[Elecraft] RTTY using DATA mode on K3

[Mike Harris]

G'day,

My AFSK A pitch is set to 1445Hz.  MMTTY (in Logger32) is set to 
default to 1445Hz.

When I start up MMTTY the frequency markers on the waterfall are 
appropriate for 1445Hz paired tones.  If I activate the DUAL PB 
filter the filter is also matched to the tone pair.

If I change the K3 pitch setting then the DUAL PB filter changes to 
the new pitch frequency pair.

Without DUAL PB activated I can receive and transmit anywhere within 
the displayed waterfall, dependent upon the IF bandwidth selected 
simply by clicking on the desired signal.

With DUAL PB activated I can only receive at the pitch frequency 
pair and tuning to a new signal requires use of the VFO.  As 
expected.

With NET ON the MMTTY TX tones follow the RX setting, with NET OFF 
the TX tones remain fixed to the MMTTY pitch setting, in may case 
1445Hz and the receive can be anywhere in the waterfall.  This is 
naturally how one can work narrow split or answers callers off 
frequency, or at least I do.

Now, there is a catch if you have CONFIG: AFSK TX - FIL ON.  The K3 
wraps a 400Hz DSP TX filter around the selected TX pitch pair.  If 
you then try and TX anywhere outside that 400Hz filter there is no 
output.  Like the DUAL PB this filter is shifted to match the K3 
pitch setting.  The default setting is OFF.

In AFSK A mode the K3 displays the RTTY Mark frequency which means 
when I click on a spot the radio is tuned to the spot.  This will 
not happen if you use DATA A, you have to offset the VFO manually to 
go looking for the signal in the waterfall.

For what it's worth.  Oh yes, it's all in the handbook!

Regards,

Mike VP8NO


----- Original Message ----- 
From: "Gary Hinson" <Gary at isect.com>
To: <elecraft at mailman.qth.net>
Sent: Sunday, April 18, 2010 5:13 PM
Subject: Re: [Elecraft] RTTY using DATA mode on K3


Something that caught me out once or twice is that the PC's audio 
output should be close to the K3's
tone settings on RTTy (can't remember if this is DATA or AFSK 
modes - possibly both).  With MMTTY,
it's possible to net the TX tones to the RX tones anywhere on the 
watefall, but if the TX tones are
way off the rig's expected tone frequencies, they are filtered away. 
[This is even without any TX
equalization.]

73
Gary  ZL2iFB


> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Bill
> VanAlstyne W5WVO
> Sent: Monday, 19 April 2010 6:28 AM
> To: Derek Cohn/WB0TUA; elecraft at mailman.qth.net
> Subject: Re: [Elecraft] RTTY using DATA mode on K3
>
> Hi Derek,
>
> When using a computer and sound card to drive the K3 in any
> digital mode,
> your data mode should be set to DATA A. Somebody will correct
> me if I'm
> wrong, but I suspect that's your problem.
>
> DATA A mode is basically equivalent to the USB/LSB position,
> except that
> equalization and compression are disabled.
>
> Bill W5VWO
>
>
> --------------------------------------------------
> From: "Derek Cohn/WB0TUA" <vibroplex at mindspring.com>
> Sent: Sunday, April 18, 2010 9:53 AM
> To: <elecraft at mailman.qth.net>
> Subject: [Elecraft] RTTY using DATA mode on K3
>
> > Hi Everyone,
> >
> > I just bought a K3 a few weeks ago and have been using it
> on CW.  It's
> > time to play with it a bit on RTTY.  I'm using the
> Tigetronics Signalink
> > to interface the radio to my PC which is running MMTTY.
> When I have the
> > mode switch in the sideband position, copy on the laptop is
> just fine and
> > the signals display properly on the tuning aids in MMTTY.
> I read the
> > manual pages about better performance if the DATA mode is
> selected.  I
> > switched to the DATA mode and there is very little audio in
> the speaker
> > and no signals displayed on the tuning aids in MMTTY.  No
> copy either.  I
> > double-checked the data mode setting and it is AFSK-A which
> I think is
> > correct.  I must have a setting wrong somewhere.  I've gone
> over the data
> > section in the manual a few more times but don't see what
> I'm doing wrong.
> > Any ideas?
> >
> > Thanks and 73,
> >
> > Derek Cohn
> > Morse Telegraph Club - Alton Chapter
> > Office UD, Sine DJ
> > Amateur Radio Station - WBØTUA