[Elecraft] Hearing the effect of narrower roofing filter

[Darwin, Keith]

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Erik N Basilier

My K3 ... interesting to do an A/B comparison to see how the receiver
sounds with/without the narrow crystal filter for a given bandwidth.

...

What has been observed by the group?
---------------------------

I've not attempted such a complex test as you described (which I snipped
out).  I have the 500 Hz filter in my rig.  As I narrow the DSP from 2
KHz to 550 Hz, I can hear a predictable narrowing of the passband with
each step.  When I step to 500 Hz and the narrow roofing filter kicks
in, I can hear a distinct change, more than just the DSP narrowing I'd
heard while stepping from 1000 Hz to 550 Hz.  The effect is very
noticeable.  I don't think you'd have to construct some sort of
(artificial) double-blind test to see what it does.  Besides, what you
really want to know is how does it play on the air.  The best way to
learn that is to play on the air :-)

I have been able to get AGC pumping if I try.  In all cases, going from
550 Hz to 500 Hz bandwidth took care of the pumping (roofing filter
works)

- Keith N1AS -
- K3 711 -