[CQ-Contest] What am I Missing
pete.n4zr at gmail.com
Tue Feb 28 10:47:52 EST 2006
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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