[digitalradio] NZ4O Radiowave Propagation Forecast #2010-04

2010-01-22 Thread Thomas F. Giella NZ4O
The NZ4O Daily LF/MF/HF/6M Frequency Radiowave Propagation Forecast #2010-04
has been published on Friday 01/22/2009 at 1000 UTC, valid  UTC Saturday
01/23/2010 through 2359 UTC Friday 01/23/2009 at http://www.solarcycle24.org 
.

73  GUD DX,
Thomas F. Giella, NZ4O
Lakeland, FL, USA
n...@arrl.net

LF/MF/HF/VHF/UHF Frequency Radiowave Propagation Email Reflector:
http://lists.contesting.com/mailman/listinfo/spaceweather
NZ4O Daily Solar Space Weather  Geomagnetic Data Archive:
http://www.solarcycle24.org
NZ4O Solar Space Weather  Geomagnetic Data In Graphic  Image Format:
http://www.wcflunatall.com/nz4o2.htm
NZ4O Daily LF/MF/HF/6M Frequency Radiowave Propagation Forecast  Archive:
http://www.wcflunatall.com/nz4o3.htm
NZ4O Solar Cycle 24 Forecast Discussion  Archive:
http://www.wcflunatall.com/nz4o4.htm
NZ4O 160 Meter Radio Propagation Theory Notes:
http://www.wcflunatall.com/nz4o5.htm
NZ4O Solar Space Weather  Geomagnetic Raw Forecast Data Links:
http://www.wcflunatall.com/nz4o6.htm
Harmful Man Induced Climate Change (Global Warming) Refuted:
http://www.globalwarminglie.htm





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[digitalradio] Re: Comparison of RTTY software sensitivity

2010-01-22 Thread Vojtech
Here is another, similar chart:
http://www.dxatlas.com/RttyCompare/

I was comparing MMTTY with MultiPSK and gMFSK against RTTY in white noise. 
Interesting observation was that MMTTY was better than MultiPSK at better than 
marginal SNR, but MultiPSK was slightly better than MMTTY at very low SNR. My 
best bet is that MMTTY is doing some kind of signal processing after detector, 
which fixes some errors, but makes things worse in very low SNR.

Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I wonder 
whether TrueRTTY is doing synchronous detection. This is what I plan to try 
when I retire, hi.

73, Vojtech OK1IAK




Re: [digitalradio] Re: Comparison of RTTY software sensitivity

2010-01-22 Thread Wes Cosand


 Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I
 wonder whether TrueRTTY is doing synchronous detection. This is what I plan
 to try when I retire, hi.

 73, Vojtech OK1IAK


TrueTTY also gave results better than any other package tested for MFSK16.

Wes, WZ7I


[digitalradio] TrueTTY

2010-01-22 Thread Andy obrien
On Fri, Jan 22, 2010 at 8:00 AM, Wes Cosand wes.cos...@gmail.com wrote:



 Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I wonder 
 whether TrueRTTY is doing synchronous detection. This is what I plan to try 
 when I retire, hi.

 73, Vojtech OK1IAK


 TrueTTY also gave results better than any other package tested for MFSK16.

 Wes, WZ7I
 



Interesting.  I have not used that software in a long time.  Are many
people using it ?

Andy K3UK


Re: [digitalradio] TrueTTY

2010-01-22 Thread Wes Cosand
On Fri, Jan 22, 2010 at 8:17 AM, Andy obrien k3uka...@gmail.com wrote:



 On Fri, Jan 22, 2010 at 8:00 AM, Wes Cosand 
 wes.cos...@gmail.comwes.cosand%40gmail.com
 wrote:
 
 
 
  Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I
 wonder whether TrueRTTY is doing synchronous detection. This is what I plan
 to try when I retire, hi.
 
  73, Vojtech OK1IAK
 
 
  TrueTTY also gave results better than any other package tested for
 MFSK16.
 
  Wes, WZ7I
 

 Interesting. I have not used that software in a long time. Are many
 people using it ?

 Andy K3UK

I haven't heard people using it on the air much but I am registering a copy
this morning.  It's performance on MFSK is amazing.

Wes, WZ7I


Re: [digitalradio] TrueTTY

2010-01-22 Thread VE3FAL-Fred
I have had a registered copy for about 8 years now and love the program, 
absolutely worth it..

Fred
VE3FAL

On Fri, 22 Jan 2010 08:32:06 -0500
  Wes Cosand wes.cos...@gmail.com wrote:
 On Fri, Jan 22, 2010 at 8:17 AM, Andy obrien k3uka...@gmail.com wrote:
 


 On Fri, Jan 22, 2010 at 8:00 AM, Wes Cosand 
wes.cos...@gmail.comwes.cosand%40gmail.com
 wrote:
 
 
 
  Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I
 wonder whether TrueRTTY is doing synchronous detection. This is what I plan
 to try when I retire, hi.
 
  73, Vojtech OK1IAK
 
 
  TrueTTY also gave results better than any other package tested for
 MFSK16.
 
  Wes, WZ7I
 

 Interesting. I have not used that software in a long time. Are many
 people using it ?

 Andy K3UK

 I haven't heard people using it on the air much but I am registering a copy
 this morning.  It's performance on MFSK is amazing.
 
 Wes, WZ7I



[digitalradio] Re: Comparison of RTTY software sensitivity

2010-01-22 Thread jhaynesatalumni


--- In digitalradio@yahoogroups.com, Vojtech bubn...@... wrote:
 
 Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I wonder 
 whether TrueRTTY is doing synchronous detection. This is what I plan to try 
 when I retire, hi.
 

There used to be the K6STI RITTY program which does synchronous
detection.  I wish we had a comparison of it with some of the
modern RTTY software.  Trouble is, RITTY requires a DOS
environment and a SoundBlaster ISA sound card, and you don't
find those much anymore.  And it's no longer on the market.

I was really excited when it came out, because I had wanted to do
synchronous detection for a long time.  However it didn't appear
to be all that helpful, maybe a db or two.

Then PSK31 for the sound card modem came out and most of the 
rag chewers switched to that from RTTY.

Jim W6JVE



[digitalradio] Re: Comparison of RTTY software sensitivity

2010-01-22 Thread jhaynesatalumni
Now I don't know about TrueTTY, but MMTTY has a number of things
you can play with in terms of the filtering and detection, so I
wonder if we could get some comparisons of those - or at least
tell us what the setup was when it was tested.

Jim W6JVE




[digitalradio] Comparison of MFSK16 software sensitivity

2010-01-22 Thread Wes Cosand
Folk:

I have conducted an experiment comparing the sensitivity of several software
programs for MFSK16 similar to those just posted for RTTY.  The data in the
MFSK16 tests were a little tighter than in the RTTY experiment, presumably
because of the absence of the profound effect of stochastic figures/letters
shifts.

I am a little torn about posting these data because I am hesitant to use any
program for transmitting MFSK16 that does not incorporate Patrick's RSID
function.  I have been working hams for whom I am their first MFSK16 QSO and
it is usually because they are running one of the packages that has RSID.

The data is at http://mysite.verizon.net/wz7i/MFSK16.html

Once again, I would welcome comments about how the testing could be
improved.

Wes, WZ7I
www.wz7i.com


Re: [digitalradio] Comparison of MFSK16 software sensitivity

2010-01-22 Thread Phil Williams
I am their first MFSK16 QSO and it is usually because they are running one
of the packages that has RSID

This has been my experience too.  I operate THOR4 and Contestia.   Most
first time QSOs are with the aid of RSID.

philw de ka1gmn


On Fri, Jan 22, 2010 at 11:49 AM, Wes Cosand wes.cos...@gmail.com wrote:



 Folk:

 I have conducted an experiment comparing the sensitivity of several
 software programs for MFSK16 similar to those just posted for RTTY.  The
 data in the MFSK16 tests were a little tighter than in the RTTY experiment,
 presumably because of the absence of the profound effect of stochastic
 figures/letters shifts.

 I am a little torn about posting these data because I am hesitant to use
 any program for transmitting MFSK16 that does not incorporate Patrick's RSID
 function.  I have been working hams for whom I am their first MFSK16 QSO and
 it is usually because they are running one of the packages that has RSID.

 The data is at http://mysite.verizon.net/wz7i/MFSK16.html

 Once again, I would welcome comments about how the testing could be
 improved.

 Wes, WZ7I
 www.wz7i.com
  



[digitalradio] Re: TrueTTY

2010-01-22 Thread sholtofish
Andy,

I have had a registered copy of TruTTY for years and it constantly outperforms 
any other program for RTTY. I also think the MFSK-16 and PSK31 implementations 
are excellent too. Well worth the money if you need a simple to operate, 
processor non-intensive application. It also interfaces to AALog3 which makes 
it very useful.

For those interested in SW monitoring the SeaTTY program also has excellent 
performance on Navtex, GMDSS and HF fax.

Patrick's MultiPSK fax decoding is slightly better I think but the automatic 
logging facility of SeaTTY is fantastic.

For weak signal Morse then Norbert's MRP40 is unrivaled. If you've never tried 
this program then download the demo and try it.

Sholto
K7TMG



[digitalradio] PSK/ digital mode SDR software ?

2010-01-22 Thread Andy obrien
My shack PC has some resource  issues when using the only software
that I know of that has some digital mode SDR support, Multipsk.  This
is because it requires Multipsk AND a SDR software to be used in
tandem.  The TWO applications are more than my system can handle.  I
do have CW Skimmer that does NOT require an additional application,
thus it runs within my PC''s capabilities,  While I try to free up an
better computer, I wonder if there are any existing SDR applications
that DIRECTLY  support digital modes ?  Something the equivalent of CW
Skimmer for digital modes, where you just press start and the SDR is
activated and digital mode decoding occurs  ?

Andy K3UK


RE: [digitalradio] Re: Comparison of RTTY software sensitivity

2010-01-22 Thread Dave AA6YQ
MMTTY provides a choice of three different RTTY decoders, with the ability
to shape the filters for each. There is also an optional bandpass filter and
an optional notch filter, with user control of shape for each.  As a first
step in improving MMTTY's RTTY decoding performance, I am determining how to
optimize performance given the capabilities Mako-san JE3HHT has already
provided, using a setup similar to what Alex VE3NEA and Wes WZ7I  have used.

 

Note that on the chart Wes posted, WinWarbler running the HyperSensitive
profile with both the bandpass and notch filters enabled yields sensitivity
close to that of TrueTTY. WinWarbler uses MMTTY as its RTTY engine, so this
performance is possible with MMTTY alone.

 

By synchronous detection, Vojtech, do you mean treating the first start bit
as the beginning of a synchronous multi-character sequence, thereby
providing some protection against broken start and stop bits within that
sequence? Brian K6STI referred to his decoding technique as employing a
flywheel, which I interpreted as a means of adjusting the synchronous
timing with high-quality start bits decoded within the sequence.

 

73,

 

 Dave, AA6YQ

 

 

From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On
Behalf Of Vojtech
Sent: Friday, January 22, 2010 8:27 AM
To: digitalradio@yahoogroups.com
Subject: [digitalradio] Re: Comparison of RTTY software sensitivity

 

  

Here is another, similar chart:
http://www.dxatlas.com/RttyCompare/

I was comparing MMTTY with MultiPSK and gMFSK against RTTY in white noise.
Interesting observation was that MMTTY was better than MultiPSK at better
than marginal SNR, but MultiPSK was slightly better than MMTTY at very low
SNR. My best bet is that MMTTY is doing some kind of signal processing after
detector, which fixes some errors, but makes things worse in very low SNR.

Both yours and Alex's graphs show superiority of TrueRTTY and MixW. I wonder
whether TrueRTTY is doing synchronous detection. This is what I plan to try
when I retire, hi.

73, Vojtech OK1IAK



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15:34:00



[digitalradio] Comparison of RTTY software sensitivity - New tests

2010-01-22 Thread Patrick Lindecker
Hello Wes and all,

I tried here Multipsk versus Mixw at -9 dB of S/N in RTTY 45 (I have not 
TRUETTY but they seem to be equivalent).

I tested with a text and the Multipsk decoding was better than the Mixw one . 
However, in RTTY the ITA2 set of character is used so it is difficult to 
compare because figures instead of letters can be seen as bad whereas there are 
good in fact (simply due to a random switching) .
So I tested with C8C8C8C8C8C8C8C8C8C8 to avoid not this problem. I confirmed 
that the Multipsk RTTY decoding is better than the Mixw one (I don't think to 
have a partial opinion, I hope so...).

But Multipsk could work better on this particular characters, so I tried with 
1A2B3C4D5E6F7G8H9...which is a diversified sequence.

I got 135 characters OK with Multipsk and 107 on Mixw. 

In both softs, I set the AFC Off and I tested with a confortable level (about 
40 % of the maximum in average, taken on the Multipsk level), same exact AF 
frequency (830/1000 Hz).

Note 1: I used a sound blaster sound card to send the signal which was decoded 
by both softs (input plugged with the output).

Note 2: the decoding on Multipsk and Mixw is almost perfect (only few errors) 
at about -5.5 dB.

73
Patrick
  
  - Original Message - 
  From: Wes Cosand 
  To: digitalradio@yahoogroups.com 
  Sent: Thursday, January 21, 2010 3:05 AM
  Subject: Re: [digitalradio] Comparison of RTTY software sensitivity






  On Wed, Jan 20, 2010 at 8:06 PM, Dave AA6YQ aa...@ambersoft.com wrote:

  

Thanks Wes.



WinWarbler uses MMTTY as its RTTY engine; thus MMTTY can be configured to 
achieve the same performance as that shown for WinWarbler.

  Yes, I certainly did not mean to construct a test to show MMTTY at a 
disadvantage.  I assumed folk would realize that the engine is the same in the 
two packages.

  I wanted to see if there was a difference between the Hyper Sensitive profile 
(which exists as a predefined profile only in WinWarbler) and the Standard 
profile which is the default in both packages.  

  I was surprised after the tests to see the significant difference in 
performance made by inserting the notch filter between the mark and space 
frequencies.

  TrueTTY would seem to deserve wider attention.  I have used UA9OV's CW Get 
for a number of years to zero beat my CW and perhaps I should keep a copy his 
TrueTTY running as a second receive modem when I work RTTY. 

  Wes, WZ7I




  

Re: [digitalradio] PSK/ digital mode SDR software ?

2010-01-22 Thread Patrick Lindecker
Andy,

 is because it requires Multipsk AND a SDR software to be used in
Multipsk works alone on SdR (RX/TX). You don't need another SdR (and surely 
it would be a mess to work with two SdR programs doing the same thing). 
Simply, indicate in Multipsk which sound card (or sound cards if a speaker 
is added) to work. That's all.

73
Patrick


- Original Message - 
From: Andy obrien k3uka...@gmail.com
To: digitalradio digitalradio@yahoogroups.com
Sent: Friday, January 22, 2010 10:58 PM
Subject: [digitalradio] PSK/ digital mode SDR software ?


 My shack PC has some resource  issues when using the only software
 that I know of that has some digital mode SDR support, Multipsk.  This
 is because it requires Multipsk AND a SDR software to be used in
 tandem.  The TWO applications are more than my system can handle.  I
 do have CW Skimmer that does NOT require an additional application,
 thus it runs within my PC''s capabilities,  While I try to free up an
 better computer, I wonder if there are any existing SDR applications
 that DIRECTLY  support digital modes ?  Something the equivalent of CW
 Skimmer for digital modes, where you just press start and the SDR is
 activated and digital mode decoding occurs  ?

 Andy K3UK


 

 Suggested frequencies for calling CQ with experimental digital modes =
 3584,10147, 14074 USB on your dial plus 1000Hz on waterfall.

 Announce your digital presence via our Interactive Sked Pages at
 http://www.obriensweb.com/sked
 Yahoo! Groups Links




 




Re: [digitalradio] PSK/ digital mode SDR software ?

2010-01-22 Thread Andy obrien
I'm sorry I don't understand Patrick.  How do you start the SDR's
reception in Multipsk ?  The SDR I have is not playing audio until usual SDR
software starts the receiver  and audio flows .  I do not see that in
Multipsk ?

Andy K3UK


On Fri, Jan 22, 2010 at 6:12 PM, Patrick Lindecker f6...@free.fr wrote:



 Andy,


  is because it requires Multipsk AND a SDR software to be used in
 Multipsk works alone on SdR (RX/TX). You don't need another SdR (and surely

 it would be a mess to work with two SdR programs doing the same thing).
 Simply, indicate in Multipsk which sound card (or sound cards if a speaker
 is added) to work. That's all.

 73
 Patrick


 - Original Message -
 From: Andy obrien k3uka...@gmail.com k3ukandy%40gmail.com
 To: digitalradio 
 digitalradio@yahoogroups.comdigitalradio%40yahoogroups.com
 
 Sent: Friday, January 22, 2010 10:58 PM
 Subject: [digitalradio] PSK/ digital mode SDR software ?

  My shack PC has some resource issues when using the only software
  that I know of that has some digital mode SDR support, Multipsk. This
  is because it requires Multipsk AND a SDR software to be used in
  tandem. The TWO applications are more than my system can handle. I
  do have CW Skimmer that does NOT require an additional application,
  thus it runs within my PC''s capabilities, While I try to free up an
  better computer, I wonder if there are any existing SDR applications
  that DIRECTLY support digital modes ? Something the equivalent of CW
  Skimmer for digital modes, where you just press start and the SDR is
  activated and digital mode decoding occurs ?
 
  Andy K3UK
 
 
  
 
  Suggested frequencies for calling CQ with experimental digital modes =
  3584,10147, 14074 USB on your dial plus 1000Hz on waterfall.
 
  Announce your digital presence via our Interactive Sked Pages at
  http://www.obriensweb.com/sked
  Yahoo! Groups Links
 
 
 
 
 

  



Re: [digitalradio] PSK/ digital mode SDR software ?

2010-01-22 Thread Patrick Lindecker
Andy,

By default, for digital RX/TX, you don't strictly need to hear the sound. When 
you pushed on I/Q interface Direct  via the sound card, you could RX/TX just 
selecting the desired signal on the waterfall.  Now if you want to hear the 
received sound (the base band demodulated one, not the SdR one), push on 
+Speaker and select the Auxiliary Sound card (to Speaker).

You need a second sound card for this:
* a SWL could use the same sound card to RX SdR and listen to the demodulated 
sound,
* as a Ham, you must use a first (good) sound card to RX/TX and a second one 
(standard) to listen to the demodulated sound.

73
Patrick
  - Original Message - 
  From: Andy obrien 
  To: digitalradio@yahoogroups.com 
  Sent: Saturday, January 23, 2010 12:13 AM
  Subject: Re: [digitalradio] PSK/ digital mode SDR software ?




  I'm sorry I don't understand Patrick.  How do you start the SDR's reception 
in Multipsk ?  The SDR I have is not playing audio until usual SDR software 
starts the receiver  and audio flows .  I do not see that in Multipsk ?

  Andy K3UK



  On Fri, Jan 22, 2010 at 6:12 PM, Patrick Lindecker f6...@free.fr wrote:

  
Andy,



 is because it requires Multipsk AND a SDR software to be used in

Multipsk works alone on SdR (RX/TX). You don't need another SdR (and surely 
it would be a mess to work with two SdR programs doing the same thing). 
Simply, indicate in Multipsk which sound card (or sound cards if a speaker 
is added) to work. That's all.

73
Patrick


- Original Message - 
From: Andy obrien k3uka...@gmail.com
To: digitalradio digitalradio@yahoogroups.com
Sent: Friday, January 22, 2010 10:58 PM
Subject: [digitalradio] PSK/ digital mode SDR software ?

 My shack PC has some resource issues when using the only software
 that I know of that has some digital mode SDR support, Multipsk. This
 is because it requires Multipsk AND a SDR software to be used in
 tandem. The TWO applications are more than my system can handle. I
 do have CW Skimmer that does NOT require an additional application,
 thus it runs within my PC''s capabilities, While I try to free up an
 better computer, I wonder if there are any existing SDR applications
 that DIRECTLY support digital modes ? Something the equivalent of CW
 Skimmer for digital modes, where you just press start and the SDR is
 activated and digital mode decoding occurs ?

 Andy K3UK



 

 Suggested frequencies for calling CQ with experimental digital modes =
 3584,10147, 14074 USB on your dial plus 1000Hz on waterfall.

 Announce your digital presence via our Interactive Sked Pages at
 http://www.obriensweb.com/sked
 Yahoo! Groups Links




 






  

Re: [digitalradio] Comparison of RTTY software sensitivity - New tests

2010-01-22 Thread Wes Cosand
Patrick, thank you for your kind note.

I discovered, as you have known for a long time, that testing RTTY is not
easy because of random figures/letters shifts.  As you said, a single
inappropriate shift can mess up a lot of characters!  That makes the
statistics difficult.

My test text file is at
http://mysite.verizon.net/wz7i/Text%20file%20for%20testing%20communications%20software.html

I used call signs and about 30% five number groups to try to deal with this
issue.  I tested with UOS off because of the number groups.  It may be that
I should have used a shorter file and then tested it with different audio
files a number of times to get reasonable statistics but that seemed too
much work... chuckle...  The error bars on the graph might have been
significant.  Instead I tried to run a long enough text file to average out
all the random shifts.  It probably wasn't long enough to try to analyze the
data too closely.

I, too, tested with AFC off.  I used the audio frequencies used for FSK so
that is a difference.  Our audio levels were about the same -- 40% sounds
about right.

As I said earlier, it is possible that I have incorporated some error in my
methods.  It is possible that I am straining at gnats and swallowing
camels   :-)

Thank you for your patience with me.

73 de Wes, WZ7I


AW: [digitalradio] Digital modes with an SDR ?

2010-01-22 Thread Siegfried Jackstien
Dear Andy

What sdr and what trx are you using?

I use a icom 765 with a homebrewd downconverter … not a real sdr but I can
use the software that is built for if of 12khz

And it is possible to connect powersdr with hrd to control the trx

A friend from me did this with his kenwood ts2000 (no downmixer needed cause
last if is 12khz)

73´s dg9bfc

sigi

 

  _  

Von: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] Im
Auftrag von Andy obrien
Gesendet: Dienstag, 19. Januar 2010 05:04
An: digitalradio
Betreff: [digitalradio] Digital modes with an SDR ?

 

  

My SDR receiver is due to be delivered tomorrow. I am looking
forward to using a wide band panadapter for receive and having my
transceiver sync'd for ability to transmit when desired. Since I
vacillate between CW and digital modes , I will enjoy keeping an eye
on both portions of a band at the same time. I am also looking
forward to trying Multipsk with is SDR capabilities and RS ID
combination. I assume there are many others with SDR transceivers or
receivers here in this group, and wonder how you are using it for
digital modes ?

Andy K3UK





Re: [digitalradio] Comparison of RTTY software sensitivity - New tests

2010-01-22 Thread Patrick Lindecker
Hello Wes,

I saw the test file. It is nice except the long suite of figures, which could 
be a cause of possible systematic failure (with many errors following a first 
error) . Better would be to keep only the call signs which include figures and 
letters and produce a good diversity (and so a more precise statistic result).

Also it would be perhaps interesting to transmit the RTTY characters through 2 
different programs because a program could produce a not exactly nominal RTTY 
transmission and its decoding could match this transmission (for example, the 
stop must be 1.5 bits but can vary in fact). If, with two different 
transmissions, the results are the same, they can be considered as reliable.
 
73
Patrick


  - Original Message - 
  From: Wes Cosand 
  To: digitalradio@yahoogroups.com 
  Sent: Saturday, January 23, 2010 12:42 AM
  Subject: Re: [digitalradio] Comparison of RTTY software sensitivity - New 
tests




  Patrick, thank you for your kind note.

  I discovered, as you have known for a long time, that testing RTTY is not 
easy because of random figures/letters shifts.  As you said, a single 
inappropriate shift can mess up a lot of characters!  That makes the statistics 
difficult. 

  My test text file is at 
  
http://mysite.verizon.net/wz7i/Text%20file%20for%20testing%20communications%20software.html

  I used call signs and about 30% five number groups to try to deal with this 
issue.  I tested with UOS off because of the number groups.  It may be that I 
should have used a shorter file and then tested it with different audio files a 
number of times to get reasonable statistics but that seemed too much work... 
chuckle...  The error bars on the graph might have been significant.  Instead I 
tried to run a long enough text file to average out all the random shifts.  It 
probably wasn't long enough to try to analyze the data too closely. 

  I, too, tested with AFC off.  I used the audio frequencies used for FSK so 
that is a difference.  Our audio levels were about the same -- 40% sounds about 
right.  

  As I said earlier, it is possible that I have incorporated some error in my 
methods.  It is possible that I am straining at gnats and swallowing camels   
:-)

  Thank you for your patience with me.

  73 de Wes, WZ7I



  

Re: [digitalradio] Comparison of RTTY software sensitivity - New tests

2010-01-22 Thread Wes Cosand
On Fri, Jan 22, 2010 at 7:44 PM, Patrick Lindecker f6...@free.fr wrote:



 Hello Wes,

 I saw the test file. It is nice except the long suite of figures, which
 could be a cause of possible systematic failure (with many errors following
 a first error) . Better would be to keep only the call signs which include
 figures and letters and produce a good diversity (and so a more precise
 statistic result).

 Also it would be perhaps interesting to transmit the RTTY characters
 through 2 different programs because a program could produce a not exactly
 nominal RTTY transmission and its decoding could match this transmission
 (for example, the stop must be 1.5 bits but can vary in fact). If, with two
 different transmissions, the results are the same, they can be considered
 as reliable.

 73
 Patrick


Good suggestions, Patrick.  I will get it done.

But first I must go to a birthday party for my 6 year old Grandson!  I have
to have my priorities right... HI HI

Wes, WZ7I