[RTTY] EXTFSK64 Re: [MMTTY] 75 baud RTTY with EXTFSK ...

Mon Sep 22 00:27:26 EDT 2014

Yes it did Hisami-san!  Thank you for both of my JA QSOs at 75 baud.

73,
Gary AL9A

-----Original Message----- 
From: 7L4IOU
Sent: September 21, 2014 7:07 PM
To: RTTY
Subject: [RTTY] EXTFSK64 Re: [MMTTY] 75 baud RTTY with EXTFSK ...

Hello Friends,

This post is raked up 3 years old thread. hi

There were two problems in conventional EXTFSK.
One, can not keying 75 baudot FSK.
Two, does not work for LPT port of 64 bit Windows.

I found New EXTFSK64 in the JA7UDE's Web page.

<http://www.qsl.net/ja7ude/extfsk/>

and it's a beta version,
but worked very well with N1MM+ this morning.

Oba-san, Thank you very much!

73, Hisami 7L4IOU

>--- Original Message ---
>From:     Robert Chudek - K0RC <k0rc at citlink.net>
>To:       "Joe Subich, W4TV" <lists at subich.com>
>Subject:  Re: [RTTY] [MMTTY] 75 baud RTTY with EXTFSK ...
>Date:     Wed, 21 Sep 2011 00:29:53 -0500

>/"Have you tried running FSK on the *serial* port?"/
>
>Well there you go! I couldn't see the forest for all the trees in the
>way! I had COM1 = CAT stuck in my brain and had not given it any other
>consideration! But wait... there's even more... I think I'm on a roll...
>
>my docking station has three slots for PCI cards... that gives me
>another option. I guess I've broken through my brickwall and have
>plenty
>of experiments I can run. Thanks again for the insight.
>
>73 de Bob - KØRC in MN
>----------------------------------------------------------------------
>--
>
>On 9/20/2011 11:12 PM, Joe Subich, W4TV wrote:
>>
>> Bob,
>>
>>> And of course, as you pointed out, there are a variety of other
>>> methods to operate at 75 baud. My contesting computer is an older
>>> Dell laptop C640 with a docking station. It provides one serial and
>>> one parallel port. The serial port runs the CAT and FSK / PTT run
>>> from the LPT port.
>>
>> Have you tried running FSK on the *serial* port?  If it is a real
>> serial port (and it may be if you have a true docking station
>> instead
>> of a multifunction USB adapter), it should run both 45.45 and 75
>> baud with MMTTY or MMVARI using the standard drivers (serial port
>> for MMTTY and FSK8250 for MMVARI).   It would be very easy to add
>> a generic USB converter for CAT/CW/PTT.
>>
>>> These manufacturers discuss thr top speed but there is no mention
>>> of
>>> the lowest speed supported. The second link refers to the MCS9835
>>> LSI
>>> device which supports 5, 6, 7, and 8 bits, which sounds promising.
>>
>> The MCS9835 is a MOSCHIP device that is capable of providing two
>> 16C550 compatible serial ports and one parallel port depending on
>> the external components.  A 16C550 compatible serial port should be
>> capable of 45.45 baud operation and while the data sheet:
>>      http://www.comet.bg/datasheet/Interface/9835.pdf
>> does not specifically list a baud rate divisor for 45.45 baud, the
>> 1.8432 MHz baud rate clock is low enough and the baud rate table
>> shows a divisor of 1 for 115.2 K that 45.45 would surely be
>> available
>> with a baud rate divisor of 09E6(h) or 09E7(h) (45.46 or 45.44 baud).
>> Assuming the divisor is a 12 bit number as in the 8250/16450 UART
>> and
>> FTDI USB UART, the lowest (standard) data rate would be 30 baud.
>>
>> > What is your opinion of finding a PCMCIA adapter that might be
>> > "slow
>> > enough" to direct key FSK from MMTTY?
>>
>> There are plenty out there ... two port PCMCIA adapters were a
>> common
>> solution for laptops before USB became so ubiquitous.
>>
>> 73,
>>
>>    ... Joe, W4TV
>>
>>
>>
>> On 9/20/2011 10:57 PM, Robert Chudek - K0RC wrote:
>>> Hello Joe,
>>>
>>> Thanks for the detailed technical background regarding the
>>> limitation of
>>> the implementation of the EXTFSK driver. It's no secret I have been
>>> vocal about the possibility of extending the capability to 75 baud.
>>> Unfortunately I don't have the programming background or skill to
>>> meddle
>>> with the source code.
>>>
>>> And of course, as you pointed out, there are a variety of other
>>> methods
>>> to operate at 75 baud. My contesting computer is an older Dell
>>> laptop
>>> C640 with a docking station. It provides one serial and one
>>> parallel
>>> port. The serial port runs the CAT and FSK / PTT run from the LPT
>>> port.
>>> This has worked fine for years. (Yes, I am waiting for Ed McMahon
>>> to
>>> show up with the check, then I'll upgrade!)
>>>
>>> This discussion made a light bulb come on... the laptop has a pair
>>> of
>>> PCMCIA ports. I see a variety of PCMCIA adapters that provide
>>> serial
>>> ports. Here's a couple examples:
>>>
>>> *http://tinyurl.com/6ed3869*
>>>
>>> *http://tinyurl.com/2z2c2w*
>>>
>>> These manufacturers discuss thr top speed but there is no mention
>>> of the
>>> lowest speed supported. The second link refers to the MCS9835 LSI
>>> device
>>> which supports 5, 6, 7, and 8 bits, which sounds promising.
>>>
>>> What is your opinion of finding a PCMCIA adapter that might be
>>> "slow
>>> enough" to direct key FSK from MMTTY?
>>>
>>> 73 de Bob - KØRC in MN
>>> -------------------------------------------------------------------
>>> -----
>>>
>>> On 9/20/2011 8:35 PM, Joe Subich, W4TV wrote:
>>>>
>>>>
>>>>  From time to time I see comments that some individuals would like
>>>> to
>>>> see JE3HHT modify EXTFSK to support 75 baud RTTY. I have recently
>>>> exchanged e-mail with Oba, JA7UDE about that possibility and Oba
>>>> advises that he attempted to add 75 baud support to EXTFSK some
>>>> years
>>>> ago without success due to problems with bit period instability
>>>> (jitter).
>>>>
>>>> EXTFSK uses the Windows Multimedia Timer that has a maximum
>>>> resolution
>>>> of 1 millisecond. However, the timer is not stable due to the
>>>> nature
>>>> of Windows process swapping, etc. I have measurements (scope
>>>> photos)
>>>> made by OM7ZZ at microHAM which show the 22 millisecond bit period
>>>> from EXTFSK will vary +/- 2 ms (+/- 10%) on either a motherboard
>>>> UART
>>>> or USB converter (measurements made on both devices to eliminate
>>>> the
>>>> effects of USB latency). The instability (jitter) is due to the MM
>>>> timer and thread switching in the Windows operating system.
>>>>
>>>> If we apply a 1 millisecond resolution and 2 millisecond jitter to
>>>> 75
>>>> baud, we start out at 77 baud (13 ms bit period). With 2ms jitter,
>>>> the baud rate can vary from as low as 66.6 (15 ms bit duration) to
>>>> as
>>>> high as 91 (11 ms bit duration). A +/-15% instability in baud rate
>>>> will result in significant performance issues.
>>>>
>>>> There are other solutions for 75 baud FSK operation with MMTTY. If
>>>> you
>>>> have a serial port (motherboard or add-in card) MMTTY will support
>>>> it
>>>> directly. If you have only USB ports, some of the better
>>>> interfaces
>>>> (all of the microHAM "Keyers", RigExpert Standard and Plus,
>>>> Navigator
>>>> by US Interface) support 45 and 75 baud operation using a UART
>>>> (serial
>>>> port) compatible interface, or you could use an AFSK to FSK
>>>> converter
>>>> like the FSKit by K4DSP in the August 2011 QST (pp 40-42).
>>>>
>>>> Finally, one can always use AFSK.
>>>>
>>>> By the way, JE3HHT has released the source code of EXTFSK to the
>>>> public
>>>> domain. Anyone is free to add 75 baud support if they wish. There
>>>> are
>>>> additional timers with better resolution in Windows 2000 and later.
>>>> It
>>>> would not be at all inconceivable for a dedicated programmer who
>>>> was
>>>> willing to do the research and work to use the same basic approach
>>>> with
>>>> a different timer to add 75 and 110 baud support to EXTFSK if they
>>>> wanted to do so. The source code is part of EXTFSK106.zip
>>>> available
>>>> from www.hamsoft.ca ... have at it boys!.
>>>>
>>>> 73,
>>>>
>>>> ... Joe, W4TV
>>>>
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