[1000mp] MP Roofing Filter from INRAD

[Pete Smith]

At 09:02 AM 5/18/2004, you wrote:
>suspect, but did not have time to question George on the
>matter, that the 2 dB gain figure was a compromise between a
>little noise reduction and IMD.  I figure that one can use
>the radio's DSP or an external filter (even a relatively
>simple passive analog filter) to remove the hiss if it is
>too objectionable.  There is no way to remove the IMD once
>the second mixer gets crunched.


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.


73, Pete N4ZR
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