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VE2HAR > MT63     15.03.05 17:37l 128 Lines 3562 Bytes #-7297 (0) @ WW
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Subj: [MT63] Test Procedure
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Thanks to Patrick, F6IN, for bringing PathSim to our attention.  This is =
truly a
nice application.

Building on what I believe Tomi or others have said, as well as my own th=
oughts
about having a "test" file.  Also, looking at G4HPE's papers found at
http://www.rsgb.org/emergency/datamodesinfo.htm .  And not to be left out=
, my
several E-Mails with Charles, G4GUO.

Back in Jan/Feb of 1990, the US TRANSCON began "testing", on-the-air, HF
transmissions of  a file which became their standard.  It was a 40KB file=
.  The
modes being used were the MIL-STD-188-110 type.  These were interesting t=
est.=20
The MD5 sum was used on each received file to verify that its was the sam=
e as
the original file.  Throughput and accuracy were important.

G4HPE in his paper "A PRACTICAL EVALUATION AND COMPARISON OF SOME MODERN =
DATA
MODES" (http://www.rsgb.org/emergency/articles/datmodes2.pdf) Richard spe=
ak of
the test he did on MT63 and MFSK16.

Also, on page 17 of Rick=92s, KN6KB, presentation to the DCC last Septemb=
er
(2004), he shows throughput using an HF channel simulator from KC7WW=92s =
Oregon
Software Factory.

G4HPE=92s test concluded that MT63 had a throughput of 200 WPM at a =965 =
dB SNR on a
poor CCIR Channel.  KN6KB=94s results for Pactor II/III indicate a simila=
r (if not
lower) throughput under the same signal conditions.

While I do not doubt these findings, I believe that as some in this group=
 are
very technical, we need to develop a standard method of testing various n=
ew
modes under varying conditions using Moe Wheatley=92s, AE4JY, PathSim.

Here is my suggestion.

1)  Create/develop a standard file of at least 400 words (5 characters on=
e space
per word, 6 bytes =852.4KBPs).

2)  Generate this file in the mode to be tested and store it electronical=
ly on a
computer hard drive, CD or other magnetic storage media.

3)  =93Play=94 this file through the AE4JY=92s PathSim application at the=
 following HF
Simulation parameters:



        CCIR 520-2  Conditions		SRN (in dB)
	Good Conditions			+10	+5	0	-5
	Moderate Conditions		+10	+5	0	-5
	Poor Conditions			+10	+5	0	-5
	Flutter fading			+10	+5	0	-5
	Low-latitude quite		+10	+5	0	-5
	Low-latitude  disturbed		+10	+5	0	-5
	Mid-latitude quite		+10	+5	0	-5
	Mid-latitude  disturbed		+10	+5	0	-5
        High-latitude quite		+10	+5	0	-5
	High-latitude  disturbed	+10	+5	0	-5

4)  Record output or =93play=94 it through the mode detector and capture =
the output.


5)  With software techniques to manually determine the throughput at each=
 signal
condition.

6)  Document the results and provide the results to interested parties.

I realize that this  is just a rough draft of a testing process but think=
 its is
within the capability of a number of list members and the results might b=
e VERT
INTERESTING.

You comments solicited.

Thanks & 73,

Walt/K5YFW




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