I have a ic 737 so its an
old fashioned "don't got any dsp" radio so the 599zx has
been very useful to me.
The effectivenss of these "toys" become very personal
as they help or hurt the individual operators ability
to hear the unhearable.... the weak one 3db below the
noise he needs for a new one. I can say my 599zx has
comes into play about 1/2 the time I work a new one,
but again, I don't have a fancy radio with a lot of
knobs to twist.
Two days ago, I copied 9M2MX for the first time at my
QTH. Near solid copy with the 599zx in the spotlight
mode down to 10 hz. Switched spotlight off and the
ringing forced me to back off to about 100hz. Bottom
line was about 80% copy with 10hz and spotlight
(workable) 30% copy without (ESP possible).
The effectiveness of the filter I notice is also
related to the characteristics of the background
noise. At times I have almost white noise in the
background. At these times I can crank the BW down to
40-50 hz. When my background noise is raspy, I may
only be able to go down to 150 hz. The difference is
the ringing that is generated by the characteristics
of the background noise. I seem to be finding that the
spotlight mode modifies the slope (poor shape factor)
of the skirts away from the center FQ, and sharpens it
near the center FQ. This apparently reduces the
ringing. Clever idea actually. Bottom line, I can use
the narrow BW even when my background noise is raspy.
To get it go their web page
http://www.timewave.com/
all the info you need is there. I called on the phone
and they had the new rom to me in about a week. You
will need to give them your serial number so they know
what software to send. The upgrade is $60 US. plus
shipping.
Greg
W7MY
--
FAQ on WWW: http://www.contesting.com/FAQ/topband
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Problems: owner-topband@contesting.com
|