[Elecraft] Filter Selection Approach

[Joe Subich, W4TV]

That is a lot of filters ... 

1) The DSP is quite effective and there is not much difference 
   (if any) in the performance of the 2.8 KHz 8-pole filter vs. 
   the 2.7 KHz 5-pole filters.  Even if one pays the extra $30 
   for a matched pair of 2.7 KHz filters, the added cost of the 
   2.8 KHz pair is $180.00 

2) Unless you are in very heavy QRM/pile-up situations the 
   roofing filter does not provide a lot of "value added" 
   since the final bandwidth is determined by the DSP.  The 
   1 KHz filters add little benefit vs. the 1.8 KHz or 1.5 
   KHz filters.  

3) The 13 KHz filter can be used for AM receive - there is 
   no benefit in having both the 13 and 6 KHz filters in the 
   sub RX.  It is a shame that Elecraft still do not permit 
   use of the 13 KHz for AM and ESSB transmit (even if it 
   were offset 3 KHz in transmit for additional image rejection). 

A less expensive line-up that seems to provide maximum 
(IMO) flexibility/performance is:  
  Main:  13 - 2.7 - 1.8 (1.5) - 400 - 200 
  Sub:   13 - 2.7 - 400 

73, 

   ... Joe, W4TV 
 


> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Ed G
> Sent: Monday, April 13, 2009 7:24 PM
> To: elecraft at mailman.qth.net
> Subject: [Elecraft] Filter Selection Approach
> 
> 
> Hello,
>      I am getting ready to order a K3 with subreceiver soon, 
> and have been thinking about which filters to order.  From 
> most of what I read, folks seem to order duplicates for the 
> subreceiver of what they have ordered for the main receiver, 
> or perhaps just go with just a couple narrower ones for the 
> subreceiver. Since I work mostly CW, and am not too 
> interested in diversity reception (don't have the antennas 
> either), I was thinking of the following:
> 
> Main Rx: 2.8 - 1.8 - 1 - 400 - 200
> Sub Rx: 13 - 6 - 2.8 - 2.1 - 1 or 400
> 
> I know that's a lot of filters, but other than going broke, 
> are there any drawbacks to this? Has anyone else tried to 
> essentially give themselves all the filter options by 
> populating both receivers with different filters?
> 
> --Ed--
>