This was posted on Mon 13 January 2003 on www.drmrx.org forum:
(more screenshots were added on the log pages)
 

I experimented my software for the first time this weekend. I will just
"describe" what I have seen or done. But I am not able to say what is
good or wrong, and if I describe a success or a failure. But I saw that
signal on my screen and heard it in my speakers, so, I had  fun anyway!
Sunday morning gave exciting results for some 45 minutes without a break.

The receiver & antenna:
Kenwood TS440SAT with narrow CW filters (well, not used here!)
Ant :  10 meters external wire connected to the coax cable
thru a zx-yagi adapter. No antenna tuning device at this time.
(room for improvement)

The mixer:
Crystal Mixer, fq=467kHz from Sat-Service Schneider.
(well, is anyone working on providing an amateur lowcost kit ...?)
For now I left  it as a separate outside box. Actually used the
black esd plastic box it comes in.

 I soldered:
- A 9 volts battery connector  (don't bother about using supply from
   receiver for now)
- A jack connector (20 cm shielded wire) on mixer output that allows to connect the
  standard jack cable (1,30 meter long) that goes to the microphone input
on the back of the computer. Don't even know if it's shielded on not.
- A cinch connector on the mixer input with a 50cm shilded wire that goes
towards the receiver. At this time it ends with two non shielded flying wires,
 one for the ground ("crocodile" somewhere on the receiver gnd), the other trying
 to get the IF signal from inside the receiver (also "crocodile" like).
The RX cover is removed, wide open for the tests. RX is very close to the
computer (10cm, under it).
(room for improvement in all the above).
Question : how critical is the quality of the wiring:
- from RX to mixer  ?
- from mixer to sound card ?

The computer:
IBM Netvista A30p Desktop, Pentium 4  1.8GHz, 256MB RAM
Windows 2000 5.0 SP2

The sound device:
Built-in audio device called  SoundMAX.
Didn't find any way to adjust AGC or to adjust anything.

Getting the IF signal:
I tried two options as seen somewhere in this forum:
- AM : connect to diode D14, on the left of the CFJ455K
  (giving a bad shape spectrum display, but got stable sound output
   at some time)- (file TS440-AM.jpg)

- FM : Pin 5 of the MC3357P actually not easy, so I connected
  to the upper side of resistor R124.  (file TS440-FM.jpg)
  (better signal shape - the right mode to use, it seems)

Sat 11 Jan 2003, 15440, 9h30-12h  DW Sines:
During the first hour, heard sound for a few seconds only, signal
spectrum was not good, nearly never sync'd, SNR very low or zero.
I found signal had good shape for a second or two at the start
only (switch on) , thus suspected some kind of AGC effect.
I then looked at that signal level indicator. Didn't know how to
read it. was never moving and always showing all colors...
Then I remembered there is a level adjustment on the mixer.
Bingo, I decreased the level, spectrum shape improved and...
program was heard in the speakers!

10h40: SNR 24dB - Starting the logging file.
10h45 level decreasing, I try to readjust on the mixer
10h49 some breaks
10h50 I try to change the IF pickup point to AM mode.
Need to increase the level on the mixer.
The spectrum has visually a bad shape because of filtering but
the sound is here, quite good , better than it was a minute
earlier on FM. SNR peaks to 26dB.
One break at 10h54, another at 10h55.

(photo11JA1102)
11h05 I change back to the FM pickup point, thus need to
decrease the level on the mixer.

(photo11JA1105)
11h12 some kind of signal fading . I readjust mixer level.

(photo11JA1123)
11h30 I try 9780 kHz.  Nothing on spectrum display.
11h31 back to 15440.  SNR 21dB

(photo11JA1139)
Good signal receipt until signoff at 12h00. SNR 18 to 24dB

(photo11JA1152)

After some search, I find the log file is named DRMSoftwareRadio.txt.
(see log-file11J15440.html)

Sat 11 Jan 2003, 5975,  13h05-14h55, multimedia Juelich
Starting the logfile at 13h00.
Did not suspect any signal until 13h35.

13h35 changed to AM just to try and got a SYNC and DATA for
a few seconds, discovering there must be a broadcast going on.
(photo11JA1527)

Changed back to FM and monitored until 14h45.
No signal most of the time. On exception, for a few seconds,
SNR peaks to 5/7dB allowing a SYNC and then DATA.
The 4 multimedia services (names) appeared on the screen.
Could launch the multimedia player but never got data
(got the service switching menu). Never got audio.

Note: After launching the multimedia player, got error message
"the connexion was refused when attempting to connect 127.0.0.1:42813".
(I have no internet on the machine). I did the dummy proxy setup as
indicated in the manual. Seems it didn't reoccure since then.

Sunday 12 Jan 2003, 15440kHz, 9h30-12h, DW Sines
See the full logging  file 12J15440.html
- 100% audio receipt from 9h41 to 10h30
  (one single half-a-second break only at 10h19)
- During the above, the TS440 signal meter stays at S9+50db (fm mode..)
- Then there were breaks in the signal (see file) corresponding most of the
  time to drops in the signal level on the S-meter causing SNR drops.
- At the end, SNR drop is caused by fast QSB, although the signal level
stays within correct limits.

Sunday 12 Jan 2003, 5975kHz, 13h05-14h55, multimedia Juelich
Listening from 13h, no signal suspected either on spectrum, s-meter
of FM audio noise.
Sync and data appeared for a few seconds only at 13h32 and then 13h36.
(photo 12JA1332)
(log file 12J5975.html)

Sunday 12 Jan 2003, 11755kHz, 21h30-22h30 UTC
I monitored the full hour. No sign of any signal at all.
RX S-meter stayed at Zero. Frequency quiet  (well, whole band too).
 

Final questions :
- Does my sound card seem suitable or not ?
The answer was yes, because it was able to receive
properly in full duplex for some long time.
- Does my IF picking point in the TS440  seem suitable or not ?
seems not too bad
- Which area would you improve next ?
maybe some adjustments in the receiver circuit could
improve the S/N ratio.
Best 73's
 
 
 

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