[Elecraft] Setup problems with k3s and rtty

Joe Subich, W4TV lists at subich.com
Sat Aug 15 16:35:16 EDT 2015


 > 2. If COM1 is a USB-to-serial adapter rather than a true serial port,
 > then you will need to use EXTFSK with MMTTY; standard single-port
 > USB-to-serial adapters cannot go slowly enough to do 45.45 baud RTTY.

If you have hardware that forces you to use EXTFSK, locate and download
EXTFSK64 (if you have an i5 or i7 CPU and > 4GB of RAM) or stick with
AFSK.  The original EXTFSK uses the old Windows Multi-media timer and
suffers greatly from bit jitter.  EXTFSK64 reduces jitter by nearly
90%.

Bit-jitter is effectively applying flutter to your transmit signal - it
can make an otherwise "solid" signal marginal and will make a marginal
signal impossible to copy.

73,

    ... Joe, W4TV


On 8/15/2015 4:22 PM, Richard Ferch wrote:
> 1. With the K3/K3S, FSK is *not* better than AFSK. In fact, before
> firmware version 4.66 in March 2013, the K3's tranmitted signal in AFSK
> was demonstrably cleaner than its signal in FSK. Now they are about equal.
>
> 2. If COM1 is a USB-to-serial adapter rather than a true serial port,
> then you will need to use EXTFSK with MMTTY; standard single-port
> USB-to-serial adapters cannot go slowly enough to do 45.45 baud RTTY.
>
> 3. There are either two (N1MM+ and MMTTY) or three (N1MM+, MMTTY and
> EXTFSK) programs involved. Only one of them has direct access to COM1.
> You should not have COM1 configured at all in N1MM Logger+. If COM1 is a
> true serial port, MMTTY should be configured to use COM1 as its PTT &
> FSK port. If COM1 is a USB-to-serial adapter, MMTTY should be configured
> to use EXTFSK as its PTT & FSK port, and EXTFSK should be configured to
> use COM1.
>
> I think it would have been simpler to stick with AFSK.
>
> 73,
> Rich VE3KI
>
>
>
> NR4C wrote:
>
>> I'm trying to set up my Elecraft kilo-3-sugar with FSK for the Roundup
>> tomorrow.  I \
>> have an interface by AC8Y. It's plugged into the serial port com1 on
>> my computer. \
>> Every time I try to tell n1mm to use com1 for CW, PTT, or DIG I'm told
>> that com1 is \
>> in use by another program and is configured by n1mm and n1mm won't
>> work until this is \
>> resolved. Well fancy that!  Of course it's in use. It's the interface
>> I'm trying to \
>> use for n1mm!!!!
>>
>> This seems crazy to me.
>>
>> I wish I could just go back to AFSK and my one cable setup. But now
>> all my AFSK \
>> settings are trashed. If FSK is so much better why don't it work easier?
>


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