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Re: [WriteLog] MMTTY/2Tone (now Hardware generated FSK withmicroKEYER)

To: <writelog@contesting.com>
Subject: Re: [WriteLog] MMTTY/2Tone (now Hardware generated FSK withmicroKEYER)
From: "Gary AL9A" <al9a@mtaonline.net>
Date: Mon, 1 Apr 2013 07:58:11 -0800
List-post: <writelog@contesting.com">mailto:writelog@contesting.com>
Thanks to both Ed and Joe for the clairifactions on Strict BPS and MMTTY. I sort of thought it was something in either router or MMTTY, but just didn't know where to look. We've got two sick grandkids who are staying home from school today so I'm not sure when I will be able to sit down and play around a bit with various settings. I'll be sure to let the group know how it works out.

73,
Gary AL9A


----- Original Message ----- From: "Joe Subich, W4TV" <lists@subich.com>
To: <writelog@contesting.com>
Sent: April 01, 2013 5:04 AM
Subject: Re: [WriteLog] MMTTY/2Tone (now Hardware generated FSK withmicroKEYER)



The short answer is that you must go into the microHAM Router and
check "Strict BPS" when you use Rttyrite's Hardware generated FSK.
This may slow the data rate a bit, though Joe mentioned it was not
as bad as he previously thought.

Ed is correct ...

When "C: Limiting Speed" is selected in MMTTY's "USB Port" dialog, MMTTY paces its FSK output - that is it sends one character to the
serial port every 165 ms.  This allows MMTTY to know what has been
sent (more importantly if there is still data to be sent) so it knows
when to drop PTT.  This is necessary because the system level drivers
for USB hardware have very large buffers that can not be disabled.
Software that does not use some form of pacing gets confused and either
sends too many diddles or drop PTT early (or both).

The equivalent to "limiting speed" in the Eltima VSPAX used in microHAM
Router is "strict BPS" which only sends a single character at a time to
Router.  Unfortunately, because the VSPAX is dealing with 8 bit data
instead of 5 bit (7.5 bit with start/stop bits) data, it calculates the
character rate at 176 (22 x 8) ms instead of 165 msec which results in
a slightly "slow" data (equivalent to 5N2 instead of 5N1.5).

When using "Hardware generated FSK" in WriteLog one must use "strict
BPS" in Router.  With MMTTY the alternative is to set no FSK port in
RTTYrite and configure MMTTY to generate the FSK.

Now that I have returned from my trip to Ohio for my mother's 90th
birthday, I will update the WriteLog examples for all of the microHAM
"Keyer" interfaces to document the new MMTTY interface and the option
of "Hardware generated FSK" with "Strict BPS" or MMTTY with "C:
Limiting Speed".  I had not expected a release while I was gone!

73,

   ... Joe, W4TV


On 4/1/2013 7:03 AM, Ed Muns wrote:
This is similar to Jim N7US's experience he posted yesterday and its taken me this long to register what the issue might be. I saw the same symptoms on a friend's system that used the original microKEYER, but the problem may
be the same.

The short answer is that you must go into the microHAM Router and check
"Strict BPS" when you use Rttyrite's Hardware generated FSK. This may slow the data rate a bit, though Joe mentioned it was not as bad as he previously
thought.

The long answer ...

I forget why this isn't a problem with the MMTTY Plug-in.  Perhaps the
Plug-in gets the COM port number from Rttyrite's Port menu but still uses
MMTTY's FSK facility.  But, then I can't explain why this avoids the USB
buffering problem in the Router that Strict BPS gets around. Perhaps some
detail that differs between Rttyrite's hardware FSK and MMTTY's. Joe will
know.

An alternative, if you use MMTTY as your main decoder/encoder, is to select "None" in the Rttyrite Port menu and use the MMTTY FSK feature, setting the
COM port number on the TX tab of the MMTTY Options window.

If using 2Tone for the main decoder, you must use Rttyrite's FSK facility
since there is not true FSK capability. If you use Hardware generated FSK, set "Strict BPS" in the Router. If you use Software generated FSK, it only
works with 45.45 Baud (60 wpm) RTTY.

And, finally, there is the option of using 2Tone's "Pseudo FSK" mode but
this requires a special hardware interface.  It is described in the 2Tone
PDF:

"TX FSK: The Pseudo FSK setting outputs a 5KHz tone on both left and right
channels of the selected
sound card. Tone is on for space and off for mark. A suitable detector
circuit can be found at
http://www.w1hkj.com/FldigiHelp-3.20/PseudoFSK.html but use 0.1uF in place
of 0.5uF. The output
connects to the FSK input of the rig. Search & Pounce: as the transmit
frequency does not change
with AFC, tune the rig so the small vertical AFC lines are co-incident with
or very close to the long
vertical lines. Not doing this will result in off frequency transmission."

When Joe resurfaces, he may have further comment.  Let me know if this
helps.

Ed W0YK

Gary AL9A wrote:
I seem to have hit a bit of a stumbling block...

Downloaded WL V11.10G and installed the new update.  I
already had XMMT.ocx registered on my Vista machine because
of an earlier install of N1MM a couple of years ago. Cleared
out my RttyRite section in the ini file and then followed
Don's directions on his web page.  I can get both MMTTY and
2Tone to run using the ocx option on the TU Type menu, but
there is something not right in both instances.  When sending
a macro the text appears to jump instantly onto the RttyRite
screen, but the transmission is a problem.  Either the TX
drops out right away after just a few characters are sent or
it sends a part of the string then hangs up for a couple of
seconds and sends more of the macro then hangs up again.
Sometimes it takes several seconds to TX to turn off despite
having %E at the end of the macro.  This happens with both
2Tone and MMTTY under ocx control.  It sounds like those K3
ops who are using a CW paddle to key their RTTY transmissions.

When I switch back to the MMTTY plug in choice in the TU Type
menu it transmits normally again.  The only thing I notice
that is different is that with the ocx option selected in the
Ports drop down list there are three FSK keying options.  The
last one in the list is checked - Hardware FSK.  I have the
microHAM Router software running and use the MK II for FSK.
Is there a setting somewhere I'm missing in RttyRite, MMTTY,
2Tone or Router?  Not sure where to go or what to try next.

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