[Elecraft] K-3: USB SignaLink for better RTTY decoding?

[Wes Stewart]

I have used a Signalink with my K3 with good results. I have cables (and headers) for both the K3 and my Kenwood TS-870 and have used it with both radios.  However, when I added a SDR-IQ as a panadapter to the K3 I ran out of USB ports on my laptop and went to a straight connection from the K3 Line In/Out to the built-in sound card on the Lenovo T400 laptop. (I use a second monitor for more screen real estate) Performance has been acceptable but I have not done an A/B comparison with two instances of MMTTY running. The Signalink might be better (or worse) but I can't say.

In the K3 I have the 400 Hz, 8-pole filter and usually use a 200 Hz DSP BW without the dual peak turned on.

The Signalink is AFSK only and to use the better FSK filtering in my Kenwood, I have built a prototype FSK decoder board that decodes the Signalink AFSK signal to a digital signal for direct FSK transmit.  I was well on the way to committing this to a PC board that would install inside the Signalink case, but my lovely wife passed away early last month and I've lost all interest in this project (and a lot of other things).

In testing the FSK board I've used the K3 as the receiver and can say that the K3 internal RTTY decoder is very poor compared to MMTTY using the laptop soundcard.

Wes  N7WS

--- On Wed, 2/23/11, RLVZ at aol.com <RLVZ at aol.com> wrote:
>  
> Hi Guys,
>  
> I really like the K-3 for RTTY.  But I'm trying to
> maximize  reception as 
> during contests I often hear stations calling me that I
> can't  copy.  I 
> believe the weakest link with my RTTY reception is
> the  SoundCard in my current 
> Desktop.  I say this because I use a  different
> Desktop while operating from 
> my Midwest QTH and  that computer seems to decode weak
> signals with the same 
> K-3 a lot  better.  Funny thing is that the
> processor in that Desktop that  
> decodes better is about 50% slower.  So my question
> is: do  you thinking 
> replacing my current Desktop's SoundCard with a USB 
> SignaLink would improve 
> weak signal RTTY reception?  Note: I have done 
> various routines to calibrate 
> the Desktop Sound Card with little  improvement.
>  
> Thanks & 73,
>  
> Dick- K9OM