[Elecraft] KFL1-4, Deaf on 40m, K1 SN# 150

[Mike]

I finished my KFL1-4 board tonight.  All resistance check seem okay.  
Started to peak the filters.I use my other rig at low power into a dummy 
load for the signal.
30 meters peaked up fine.  Signal was very close to where it was 
supposed to be.
40 meters couldn't even find a signal.  Went to next went to 15m .  It 
peaked fine.  
I did notice that the screwdriver I was using acted like an antenna when 
I got near CA
one of the RF trimmers for 20. Didn't do that on any of the others.  
Then went to 20 it peaked fine.

Back to 40 and still no luck.  

Any suggestions of what could be the problem?  I had used two band board 
in the rig
with no problem.  The 20/40 was in use before I installed the new 4 band 
filter board.  

Any help would be appreciated.  

73,

Mike KB4WJA