[Elecraft] K3 Noise Blanker ahead or behind roofing filter?

[Kenneth A. Christiansen]

I have K2 SN 1031 and an IC-746PRO. Last week my next door neighbor 
brought home a large screen TV that looks to be the rear projection 
type. I didn't pay much attention to it as they unloaded it but now find 
it puts out lots of QRN. It  puts out S9 on the PRO 60 HZ QRN on 20, 15, 
10 6 and 2 meters. Those are the bands I have antennas that work. The 
noise blanker in theK2 and the PRO both eliminate this bad QRN right 
down to the background noise :-)  when there are now strong signals on 
the band but when a strong station such as the W1AW code sessions come 
on 20 meters, (20 over 9 in ND), than the K2 using NB1 has problems 5 
KHZ or so either side of W1AW. NB2 has problems up to 10 KHZ either side 
of W1AW and the PRO has problems 15 KHZ either side of W1AW :-( . Is the 
noise blanker on the K3 ahead of the roofing filter or behind the 
roofing filter. If it is behind the roofing filter buying a K3 might put 
me back on the air :-)      but if it is ahead of the roofing filter 
than would I have the same problem as the K2 :-( ? I have looked at the 
FAQ part of the Elecraft K3 site and do not find the answer to this 
question. I just need a short answer so please do not start a long 
thread on my station or observations etc.

73 and thanks for the help.

W0CZ