[Yaesu] FT897 Review-kind of confusing

[John Geiger]

Was happy to hear that the FT897 review was up on the
ARRL website, as I have been interested in this radio.
 After reading it, I dont think that I will be
replacing my FT100D with it anytime soon.  Yes the
clamp on tuner and built in PS would be nice, and the
extra CW keyer memories would also be nice, but that
is about it.  I spoke with a couple of Yaesu
representatives at hamcomm last year about the FT897,
and they said that the receiver performance would be
about equal to the FT920.  If the ARRL numbers are
right, that was a great overstatement.

Here is the most confusing statement in the QST
review:

"The two-tone, third-order IMD dynamic range comes in
at about 90db at 20 khz signal spacing and the preamp
off.  When the spacing drops to 5 khz, the IMD DR
measurement drops to around 67 db.  Compare this 5 khz
measurement to Yaesu's other recent 100 W radio with a
handle, the high-end and much heavier FT1000 MP Mark V
Field, and you will find similar performance.  For a
radio of its price class, the FT-897 does a very nice
job of pulling out the weak ones in the presence of
strong ones."


Well, I didn't believe that bit about the 5 khz DR
being comparable to the FT1000 MP MKV, so I went and
looked at that review. Here is the actual comparison"

                       80m            20m
Preamp             OFF     ON      OFF     ON

FT897              68      67      67      65
FT1000MP MKV       69      74      73      72

I am not sure that those numbers are that comparable. 
For both bands with the preamp on the difference is
7DB, as the difference on 20 with the preamp off is
6DB.  The Blocking DR difference at 5khz is 10 db or
more, and the 3rd order IP difference is huge.  

With these differences, how in the world can the ARRL
say that these rigs show similar performance?  What am
I missing?  When the Kenwood TS2000 was first
reviewed, and the ARRL started the 5khz testing, its
3rd IMD at 5 khz came in at 69db, and everyone started
slamming it for having the worst performance ever on
that measure.  It did come out better than the FT897
in that respect. 

Unfortunately the ARRL did not do a 5KHZ testing on
the FT100, but look at the numbers for the FT100 vs
FT897 at 20khz.

                    Blocking DR

              80m             20m            6m
Preamp     off    on      off      on     off     on
FT100     128    121     130       125    116    107
FT897     111    109     109       106    116    107

                    3rd IMD DR

              80m             20m            6m
Preamp     off    on      off      on     off     on
FT100      92     88      94       91      94     90  
FT897      91     90      89       86      89     95


                    3rd order IP

              80m             20m            6m
Preamp     off    on      off      on     off     on
FT100      6.3   -5.7     10       4.2     20    1.2  
FT897      5.6   -1.9    1.3      -6.7    -3.5   -12


I think the numbers speak for themselves.  I will keep
the FT100D over the FT897.  In fact, the numbers for
the FT897 are worse than the numbers for the FT847 in
many areas, and I didn't think that was possible.

73s John NE0P   






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