/files/fldigi and flmsg from https://sourceforge.net/projects/fldigi/files/flmsg. I also found this bit of useful configuration information on the Voice of America Radiogram website:
"To make Flmsg work with Fldigi, in Fldigi: Configure > Misc > NBEMS > under Reception of flmsg files, select Open with flmsg and Open in browser, and below that indicate where your Flmsg.exe file is located – probably somewhere in Program Files(x86)."
My first step was to see (generally) what reception was like. The Voice of America Radiogram was listed as broadcasting on 5745kHz, so I tuned to the WWV beacon at 5000kHz to listen to Colorado for a little while. WWV was audible but with some pronounced fading in and out, so I wasn't overly optimistic I was going to hear the VOA clearly enough to decode anything. The audio is a little strained, but if you turn up your volume you can hear my reception of WWV in this video. When 7:30 AZT finally rolled around I strained to hear anything and... nothing. I was starting to think I had the time wrong, or my flaky antenna arrangement wasn't up to the task, or the reception conditions weren't right, or... Then I heard the music and the infamous "Voice Of America" introduction and got goose bumps. After that, the whole shebang was almost idiot proof. fldigi started decoding MFSK32 and I was kind of amazed how reliable it was. Here you can see everything in action (with a brief shot of my PL660 about halfway through). As this portion of the program was about to wrap up, it occurred to me that some of the programs in the radiogram contain images. I wanted to be sure I had a video of receiving my first image via MFSK32 but unlike the awesome slow scan television (SSTV) images I received from the ISS last year (Image1, Image6, Image8, Image9), the received image was a little underwhelming. I also recorded my reception of two other images from this radiogram. If you are really interested, you can watch them all on YouTube. VOA Radiogram 173 (4 of 7) VOA Radiogram 173 (5 of 7) VOA Radiogram 173 (6 of 7) The final portion of the program was an encoded HTML message about the Kepler Space Telescope. This is where flmsg comes into play. It looks like the message is encoded and transmit as a Base64 string, which is then decoded and launched in your favorite web browser. I'm doing some extrapolation here, I don't know how the data is encoded for sure, but when you see something like this
it sure smells like Base64 encoding. After looking at the received HTML document, its a bit of a cheat. Yes, the HTML was received via MFSK32 but the linked image and (obviously) hyperlinked content point to URLs on the interwebs, which (to me) feels like it violates the spirit of the whole thing. You can see the decoded HTML message thanks to the wonderful folks at YouTube. VOA Radiogram 173 (7 of 7)
I never expected that I would be able to copy the entire program without any data loss. The images looked a bit sketchy, but these days any image that's only 200x180 pixels with artifacts looks pretty bad. You just have to remind yourself how you received those sketchy looking images. That's the cool part. I made sure to capture my audio with fldigi and have provided a download link to the audio and the full broadcast text below. I was unable to figure out how to 'save' the received images with fldigi, so I unfortunately don't have any links for the received images, but trust me, your not missing anything. VOA Radiogram 173 Text VOA Radiogram 173 Audio All in all, this was a great first-time experience with receiving MFSK32. If you've never done it, the VOA Radiogram is a fantastic way to get your feet wet. I highly recommend giving it a try! 73