[Elecraft] Question about Data Modes...

[David Cole]

Hello,
I am still trying to get my head wrapped around the K3 for RTTY and--
lets say JT65.  

Here is the K3 setup:
1.  Microphone to Mic input, radio set to look for Mic in SSB on MIC
INPUT.
2.  Computer to LINE IN, DATA MODE A set to look to LINE IN for sounds
from the sound-card.
3.  PTT being asserted via RS-232 for data modes, and using a foot
switch for SSB.

Old Pro 3 setup:
When I had my Pro 3, I used the mic input for SSB, and data, using a
Rigblaster to mix inputs when needed.  I avoided the data inputs because
they also offset tuning on the Pro 3, and I was not running FSK, so I
always just used USB for all sound card modes, and did not have to
switch , or rewire anything to change any modes.

I would like that or as close to that as I can get on the K3

New K3 Setup:
Now under the K3, and no Rigblaster, I have JT65 (WSJTx), running
perfectly...  Rig control, decodes, makes contacts, etc...  I am using
DATA MODE A, and LINE IN for audio.  Works like a champ!

However when I go to RTTY using MixW software on the same computer,
leaving the K3 in DATA MODE A, I get the oddest behavior...  I can not
decode RTTY no matter how I try and/or how I tune it.  I have the
waterfall on the computer software showing that I am tuned correctly,
levels are good, but it fails to decide RTTY.  If I force a sideband
switch on the radio and re-tune it still does not decode RTTY, if I
force a sideband switch in the software and re-tune it still fails to
decode RTTY.  In tuning, to center a signal in the passband, the markers
for the signal in the computer waterfall the opposite direction from
what I would expect.  I have the same function running under CW, using
the same tuning method and the radio tunes as expected.  

There is something special about DATA MODE A I am missing.  

HOWEVER...  

If I switch the radio to USB, all decodes fine.  However I can not
transmit RTTY because I am in USB mode, and as such the radio is
expecting the computer RTTY tones to appear in the Mic input, where I
have my microphone, I have the computer wired to the LINE IN.

I really want to be able to run RTTY in DATA MODE A because I don't want
to change mic inputs every time I switch modes between JT65 and RTTY.
Is my assumption that AFSK A can not look at LINE IN correct?

So here are the questions:

1.  If you are running RTTY and any JT65 are you always in DATA A mode,
or do you change between data modes if you switch from JT65 top RTTY?
     a.  If you change to RTTY which mode for the radio, if JT65, which
mode for the radio?
    
2.  Any idea why I can not decode RTTY in DATA A mode?
    a.  I believe it is something to do with my not getting the sideband
settings right in MixW, or on the K3.

3.  What exactly is the difference between DATA MODE A, AFSK A mode, and
SSB?

4.  Are all sound card modes supposed to use the same DATA Mode, either
DATA A or AFSK A?
     a.  If so, why?
     b.  If not, why?

I have Cady's book, but for some reason, (I suspect frustration, and a
preconceived idea of how I think it should work), I am unable to unwind
this problem.  

I see the Cady's book says to use AFSK A for RTTY, and it says use DATA
MODE A for PSK, and I assume JT65, etc.  Why?  This relates to question
3 above...  Can I assign LINE IN as the sound input for both DATA MODE
A, and AFSK A?  

I believe I may be constraining the problem too much to solve it here...
So in short here is my goal:

I want to be able to just switch to DATA on the K3 and have it work for
all sound card modes, with no rewiring, or changing of the
configurations.  Is this possible?

Sorry for the long post, but I am trying to be as clear as possible in
this.

-- 
Thanks and 73's,
For equipment, and software setups and reviews see:
www.nk7z.net
for MixW support see;
http://groups.yahoo.com/neo/groups/mixw/info
for Dopplergram information see:
http://groups.yahoo.com/neo/groups/dopplergram/info
for MM-SSTV see:
http://groups.yahoo.com/neo/groups/MM-SSTV/info