13 April 2003, 6140 kHz, DW Juelich,

(TS440 + FM pickup point + FM mode, ant dipole 2x7m on
balcony + 5m coax cable + IBM Netvista A30P P4 1.8G
built-in soundcard).

Moving to here after listening to Sines on 15440kHz where
results were quite correct.

Signal level is high but the SNR remains strangely N/A.
See PHOTO here .  (well, doesn't work).
The cause will be identified later, see below.

>>>>

>>>
After this, I switch back to Sines 15440 kHz  and it
works perfectly.

After also trying my ACER Notebook on 15440 with quite
good result, I come back to 6140 kHZ, still with
ACER TravelMate 506 T Notebook
Celeron 433, Windows 98, RAM 64Mb,
Included sound device : Crystal WDM Audio 5.00

>> The result is very poor !!
 

>>>>
Computer : ACER TravelMate 506T (Testing)
DRMSoftwareRadio-MERLIN-00000127
Software Version 1.0.21
Starttime (UTC)  2003-04-13 12:00:34
Frequency        6140 kHz
Latitude         44°49'N
Longitude         0°38'W

MINUTE  SNR     SYNC    AUDIO     TYPE
  0000   13      150   180/10        0 12H00
  0001   11      151    86/10        0
  0002   12       30    58/10        0
  0003   11       32     0/10        0
  0004    0        0     0/00        0
  0005    5       46     0/10        0
  0006    8      154     1/10        0
  0007    5       26     0/10        0
  0008    5       54     0/00        0
  0009    7       83     0/10        0
  0010    9      150    15/10        0 12H10
  0011   11       63     0/10        0
  0012    5       13     0/00        0

Around here, I find out that a peak on 6142 kHz
on the spectrum display, is actually caused by...
the monitor display of my IBM which was still on, even
if not used here... Had never happened yet on
other frequencies. Will have to look at it.
This same problem explains the nil result obtained
above at 10h-10h44 !
Below, I must have switched off that display.
Result still poor. We will see reason is that
computer is probably not suitable.
 

  0013   10      120   181/10        0
  0014   11      136   427/10        0
  0015   12      149   486/10        0
  0016   12       80    24/10        0
  0017   13      151   565/10        0
  0018   10      107   132/10        0
  0019    8       96     0/10        0
  0020   15      150   977/10        0 12H20
  0021   18      151  1510/10        0
  0022   14      150  1149/10        0
  0023   11      151     0/10        0
  0024    8      141     0/10        0
  0025   11      151     0/10        0
  0026    9      150     0/10        0
  0027    7      140     0/10        0
  0028    6      123     0/10        0
  0029    9      151     0/10        0
  0030   13      150   821/10        0 12H30
  0031   14      151  1368/10        0
  0032   14      150   933/10        0
  0033    9      150     0/10        0
  0034    7      149     0/10        0
  0035    8      151     0/10        0
  0036    7      137     0/10        0
  0037    8      147     0/10        0
  0038   10      150     0/10        0
  0039   10      151     0/10        0
  0040   12      150     0/10        0 12H40
  0041   12      151     7/10        0
  0042   10      151     0/10        0
  0043    9      151     0/10        0
  0044   10      151     0/10        0
  0045    8      145     0/10        0
  0046   12      150     0/10        0
  0047   14      151   772/10        0
  0048   14      150   203/10        0
  0049   11      151     0/10        0
  0050   10      151     0/10        0 12H50
  0051    7      129     0/10        0
  0052   11      144     9/10        0
  0053   15      151  1207/10        0
  0054   10      132     0/10        0
  0055    9      151     0/10        0
  0056    8      136     0/10        0
  0057    7      126     1/10        0
  0058    9      145     0/10        0
  0059    6       44     0/10        0
  0060    0        0     0/00        0 13H00
  0061    0        0     0/00        0
  0062    0        0     0/00        0
  0063    0        0     0/00        0

CRC: 0xbecd
<<<<
 

At 13h05, I switch to 5975 kHz to try the multimedia
program, still on the ACER computer.

Later in the day, I resume testing with
the ACER computer here on 6140 DW... :

>>>>
Computer : ACER TravelMate 506T (Testing)
DRMSoftwareRadio-MERLIN-00000127
Software Version 1.0.21
Starttime (UTC)  2003-04-13 16:55:00
Frequency        6140 kHz
Latitude         44°49'N
Longitude         0°38'W

MINUTE  SNR     SYNC    AUDIO     TYPE
  0000   19       78   388/10        0 16H55
  0001   21       63   333/10        0
  0002   18       67   293/10        0
  0003   19       96   551/10        0
  0004   20       71   205/10        0
  0005   18       86   553/10        0 17H00
  0006   17       63   229/10        0
  0007   13       59   328/10        0
 

CRC: 0x306b
<<<<

The above is very poor. Actually the spectrum is
permanently alternating from acceptable SNR
to total loss of sync. This is not a "normal QRM"
situation where SNR is just decreasing for a while.
Suspecting computer/soundcard problem, I switch back to my
IBM desktop and find .. it works much better! (see below)

I will then notice that... the system time on the Acer
is... very late.   Actually loosing 7 seconds per minute
while decoding DRM !  Here I have my conclusion,
if the Acer computer seems OK to decode strong
Sines signal... it is not!
[Well I tried again 6140 on 19/04 and this time there was no
clock problem and the audio breaks seem to only come from
fading in signal level. So... will continue experiments.]

Below I return to my usual desktop... :
(TS440 + FM pickup point + FM mode, ant dipole 2x7m on
balcony + 5m coax cable + IBM Netvista A30P P4 1.8G
built-in soundcard).

Computer : IBM Netvista desktop