[NLRS] Where to put interdigital filter?

[Scott]

I'm building up one of W1GHZ's cheap transverters for 1296 to use while 
roving.  Output from this transverter board is 10 to 20 mW.  I will use 
this to drive an RF brick module (such as the M67715), resulting in an 
output of 1 to 2 Watts.  I plan to use a 5 rod interdigital filter cut 
for 1296 as per the plans in the ARRL "UHF/Microwave Projects Manual 
Volume 1" page 6-2.  I had originally thought I would put it between the 
antenna and the "common TX/RX" antenna jack.  My intention was to 
provide some filtering on the RX side as there isn't any filtering 
before the first RF amp on the board (INA-10386).  The only 1296 filter 
in this transverter is a single etched filter on the board, common to 
both TX and RX.  I read somewhere that my idea might not be good to have 
the interdigital filter in line before the RF amp as it will increase 
NF.  So, should I place the filter so that it is only in the TX path 
(after the RF module)?

-- 
Scott N0EDV
http://corbenflyer.tripod.com/
Flying Corben Junior Ace - Building RV-4
Gotta Fly or Gonna Die