Patrick, 

The sound card was already calibrated, but the offsets were not locked. Locking 
them seems to have made a difference. I repeated the same tests and decoding 
did improve with Multipsk (see below). 

As for one program having an advantage over another, I guess it could be due to 
the slight sensitivity advantage Nino's program seems to have. Minimum SNR 
(errorr-free throughput) is -8db for IZ8BLY and -6db for Mutlipsk. 

This seems to show-up in test #1 where the selective fading may be causing the 
signal to dip below the -6db decode threshold for Multipsk. Nino's software has 
a 2db "buffer" with this test. 

In test #3 where there's selective fading and lightning static, things improve 
with Multipsk when the SNR is inceased to +3db from -3db: 

Multipsk Test #3 

SNR +3db
THE QUIK BROW FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BRWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG


SNR -3db

HE QUIK3,ROWS F'XexMn OVER THE L/ZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY D+G
THE QUICK BRWg FOX JMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

Thanks for all Patrick. 

Tony, K2MO


++++++++++++++++++++++++++++++++++++++++++++++++++    

Test #1: SNR -6db selective fading 


IZ8BLY

TH; QUICK BAOWN FOX JUOPS OVrR THE LAZY [OG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWNFOX JUMPS OVER THE LAZY DOG

MixW

2Hx QU/8qvB,4YNn}mGbSI*+OenJX|Y aO|
TH3N$aaK RptNWFOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUIcK BROWN FOXFJUmPS "VER THE LAZY DOG

Multipsk

THN QUICKFB;OW ZX JP OVXR THErL,ZY RG
THE [UICK BROW FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

________________________________________________


Test #2: SNR -3db selective fading 


IZ8BLY

THE QUICK BROWN FOX JUOPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

MixW

THE AUICKROWN F:X JUMPS ,VER THE L/ZY [OG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

Multipsk

THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

_______________________________________________

Test #3: SNR -3db selective fading / lightning static 

IZ8BLY

THE QUCIK BROWq FOX JUMPS OVrR THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

MixW

THH mUICK0I\OWm iZM JUMPS ,VER THE 2AZYzDOG
THE QUICK BROWN FOX xUMPS OVER THE LAZY DOG
THE QUICK BRO9N FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

Multipsk

HE QUIK3,ROWS F'XexMn OVER THE L/ZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY D+G
THE QUICK BRWg FOX JMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

___________________________________________________

Test #4 SNR -9db

IZ8BLY
TH QUICK BROWN FOX_UMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

MixW
UHE qU4C? BROWN 9GX'JUMPS OVE THE LAZY DOG
THE QUI^d BnCWNlFOX JUMPS OVERDTHE LAZY OGj
HEs%#IC BRWN FOX JUMS OV5R THE LAZYBDOG
THE QrCK BROWN FBX UXPS OVER {HE"LAZpHDOG

Multipsk

TH\ QUIF,RO\[ F(U'xM
S OV:R THE LAZY DOG
THE QUICKBRON FOX JUMPS OVER THE LAZY DOG
THE QUICK BRKWN FO { MPS OVER THE LAZY DOG
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG






----- Original Message ----- 
From: "Patrick Lindecker" <[EMAIL PROTECTED]>
To: <digitalradio@yahoogroups.com>
Sent: Friday, September 26, 2008 7:04 PM
Subject: Re: [digitalradio] MT63 -- Mutlipsk, IZ8BLY, MixW


Hello Tony,

About Multipsk, could you first (if not done) the MT63 sampling calibration by 
clicking on "Sampling freq." and start the automatic calibration.

Note: in Multipsk there is a double correction:
* determination of the sampling frequency offset between the TX and the RX 
sound cards. This function does not belong to the original soft nor Mixw,
* determination of the frequency offset.

If you do a comparizon, click on the first "lock" to 0 (to avoid the 
determination of the sampling frequency offset, function which needs a good 
MT63 signal).

However, the original soft could be much better (I wrote an independant MT63 
decoding code and I don't know the way the original soft decodes).  

73
Patrick

  ----- Original Message ----- 
  From: Tony 
  To: digitalradio@yahoogroups.com 
  Sent: Saturday, September 27, 2008 12:35 AM
  Subject: [digitalradio] MT63 -- Mutlipsk, IZ8BLY, MixW


  All, 

  There seems to be some difference between Mutlipsk, MixW and IZ8BLY's 
software when it comes to decoding MT63. I ran all three programs 
simultaneously with a path simulator in line and the SNR set above the decode 
threshold. 

  The results were the same whether I ran the programs one at a time or 
simultaneously. Not sure why this is; would appreciate it if someone can shed 
some light on this. I plan to run each program on-the-air to see if the results 
change. 

  Tony, K2MO



  Test #1: SNR -6db selective fading 
  Test #2: SNR -3db selective fading 
  Test #3: SNR -3db selective fading / lightning static


  Test #1

  IZ8BLY MT63 Terminal
  TH QUICK BRAOWN FOX JUOPS OVER THE LAZY [OG
  THE QUICK BROWN FOX JUMPSOVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWNFOX JUMPS OVER THE LAZY DOG

  MixW 
  TH QUI4 M)9"Nd3/ANjV (UT$ExLZY UG
  THE QUICK BRmWN 1OX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUI>K BROWN F9XFJUmPS "VER THE LAZY DOG

  Multipsk 
  YhlU+ O~^ FlX JUiPSkOVER THE LAZY DOG
  THE QUICK{BOovFV!D.M]y5xVr| +v75UX7ØOpL{
  z]p?Bx~i6GzV$cSNVDcTH: LØZY DOG]mOT*

  _________________________________________________

  Test #2

  MT63 Terminal
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG


  MixW
  THF QUIaK BRORNdFOX J$MPS ?[7@ TWE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

  Multipsk
  THE QUICK BROWN FOX JM8; O5Es HE LAZY DG
  THe*QICK BROWN F+X JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

  ______________________________________________________

  Test #3

  IZ8BLY MT63 TERMINAL
  RON FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

  MIXW
  HE QUIAn BROWtF?X:J+MPS v)rR TE L/ZY DOG
  THE QUICK BRKWN FOX JUMPS OVER THE LAZY DOG
  THE QUICK BRO9  FOX JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG

  MULTIPSK
  $Xiu(L Kka?SO?m)#-ap^jtOu{+^d4,-`Ø$P{&&8YAZY O)
  ,njl'KuBRja "_J(/S VØRU!H5N(1=YDOG
  THE QUIkK B}O9g OY4JUMPS OVER THE LAZY DOG
  THE QUICK BROWN FOX JUMPS OVER THE LAZYØDOG

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