DRM from Sackville Clear as a Bell
 

DRM transmissions from Sackville NB, Canada on 9.800MHz, had no drops today.
Starting with Deutsche Welle (Germany) on to Radio Sweden's 60-degrees
North, finally followed by BBC World Service. In addition, DRM from Radio
Kuwait on 11.675MHz was very readable with quite a few drops. The quality of
audio of the DRM transmissions was excellent. Musical pieces were as though
they were coming from a local source. No static crashes, no fading, just
clean sounds.

I use both the Dream software as well as the Merlin DRM decoders. This isn't
conclusive but I believe the Dream software has less drops than the Merlin
software, and it's free.

I'm hoping for more stations using DRM transmission modes. It makes SWLing a
pleasure.

Al KA5JGV
San Antonio, Tx.

In article ,
"Al" wrote:

DRM transmissions from Sackville NB, Canada on 9.800MHz, had no drops today.
Starting with Deutsche Welle (Germany) on to Radio Sweden's 60-degrees
North, finally followed by BBC World Service. In addition, DRM from Radio
Kuwait on 11.675MHz was very readable with quite a few drops. The quality of
audio of the DRM transmissions was excellent. Musical pieces were as though
they were coming from a local source. No static crashes, no fading, just
clean sounds.

Snip

You mean you thought the sound quality was good in between the drops.
Taken all together though would you call the reception from Kuwait good?

How long were the drops in time? How often was the signal dropped?

--
Telamon
Ventura, California

"Telamon" wrote in message
...
In article ,
"Al" wrote:

DRM transmissions from Sackville NB, Canada on 9.800MHz, had no drops
today.
Starting with Deutsche Welle (Germany) on to Radio Sweden's 60-degrees
North, finally followed by BBC World Service. In addition, DRM from
Radio
Kuwait on 11.675MHz was very readable with quite a few drops. The
quality of
audio of the DRM transmissions was excellent. Musical pieces were as
though
they were coming from a local source. No static crashes, no fading, just
clean sounds.

Snip

You mean you thought the sound quality was good in between the drops.
Taken all together though would you call the reception from Kuwait good?

How long were the drops in time? How often was the signal dropped?

One of the neat features of both the DRMrx and DReaM software DSP decoders
for DRM is the logging of SNR and rate of successful audio decoding. Using
another software, DRMcalc, you can view the logs graphically. There are many
of these graphs posted in the DRM Software Radio Project web site in either
the Analysis Area or in the Forums at http://www.drmrx.org/ . Have a look to
see what dropout rates and durations are being encountered. With hf skywave
propagation, experience one day is no predictor of performance for the next.
You may have an incredibly strong signal but the multipath scattering could
be so great that the decoder mutes - I often see that on Sackville
transmissions in Toronto. OTOH, the signal may be relatively weak but less
scattered and the audio will be reliable. I sometimes see that on long
distance paths, e.g., from Kuwait.

Sackville is now experimenting with 2-channel stereo transmission on its
TDPradio relays on Saturdays. Don't believe anyone's claims that this is
near CD quality - you aren't going to get that at 20 kbps. But the stability
of the audio frequency response (absence of the effect of selective fading
that we are so familiar with for SW-AM) and the absence of heterodynes while
perceiving an audio spectrum greater than 5kHz is a remarkably different SW
listening experience. When propagation is favorable, you forget you are
listening to SW! The problem is getting close to 100% successful audio
decoding for extended listening periods, day after day....

Tom