[1000mp] MP Roofing Filter from INRAD

[k6se at juno.com]

Pete, N4ZR wrote:

"I've got to say that even on 10 meters, I have never noticed the
difference in background hiss on my Mark V since installing the mod (once
I adjusted the IF gain per recommendation).  With my antennas, there is a
 noticeable drop in noise when I disconnect the antenna input, so I can't
see where the hiss reduction is an issue here.  I can reliably hear
people who are far too weak even to make the S-meter start to indicate. 
I suspect this hiss is more an issue for people using MPs with
transverters or people in super-quiet locations."
==========
I live in a super-noisy location and my MP's IF hiss was quite
noticeable.  Be aware that the hiss is there only in the CW mode and with
the EDSP turned off.  Narrow filters (250 Hz) make it even more
pronounced.

The INRAD front end mod reduces the hiss, but not quite enough.  The
bonus capacitor that George provides with the mod makes a bigger
difference.  The mod and the bonus capacitor together is what is
necessary to reduce the hiss to where it is negligible.

73, de Earl, K6SE