[Elecraft] K3: "Mixing" sub-RX audio in stereo headphones

[David Gilbert]

Yes, shifting the signal lower is important for good intelligibility 
when using the narrower filters.  I bought the 8-pole 1.5 KHz filter for 
the K3 directly from Inrad and I love it, but I find it works best if I 
shift the center frequency all the way down to  around 1.0 KHz +/-  0.05 
KHz.   In case anyone isn't aware of that particular filter, you can 
check it out at 
http://www.inrad.net/product.php?productid=299&cat=140&page=1

As far as I know, Elecraft has still not added menu options for setting 
which audio channels go to which ear when using the subreceiver, and 
right now the default is main-in-left and sub-in-right.  Back in April, 
though, Lyle provided some K3 commands that will direct the audio in 
other ways, and the command to put both channels in both ears is:

!bedb;

Lyle added this caution at the time:

"Be sure SPKRS+PH is OFF, or SPKRS=2, with these commands."


You can program the K3 Utility application to send commands to the K3, 
but I think it makes more sense to use your contest logger to do it in 
this case since this workaround command isn't permanent ... the K3 
reverts to the default condition every time you disengage the 
subreceiver or turn off the K3 (other actions may have the same 
effect).  The K3 can only be controlled by one application at a time, so 
if you rely on the K3 Utility to send the command you have to exit the 
logger each time you need reset the audio the way you want it.

I use N1MM for contesting and I've programmed one of the function keys 
to send !bed7; to the K3, which is the command for main-in-both and 
sub-in-right.  That way it only takes one keystroke or one mouse click 
to restore the audio routing to the way I want it.  The N1MM command 
string to do that is:

{CATA1ASC <21>bed7;}  {CATA2ASC <21>bed7;}

which handles both VFOs no matter which one you are using.  The <21> is 
the hex representation for ! and is necessary since N1MM reserves the 
ASCII version of that character for a different macro.  A totally 
equivalent command string in hex form is:

{CATA1HEX 21626564373b}  {CATA2HEX 21626564373b}   for !bed7;

In K1LI's case, to put both main and sub in both ears from within N1MM 
he would use:

{CATA1ASC <21>bedb;}  {CATA2ASC <21>bedb;}

or equivalently

{CATA1HEX 21626564623b}  {CATA2HEX 21626564623b}


Other potentially useful K3 commands are:

!bef9;        main-in-left, sub-in-both

!bed1;        main-in-left, sub-in-right   (default condition)


I'm hoping that the capability to set the audio mix via a menu option 
hasn't disappeared from the Elecraft to-do list, but in the meantime the 
workaround commands mostly get the job done.

Hope this helps.  73,
Dave   AB7E




dalspaugh at comcast.net wrote:
> Have you tried just shifting the signal to a lower freq. (rotating the shift knob counter clockwise). That seems to make it sound very good to me. 
>
>
> 73 Doug N3QW 
>
>
>
> ----- Original Message ----- 
> From: "Brian Machesney" <nekvtster at gmail.com> 
> To: "Elecraft Reflector" <elecraft at mailman.qth.net> 
> Sent: Tuesday, October 20, 2009 4:14:16 PM GMT -05:00 US/Canada Eastern 
> Subject: [Elecraft] K3: "Mixing" sub-RX audio in stereo headphones 
>
> I have the 8-pole 1.8-kHz filter for phone contesting, but it's on the 
> border of intelligibility for my ears. I want to overcome this by mixing in 
> a small amount of wider-bandwidth audio from the linked sub-RX with a wider 
> filter. While I can set SPKRS to 1 to accomplish this, it seems that with 
> stereo *headphones* I am forced to have the main and sub in left and right 
> ears rather than mixed together into both ears. 
>
> Any hints on how I can do this? Have I missed something in the manual? Do I 
> have to plug my stereo headphones into the speaker jack? 
>
>