[WriteLog] BARTG 75 setup

Thu Apr 25 20:44:12 EDT 2013

Ok Joe, you've hit the nail on the head again!  When I change profiles in my 
clone RttyRite window to something other than the AA6YQ profile it decodes 
just fine at 75 baud.  I guess I need to read the MMTTY docs though about 
how to make a copy of the AA6YQ profile and then tweak some of the settings 
as you suggest.  I see there is a section in the USERPARA.INI file called

[Define4]
Name=AA6YQ FIR512

I suppose I could just copy this section somewhere else and save it then do 
the modifications via the MMTTY screens.  If they work, or not, I could just 
copy this section back into the USERPARA.INI file and restore it to original 
condition.  Or, just make a backup copy of the entire USERPARA.INI file with 
a different name and then restore that.  I'll give this a try later tonight. 
Thanks again.

73,
Gary AL9A

----- Original Message ----- 
From: "Joe Subich, W4TV" <lists at subich.com>
To: <writelog at contesting.com>
Sent: April 24, 2013 10:35 PM
Subject: Re: [WriteLog] BARTG 75 setup

>
>> In the second clone window running XMMT.ocx and MMTTY with the AA6YQ
>> profile I have set the Mode to 75 baud in RttyRite and in its MMTTY
>> instance. However, the decoding in this clone window is still not
>> perfect.
>
> Don't even think abut using the AA6YQ profile for 75 baud.  The filters
> are simply too narrow for the added bandwidth.  You are seeing the
> effects of inter-symbol interference from channel (Mark/Space) filters
> that are close to optimum for 45.45 baud but have far too much delay
> for 75 baud.
>
> The AA6YQ profile has *two* cascaded 512 tap filters in each decoder
> channel - the "Dual Peak filter" as a bandpass filter and a second
> 512 tap FIR resonator for each channel.  Each of those resonators is
> 35 Hz wide - far too narrow for 75 baud.
>
> I'd copy the AA6YQ profile ... *uncheck* the Dual Peak filter on the
> Demodulator tab, change the TAP in the Discriminator box to 386 and
> increase the FW setting in the Pre-Filter/BPF to 150 as a starting
> point for 75 baud work.   In addition, I would enable ATC (AFC/ATC
> tab) and set sweep to .3
>
> 73,
>
>    ... Joe, W4TV
>
>
> On 4/25/2013 12:41 AM, Gary AL9A wrote:
>> Thanks for the help Joe.  I followed the new WriteLog and MK II setup
>> instructions at the support page and I can now send 75 baud using
>> XMMT.ocx using MMTTY per the instructions.  I'm not sure what changed in
>> the setup I was already using, but obviously something got reset.
>>
>> So now my situation is this.  I can send at 75 baud in the main RttyRite
>> window and what I'm sending decodes correctly in the blue italic font.
>> In the clone 2Tone window Setup is set to 75 baud and the RttyRite
>> window has the Mode set to 75 baud.  When I send a macro at 75 baud
>> 2Tone decodes it properly in that clone window.  In the second clone
>> window running XMMT.ocx and MMTTY with the AA6YQ profile I have set the
>> Mode to 75 baud in RttyRite and in its MMTTY instance.  However, the
>> decoding in this clone window is still not perfect.  I can see some of
>> my macro message decoding, but many of the characters are still
>> garbled.  I'm not sure what will happen with this window under "live"
>> receive at 75 baud when on the air signals are coming in.
>>
>> I will continue to try various things with the second RttyRite clone
>> window and see if I can get it to decode better.  Perhaps a different
>> profile other than the AA6YQ one?
>>
>> 73,
>> Gary AL9A
>>
>>
>>
>>
>> ----- Original Message ----- From: "Joe Subich, W4TV" <lists at subich.com>
>> To: <writelog at contesting.com>; "Gary AL9A" <al9a at mtaonline.net>; "DONALD
>> A HILL" <aa5au at bellsouth.net>
>> Sent: April 24, 2013 6:41 PM
>> Subject: Re: [WriteLog] BARTG 75 setup
>>
>>
>>>
>>>
>>>
>>> On 4/24/2013 9:53 PM, Gary AL9A wrote:
>>>>
>>>> So unless I am missing something here, when using the XMMT.ocx 
>>>> interface
>>>> it will not be possible to achieve 75 baud unless you use Hardware
>>>> generated FSK.  But Hardware generated FSK with XMMT.ocx will produce
>>>> the buffer timing speed issue that is unacceptable.  So now my thinking
>>>> is that in order to run 75 baud for the BARTG 75 I must go back and
>>>> reinstall the MMTTY plug-in and use that for the RttyRite transmit
>>>> window at 75 baud  instead of XMMT.ocx?  As I am typing this my mind is
>>>> now asking should I delete all my RttyRite sections in the ini file an
>>>> let WL rebuild those too?  Life ain't simple out here on the bleeding
>>>> edge!
>>>
>>> Gary,
>>>
>>> Go to the MK II area at www.microHAM-USA.com/Support.html, download the
>>> updated configuration for Writelog and MK II *and follow it* for the
>>> SM6SRW MMTTY Plug-in for Writelog or the XMMT.ocx interface using FSK.
>>>
>>> I have just checked and *both* work perfectly at 75 baud.  I was able
>>> to transmit at 75 baud and receive on a different system at 75 baud in
>>> either 2Tone or MMTTY (using WinWarbler) as well as the decoder built
>>> into the K3.
>>>
>>> You *must* use MMTTY to generate the FSK - *DO NOT* attempt to use the
>>> WriteLog software (or hardware) generated FSK.  It appears that one can
>>> not select 75 baud with *hardware* generated FSK and the SM6SRW MMTTY
>>> Plug-in for WriteLog (although it is possible to use Hardware generated
>>> FSK at 75 baud with XMMT.ocx).
>>>
>>> It will be necessary to set the baud rate in MMTTY (Options | Setup
>>> MMTTY | Decode tab) ... I recommend defining a "Profile" for 75 baud
>>> so you can return to it quickly.  Also make sure "Fixes 45.45" is *NOT*
>>> checked in HAM Default or every time you chick "HAM" the data rate will
>>> be reset to 45.45 baud.
>>>
>>> Software Generated FSK is 45.45 baud only and can not be used for this
>>> contest.
>>>
>>>
>>> 73,
>>>
>>>    ... Joe, W4TV
>>>
>>
>> _______________________________________________
>> WriteLog mailing list
>> WriteLog at contesting.com
>> http://lists.contesting.com/mailman/listinfo/writelog
>> WriteLog on the web:  http://www.writelog.com/
>>
> _______________________________________________
> WriteLog mailing list
> WriteLog at contesting.com
> http://lists.contesting.com/mailman/listinfo/writelog
> WriteLog on the web:  http://www.writelog.com/
> 