[Elecraft] Impossible mission? USB with the 13khz filter for PSK31on Digipan

[Joe Subich, W4TV]

> I wonder why they setup the radio that way....thats
> a limiting factor when using programs like CW skimmer
> which like Digipan decodes a 3Khz+ swath of CW stations
> all at once......

It looks like DigiPan will run/display up to 5500 Hz - 
that doesn't seem to be a significant benefit above 
the K3's 4200 Hz limit.  

CW Skimmer requires separate I/Q sources in order to do 
broadband decoding and that's not available from the 
K3 audio interface (Line Out).  

I don't know the DAC clock rate is but if possible 
it would be nice to be able to sretch the response to 
5500 or 6000 Hz for occasional use with AM/SWL/etc. 
However, I'd rather see per mode EQ and some extensions 
to the CAT interface first. 

73, 

   ... Joe, W4TV 
 



> -----Original Message-----
> From: Thomas Tumino [mailto:thomastumino at yahoo.com] 
> Sent: Thursday, January 29, 2009 4:35 PM
> To: elecraft at mailman.qth.net; lists at subich.com
> Subject: RE: [Elecraft] Impossible mission? USB with the 
> 13khz filter for PSK31on Digipan
> 
> 
> > Unfortunately, despite specifically enabling the KFL3B-FM
> > 13Khz filter in USB mode, I cannot get 13Khz of bandwidth in 
> > USB receive.  As a matter of fact, I cannot seem to get much 
> > more then 4Khz of receive in USB receive mode. 
> 
> You will not see more than 4 KHz of audio in any mode.  The 
> DSP includes a "brickwall" cut-off at 4200 Hz in SSB, DATA, 
> AM and FM with a lower (2800 Hz) cutoff in CW. 
> 
> 73, 
> 
>    ... Joe, W4TV 
> 
> Joe,
> I wonder why they setup the radio that way....thats
> a limiting factor when using programs like CW skimmer
> which like Digipan decodes a 3Khz+ swath of CW stations
> all at once......
> 73-Tom-N2YTF   
>  
> 
> 
> 
> > -----Original Message-----
> > From: elecraft-bounces at mailman.qth.net
> > [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Thomas Tumino
> > Sent: Thursday, January 29, 2009 12:59 PM
> > To: elecraft at mailman.qth.net
> > Subject: [Elecraft] Impossible mission? USB with the 13khz 
> > filter for PSK31on Digipan
> > 
> > 
> > Hi there,
> > 
> > I am running my K3 with Digipan computer software on PSK 31.
> > I also have a full complement of 5 filters in the K3, with 
> > the widest being the KFL3B-FM 13Khz filter.
> > 
> > Because Digipan can receive many PSK signals at once
> > (Multichannel Window), I would like to set my K3 to receive 
> > USB through the 13Khz filter.  
> > 
> > Unfortunately, despite specifically enabling the KFL3B-FM
> > 13Khz filter in USB mode, I cannot get 13Khz of bandwidth in 
> > USB receive.  As a matter of fact, I cannot seem to get much 
> > more then 4Khz of receive in USB receive mode.  I can get the 
> > XFIL display to tell me I am receiving through the 13Khz 
> > filter, but only about 4Khz of audio will pass through 
> > (perhaps the DSP??).
> > 
> > Am I missing something here, or is this just an oversight in
> > firmware design?  Multichannel simultaneous receive of a 
> > massive chunk of bandwidth is a great feature of Digipan that 
> > I would love to take advantage of with my K3.  
> > 
> > Does someone know how to receive USB at a 13Khz bandwidth 
> with the K3?
> > 
> > 73,
> > Tom-N2YTF
> > 
>