The following data for the Collins 75A-4 were presented in a talk at the 1979
W9DXCC Meeting and are attributed to Bob Sherwood.
Measurements done at 500 hz bandwidth.
Noise floor: -143.5 dBm
Intermodulation:
@20 Khz
dynamic range: 66 dB
3rd order intercept: -44.5 dBm
@2 Khz
Dynamic range: tone
3rd order intercept: -- (I think this means it couldn't be measured)
Blocking dynamic range:
@ 20 Khz: 95 dB
@ 2 Khz: tone
Sideband noise:
Level below the noise floor:
@ 20 Khz: blocking
@ 2 Khz: tone
AGC range:
0 to -100 dBm, input dB: 1.5
As you can see, the intermod and blocking characteristics are not very good,
especially at close spacing.
Best wishes,
Jim, K9RJ
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