Decoding DRM shortwave broadcasts (IC-7300 configuration)

This turned out to be really simple.

Step 1: If you haven’t already done it…Get the transceiver connected to a PC using the USB cable and appropriate drivers.  When this is successful, you should have the ability to get sound from (Microphone – USB Audio Codec) and send sound to (Speakers – USB Audio Codec) the transceiver in your PC “Audio” options.

Step 2: Get Dream.  It’s available at Sourceforge.  No install is needed, just unzip the folder and put it somewhere you can find it.

Step 3: Get the codec.  Search for “faad2 audio codec”.  The file “faad2_drm.dll” needs to be put into your Dream folder.

Step 4: Transceiver setup.
a) MENU – SET – Connectors – ACC/USB Output Select.  This should be set to “IF”.
b) Tune DRM broadcast.  Set your transceiver to “AM”.  Set the bandwidth to 10 kHz (i.e. -5kHz / +5kHz)…I think it’s as wide as you can go on the 7300.
c) Start Dream by double-clicking the “dream.exe” file in the Dream folder. Then go to “View”…”Evaluation Dialog” to open the detailed signal dialog.
d) Not all Dream signals you see will be decodable.  It seems to take a fairly high signal-to-noise ratio to get a solid audio decode and most broadcasters don’t aim their signals at North America anymore.  Something like +16dB at least.  +20dB works very well.  You can decode the metadata (station, transmitter location) at lower SNR.


Updated: February 2, 2018 — 6:16 pm


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  1. Hi,
    There seems to be something missing here. What do you pick for the channel? I+Q? L+R?

    1. Sorry….I just saw this. Need to fix notifications, I guess. Have you had any success? Anyway, I just checked my settings. In Dream: Settings…Sound Card…Signal Input…Channel, I’m just using ‘L + R’. I don’t recall explicitly setting this, so perhaps it’s the default. Unfortunately, good DRM signals are hard to come by, so I can’t verify this by doing a decode just now.

  2. Dan — couldn’t fine email on, thus this “comment” ? for you. You say search for “faad2 audio codec” I did find it at source.forge downloaded it and unzipped it. Got a file folder called faad2-2.7 which had a lot of stuff in it. I couldn’t find “faad2_drm.dll” in it.
    what am I supposed to do? Put the whole big file folder into the Dream folder?
    73 de Jim, KH6HTV 3/31/19

    1. Hi, Jim.
      If you have a zip file with a lot of stuff in it, you might have downloaded the source code instead of the binaries. However, in looking at the binaries on sourceforge, I don’t see the correct .dll file in those. So, either something has changed or I misstated how I found them.
      Anyway, if you go to the below page, there is a link to the faad2_drm.dll file that should get you going.
      Let me know how you make out, please. It can be discouraging because there is so little in the way of DRM receivable here in the US. Radio Romania and the BBC are the only ones that I’ve ever heard here, and most of the time I can’t even hear them.

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