[Elecraft] K3 Beta Firmware Release -- MCU Revision 2.22

[Matt Zilmer]

You have to use the 6 KHz filter for TX on ESSB.  You're TX is
probably restricted on audio bandwidth with the 2.7 filter.

From hfnotes.rtf for 2.23: 

* ESSB (EXTENDED SINGLE SIDEBAND) ADDED:  Allows the K3 to transmit in
SSB  modes at a bandwidth of up to about 4 kHz. Requires a 6 kHz
crystal filter on the RF board. 

To use ESSB: 
(1) Make sure the 6 kHz filter is configured correctly  for AM
transmit; switch to AM mode, then specify this filter using
CONFIG:FLTX AM.  
(2) Locate CONFIG:TX ESSB. Select the desired extended bandwidth for
SSB ransmit (3.0 to 4.0 kHz) using VFO A. Then tap"1"  on the keypad
to turn ESSB on/off. When on, the "+" icon in the mode area will turn
on.

73,
matt, W6NIA

On Sun, 03 Aug 2008 23:15:47 +0100, you wrote:

>Hi all,
>Out of interest I thought I would try the new feature.  I only have the 
>2.7kHz filter but people noticed the difference when I swtched.  I did 
>however get a ERR TXF message when I switch it on and TX.  it transmits 
>OK but gives the message.  Anyone else seeing this?
>
>73 Ian