[Elecraft] Swapping Standard 2.7 kHz 5-pole Filter

Doug Faunt N6TQS +1-510-655-8604 faunt at panix.com
Fri Jun 29 01:17:30 EDT 2007


   Date: Thu, 28 Jun 2007 21:20:26 -0700
   From: "Eric Swartz - WA6HHQ, Elecraft" <eric at elecraft.com>

   Hi Bill,

   This is incorrect. The 2.7 kHz 5-pole can only be swapped for a 2.8 kHz 
   or possibly the 2.1 kHz 8 pole filters. We require at least one SSB b/w 
   filter in each K3 as it ships since we must also transmit through the 
   filter for SSB and data modes. Transmitting through the 2.1 kHz filter 
   will limit your tx bandwidth to that value. ( I'm not aware of many 
   choosing the 2.1 as their only SSB filter - I may drop that as a swap 
   option to make sure no overly narrow TX K3s get out there and confuse 
   the market.)

Is 2.1kHz really overly narrow for SSB transmit?  I know people are
talking about 1.8kHz filters for RX, and it seems useless to transmit
energy that's not going to be used.  It's certainly wide enough for
data modes.  In fact, it might be useful to be able to TX through the
400Hz filter in some of those modes.

73, doug


More information about the Elecraft mailing list