RTTY
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Re: [RTTY] RTTY

To: "RTTY Contesting" <rtty@contesting.com>, "Writelog Reflector" <writelog@contesting.com>
Subject: Re: [RTTY] RTTY
From: "Gary AL9A" <al9a@mtaonline.net>
Date: Mon, 21 Mar 2011 12:21:31 -0800
List-post: <rtty@contesting.com">mailto:rtty@contesting.com>
Wow, there sure are a bunch of guys out there with answers!  I omitted one 
thing from my RTTY setup, but that didn't stop the correct answer from 
coming through anyway.  In addition to WriteLog and MMTTY I also have the 
microHAM MicroKeyer II that sends my RTTY.  Phil, GU0SUP wins the first 
place prize for being fastest on the draw with the correct answer.  Second 
place goes to John, WA5ZUP.  The first place prize is a big steaming bowl of 
Alaskan Fish Head Soup!  Second place is two bowls!

Both Phil and John suggested unchecking the "strict bps" box on the Ports 
tab in the microHAM router software.  I did that and just by ear I notice a 
significant increase in my RTTY sending speed!  Of course it would have 
helped if I had actually reread the help manual for the MK II  where it 
states:

"NOTE: DO NOT select Strict bps for MMTTY, USB option C provides accurate 
timing."

Apparently in making my original router configurations I missed this verbage 
in the text and went with the screen shot that showed the "strict bps" box 
checked.  The Help manual also explains the reason for this check box.

"Some programs rely on the the UART "buffer full" signal for proper PTT 
timing and drop PTT (unkey) when the UART buffer is empty. Because virtual 
ports generally have two buffers - one in the USB driver and one in the 
hardware - the first buffer may empty before all of the data has been 
transmitted allowing the PTT to (drop) before the message is complete. 
'Strict bps' disables the USB buffering and sends one character at a time to 
the FSK output. With "Strict BPS" selected, the output will be about 20% 
slower due to the presence of extra stop bits between characters but proper 
PTT operation will be assured."

So both Hank, W6SX and John, WA5ZUP noticed the 20% drop in speed by ear!  I 
just did a quick check with a stop watch.  When I send a test BARTG exchange 
with strict bps enabled it takes 10:44 secs.  Sending the same exhange with 
strict bps disabled takes only 9:16 seconds.  That's 1:28 seconds faster on 
the same exchange info!

Incidentially, thanks also to Kok for his comments regarding the stop bits 
and character spacing.  I checked MMTTY and on the Decode tab the StopLength 
item selected is "Rx=1bit, Tx=1.5bit".  I changed this to "1bit" and tried 
the same test exchange - 8:68 seconds!  My exchange was set up with spaces 
between the elements as "RST NR TIME NR TIME.  I changed that to have a "-" 
in between the elements so that now it is RST-NR-TIME-NR-TIME.  The test 
exchange time is now down to 8:05 seconds!  That's 2:39 seconds off the 
orginal exhange time!  Kok, would you also like a bowl of Fish Head Soup?

Can we get a do over on the contest now?  Thanks to all for your help. 
Looking forward to absolutely blazing my way through the next RTTY contest!

73,
Gary AL9A


----- Original Message ----- 
From: "Gary AL9A" <al9a@mtaonline.net>
To: "W6SX Hank Garretson" <w6sx@arrl.net>
Cc: "Writelog Reflector" <writelog@contesting.com>; "RTTY Contesting" 
<rtty@contesting.com>
Sent: March 21, 2011 9:48 AM
Subject: Re: [RTTY] RTTY


> Hi Hank,
>
> Likewise, thanks for the Q's in the contest.  Thanks also for commenting
> that my RTTY seems slow - it seems that way to me too!  Unfortunately, I 
> am
> at a loss to figure out what the true speed is or how to fix it if it is
> slow.  I use WriteLog with the MMTTY plug-in for contest logging.  I've
> checked MMTTY and the baud rate is set to 45.45.  In WriteLog the speed is
> set to 45 baud (60 wpm).  Yet, despite these settings my ear tells me my
> sending speed is slower than many of the stations I am printing.
>
> I will copy this to both the WriteLog and RTTY Contesting reflectors to 
> see
> if  anyone else has an opinion or suggestion.  All comments appreciated.
>
> 73,
> Gary AL9A
>
>
> ----- Original Message ----- 
> From: "W6SX Hank Garretson" <w6sx@arrl.net>
> To: <al9a@arrl.net>
> Sent: March 21, 2011 8:24 AM
> Subject: RTTY
>
>
>>
>> Good Morning Gary,
>>
>> Thanks for all the Qs.
>>
>> I noticed yesterday that your RTTY seems slow. It prints perfectly, but 
>> it
>> seems to my ear to be going out at less than 60 WPM. It just doesn't have
>> the right rhythm. You might want to get someone more expert than me to
>> listen.
>>
>>
>> 73,
>>
>> Hank, W6SX
>>
>> Mammoth Lakes, California
>>
>> Elevation 8083 feet in John Muir's Range of Light
>
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> RTTY@contesting.com
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