HF Transceivers performance comparison 
The March 2000 issue of RadCom has an in depth technical review of the new ICOM  
IC756 PRO.  I have summarized three key technical measurements on  a variety of 
transceivers, all made by the same reviewer, Peter Hart, using the same 
methodology.    
The three  measurements are the  two-tone dynamic range (in a SSB bandwidth), a 
reciprocal  mixing measure, and the amount of transmitter broadband noise (also 
in  a SSB bandwidth).  The rigs are listed with the best at the top in terms of 
close-in performance. The IC756 PRO ranks near the bottom.
Spacing         3k      5k      10k     15k     20k     30k  
Corsair I - November 1984 - no synthesizers 
DR               -      90      90      90      90      90
Recip            -      98      98      98      98      98
TX noise        95      95      95      95      95      95  
OMNI-VI - January 1994 
DR              88      88      88      88      88      88
Recip           86      86      -       96      96      96
TX noise        83      87      96      97      98      98
FT1000MP - January 1996
DR              78      82      92     103      99      98
Recip           80      86      94      99     103     108
TX noise        76      81      89      94      96      99
IC737 - September 1993
DR              74      80      88      92      94      98
Recip           90      96     104     105     107     110
TX noise        79      87      93      95      96      97
FT990 - April 1992
DR              70      78      88      92      94      96
Recip           83      87      93      97     100     105
TX noise        74      79      84      86      87      88
TS690S - November 1992
DR              67      77      87      91      93      94
Recip           -       -       -       98     101     105
TX noise        70      77      82      85      88      88
TS930 - May 1986
DR              -       77      87      -       91      92
Recip           77      83      89      -       97     101
TX noise        -       79      83      -       85      88
TS940 (with Lowe modification to improve reciprocal mixing by 12db)
        - May 1986
DR              -       76      81      -       88      91
Recip           83      89      98      -      105     110
TX noise        -       72      72      -       72      74
TS850 - October 1991
DR              -       75      89      95      95      96
Recip           85      89     100     105     108     112
TX noise        75      83      90      95      96      99
IC756 - May 1997
DR              74      74      75      79      82      86
Recip           79      84      91      95      98     102
TX noise        73      80      87      91      94      97
IC756 PRO - March 2000
DR              72      73      76      82      86      90
Recip           83      86      92      96      98     101
TX noise        -       -       -       -       -       -       
IC775DSP - January 1996
DR              72      72      78      87      91      93
Recip           90      96     100     103     106     109
TX noise        78      80      87      92      97     100
FT920 - August 1997
DR              70      72      83      95      97      96
Recip           85      90      97     101     104     108
TX noise        -       -       -       -       -       -
TS50S - May 1993
DR              67      69      74      80      84      92
Recip           78      84      95      -      103     104
TX noise        74      79      85      90      93      97
FT847 - August 1998
DR              65      67      78      89      96      94
Recip           76      80      90      94      97     101
TX noise        70      76      86      90      93      97
FT1000 - June 1991
DR              65      65      72      82      88      93
Recip           81      85      91      95      98     102
TX noise        -       76      81      -       84      -
TS870 - April 1996
DR              58      61      73      84      94      95
Recip           -       -       -      100     103     107
TX noise        75      80      88      91      92      93
IC781 - July 1990
DR              52      57      76      92      97      -
Recip           90      96     103     106     110     113
TX noise        -       85      92      -       98      -
Notes:
DR      - two-tone dynamic range on 7 MHz in SSB bandwidth
Recip   - reciprocal mixing for 3dB increase in receiver noise
TX noise- dBC in 2.5kHz bandwidth
spacings refers to spacing of the two tones for dynamic range and
the offset from the carrier frequency for reciprocal mixing and
TX noise
Dates refer to issues of RadCom containing the Peter Hart review.
Rigs listed in order of decreasing dynamic range with 5 kHz spacing.

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OK1VPZ Comment to the HF transceivers performance chart:

In our praxis for more precise calculation (not as in the list shown noise performance for SSB filter) is used noise performance for 1 Hz unit. (1 Hz of filter bandwidth).

So for ordinary use add to the (in chart) submitted noise (reciprocal mixing and TX noise) performance + 34 dB (2.5 kHz SSB filter is 34 dB wider than 1 Hz). After that you will get the result in dBc/Hz units.

(For example - FT 1000 MP has in 20 kHz space from carrier aprox. - 137 dBc/Hz local oscillator sideband noise and 130 dBc/Hz overall TX noise).

Because in this issue were not described noise spectrum of test oscillator and methodology of measurment, results are a bit uncertain from the perspective of absolute values. But in any case it is good help, how compare those transceivers each to other.