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

[Joe Subich, W4TV]

> 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 
   
 



> -----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
>