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[CQ-Contest] What am I Missing

To: CQ-Contest@contesting.com
Subject: [CQ-Contest] What am I Missing
From: Pete Smith <pete.n4zr@gmail.com>
Date: Tue, 28 Feb 2006 10:47:52 -0500
List-post: <mailto:cq-contest@contesting.com>
I am perplexed.  After reading the review of the FTDX9000 Contest in the March 
QST, I can't imagine why a contester would buy one of these, even given the 
adoring subjective comments by the ARRL reviewers.  For the $5700 basic price, 
you could buy 2 or 3 MPs loaded with Inrad filters.  Combine that with Yaesu's 
policy of requiring you to buy any options at the time of purchase (meaning 
either huge, expensive stocks or a long wait), and I think the market for used 
MPs will be in good shape for a long time.   

Just for fun, I compared the ARRL Lab's receiver performance stats for the 9000 
Contest with those for two different MPs with the Inrad roofing filter.  Aside 
from third-order intercept, not stated in the ARRL's MP/roofing filter review, 
both MPs walk all over the 9000 in almost all of the parameters of particular 
interest to us.  The third-order intercept for a stock Mark 5 field at 5 kHz 
spacing is pretty low; at 20 KHz it is comparable to the 9000's at 5 KHz.  it 
would be interesting to know what difference the roofing filter would make in 
this measurement.

View the table below with a monospaced font for best results:

                                MkV/1000MP                              
FTdx9000 Contest
Data taken on 20 meters 
with pre-amp off

Noise Floor                     ?130 dBm/-126 dBm                       -123 dBm

Blocking Dynamic Range          20 kHz   146 dB*/141 dB                 128 dB*
                                5 kHz    130 dB*/128 dB                 119 dB*
                                2 kHz    105 dB/108 dB                   97 dB
                                1 kHz    106 dB(1)/103 dB*              Not 
stated

IMD Dynamic Range               20 kHz 93 dB/100 dB                     101 dB
                                5 kHz  89 dB*/90 dB*                     98 dB*
                                2 kHz  79 dB*/71 dB                      78 dB* 
                
                                1 kHz  69 dB*/68 dB*                    Not 
stated

*Measurement was noise limited at the value indicated.
(1) Some filter blow-by was noted on this measurement.


73, Pete N4ZR


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