Using EXTFSK(64) or for that matter 2Tone FSK using bit diddling of a COM
port control line is one way of making sure you get extra errors on the far
ends decode and being asked to repeat.
Windows is not a real time operating system and so there is substantial
timing jitter. The transmitted signal will have some bits that are longer
than they should be and others that are shorter than they should be. This
will lead to decode errors at the receiver.
This can be avoided by using AFSK (if you use MMTTY AFSK then make sure the
TX bandpass filtering is on and tap is set to 512). 2Tone has its filtering
on all the time. This will also ensure your signal is much narrower than
most radios FSK signal. You fellow RTTY enthusiasts will appreciate your
narrow TX bandwidth and they will get better copy of you too.
Having invested in all that expensive kit, you really should radiate a
signal that is narrow and has the lowest decode error rate.
73 David G3YYD
-----Original Message-----
From: RTTY [mailto:rtty-bounces@contesting.com] On Behalf Of Joe Subich,
W4TV
Sent: 26 October 2017 02:59
To: rtty@contesting.com
Subject: Re: [RTTY] Intel NUC, anyone?
> I googled around and came to Don AA5AU's page and was reminded of
> EXTFSK ... I gather this will let me use just about any USB-serial
> adapter for RTTY? Does it also support 75-baud?
No.
> Seems like it was limited to only 45.45 at one point but was it maybe
> updated recently?
ETFSK64 (EXTFSK2) http://www.qsl.net/ja7ude/extfsk/indexe.html *IF* you have
a processor with at least four execution units (eight "CPUs" in Resource
Monitor or eight "Processors" in Windows Device Manager).
73,
... Joe, W4TV
On 10/25/2017 10:31 PM, Peter Laws wrote:
> So I ended up getting a tall i3 and a 16-GB SODIMM (leaving me a slot
> for another one just like it down the road). The 40-GB 2.5" SSD I
> had turned out to be ... not really big enough for W10. Yes, I got
> rid of hiberfil.sys and removed a bunch of other stuff and had about
> 18 GB free when I was done but I could see this would be a pain point
> in the future so picked up a 120 GB SanDisk at the local Blue Polo and
> Khaki place. I thought about a "certified refurb" but the fact that
> the NUCs will run on 12 V dc realllllly got my attention. I'll need
> to get a 12 V dc-capable display at some point, but that's later.
>
> Now my problem is that the NUC has no serial ports. I *knew* this but
> hadn't *thought* about it if you know what I mean. I have a Siig
> 4-port serial to USB adapter (no idea which chipset) and, I think a
> single port Keyspan (no idea there either) somewhere but then there's
> the UART-not-liking-45.45-baud thing. I googled around and came to
> Don AA5AU's page and was reminded of EXTFSK ... I gather this will let
> me use just about any USB-serial adapter for RTTY? Does it also
> support 75-baud? Seems like it was limited to only 45.45 at one point
> but was it maybe updated recently?
>
> Enquiring minds want to know! And I know Chen's opinion of hard-keyed
> FSK ... :-D The serial line will then go to the RigBlaster+ and then
> to the IC-746Pro.
>
> Peter
>
> On Sun, Oct 1, 2017 at 12:29 PM, Jeff Stai <wk6i.jeff@gmail.com> wrote:
>> Another option is to purchase one of the many PCs coming off lease
>> and are refurbished. You can find these on Amazon, Newegg, and so on.
>> With these units you have the opportunity to stay at Win7 if you
>> wish, they often have a native serial port, support for two monitors,
>> and have some flavor of PCI card slot under the hood. Prices can be
>> under $200, even. Have fun! - jeff wk6i
>>
>> On Sat, Sep 30, 2017 at 1:40 PM, Peter Laws <plaws0@gmail.com> wrote:
>>>
>>> I've been dancing around replacing the PC at N5UWY (2006 Dell
>>> Precision
>>> 670
>>> with a Xeon or two - I forget - and 16 GB RAM) for quite some time
>>> now but have now been introduced to Intel's little NUC boxes. If
>>> you don't mind a Celery processor, they're really cheap. As soon as
>>> you make the jump to a Core i3 (or i5 or i7), the price jumps up a
>>> lot but still +/-$300 if you don't go nuts.
>>>
>>> Some cases have room for a 2.5" disk, some don't. No room inside
>>> for "cards" but no one cares. Some do have MB headers for serial
>>> ports if you are desperate. Plenty of USB 2 and 3 and
>>> DP/Thunderbolt and HDMI and SATA connectors depending on which
>>> version you get. These things also run on
>>> "12-19 V dc", which opens up interesting possibilities.
>>>
>>> So my question is this ... how much of the processing for RTTY is
>>> done by the sound device (avoiding $0.99 USB dongles) and how much
>>> is done by the CPU? Will their least expensive Core i3 be adequate?
>>> I'm assuming the answer is yes but really need more expert advice.
>>> What about for more DSP-intensive stuff like the JT modes?
>>>
>>>
>>> Here's an example:
>>> https://www.newegg.com/Product/Product.aspx?Item=56-102-168
>>>
>>>
>>> --
>>> Peter Laws | N5UWY | plaws plaws net | Travel by Train!
>>> _______________________________________________
>>> RTTY mailing list
>>> RTTY@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rtty
>>
>>
>>
>>
>> --
>> Jeff Stai ~ wk6i.jeff@gmail.com
>> Twisted Oak Winery ~ http://www.twistedoak.com/ Facebook ~
>> http://www.facebook.com/twistedoak
>
>
>
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