[A-DX] bald DRM-Piraten?

["Harald Kuhl" <HKu-DX@xxxxxx>]

Moin,

folgendes entstammt http://www.eham.net/articles/8699

Man kann also ohne Modifikation über einen herkömmlichen SSB-Sender auch DRM
schicken. Würde mich gar nicht wundern, wenn wir demnächst die ersten
DRM-Piraten auf 48m oder 6670 hätten...

Gruß,
Harald



First Release: Digital Voice on Shortwave:
Andreas Weller (DF1PAW) on June 28, 2004 
View comments about this article! 

Hi!
As most hams will know DRM (digital radio mondiale) is the upcoming digital
shorwave 
broadcast standard. There are two different decoders at the moment: the
commercial by
Fraunhofer - http://www.drmrx.org/ and an open source project at 
http://www.sourceforge.net/projects/drm/
The open source decoder included a transmitter mode in the current CVS
version. With it 
you are abled to transmit slide show pictures but no voice as there's no
free DRM compatible
AAC encoder. You also have to modify your tranceiver for the 10 kHz
bandwidth signal. 
Now HB9TLK modified this software and included Hawksoft's LPC-10 audio
compressor - 
http://www.hawksoft.com/hawkvoice/ - to the DReaM proejct.
As LPC-10 allows very high compression rates (of cource not at HIFI quality)
the signal fits
into a normal SSB channel so you don't even need to modify your
transceiver's filters.

Of course this is not a DRM compatible mode as it doesn't use AAC
compression and 
doesn't have the required bandwidth but it seems to allow digital voice QSOs
on HF with a 
standard PC/transceiver only.

DReaM runs under Windows and Linux and is released under the terms of the
GPL licence. You
can download the binaries and the sources for free under
http://www.qsl.net/hb9tlk/hamdream
Links:
http://www.qsl.net/hb9tlk/hamdream
http://www.sourceforge.net/projects/drm
http://www.hawksoft.com/hawkvoice

I also mirrored hamdream on my server as QSL.NET seems to be quite slow at
the moment...


Regards,
Andreas Weller, DF1PAW



Member Comments: Add A Comment 
First Release: Digital Voice on Shortwave:  Reply  
by SP5QIP on June 28, 2004  Mail this to a friend!  
I tried it with my friend. It is nice, a little hard to set up, but after
proper connecting to the rig, it`s working good. I`m waiting for standalone
version of this. A lot of fun is also to receive drm hf braodcast. 
Mike  
  
RE: First Release: Digital Voice on Shortwave:  Reply  
by KF7CG on June 28, 2004  Mail this to a friend!  
How well will this mode operate in the presence of BPL(PLC) interference at
a signal to BPL ratio of 70db. If it will work we all might need it.  
  

-- 
+++ Jetzt WLAN-Router für alle DSL-Einsteiger und Wechsler +++
GMX DSL-Powertarife zudem 3 Monate gratis* http://www.gmx.net/dsl

-----------------------------------------------------------------------
Diese Mail wurde ueber die A-DX Mailing-Liste gesendet.
Admin: Christoph Ratzer, OE2CRM  http://www.ratzer.at
-----------------------------------------------------------------------
Private Verwendung der A-DX Meldungen fuer Hobbyzwecke ist gestattet, jede
kommerzielle Verwendung bedarf der Zustimmung des A-DX Listenbetreibers.