After reading this site : http://paginas.terra.com.br/lazer/py4zbz/hamdream/rxdrm.htm I modified my Icom IC725 with a similar capacitor. It worked more or less. Switching to the CW-N mode on my trx and decoding with Dream I could listen to some DRM radiostations. At that time the only antenne I could use was a magnetic loop, mounted near the window. Not the setup that everyone dreams of 🙂
I posted two very small video’s on youtube. They were shot with my Canon Digital Photocamera and the recording was limited to 30 seconds.
The videos :
Last summer I tried it again with the current antenna setup. But instead of using the audio via the 100nF tap, I used the audio that is feeding my PSK interface box via one the ACC connections at the back of the transceiver. This also works pretty well. Keep in mind that you have tune approximately 7 to 10 kHz below the carrier frequency of the radiostation. If I want to listen to the BBC on 1296 Khz, I tune to 1289 or something like that. It is a bit trial and error.
Below are MP3 recordings I made last june of receiver stations (click to hear it or rightclick and Save As to save it on your local harddisk) :
- BBC World DRM on 1296 kHz 15/06/2008
- BBC World DRM 14/06/2008
- BNR Digital DRM on 11900 kHz 15/06/2008
- Deutsche Welle DRM on 13810 kHz 15/06/2008
- Voice Of Russia DRM on 12060 kHz 15/06/2008
- MOI Kuwait DRM on 13620 kHz 15/06/2008
The software to decode the DRM audio I use is called DReaM, The source can be downloaded here: http://drm.sourceforge.net/
You can find a compiled version on the web by using Google.