Operation Manual

Page 93FT DX 9000MP OPERATION MANUAL
SSB/AM M ODE T RANSMISSION (LOW- DISTORTION CLASS-A OPERATION)
Quick Point
 Class-A operation provides a significant improvement in transmitter distortion suppression. During Class-A, the 3rd-
order IMD products are typically suppressed 50 dB, while the 5th- and higher-order IMD products (that can cause
“splatter” that interferes with others) will typically be suppressed 70 dB or more.
 If you are using a linear amplifier such as the VL-1000, the low distortion produced by the FT DX 9000MP’s transmitter
means that these intermodulation distortion products will not exist to be amplified by your linear.
 High-Power 400-Watt Final Amplifier Stage
The final amplifier stage of the FT DX 9000MP utilizes a parallel pair of ST Micro Electronics Corp. SD2931 MOSFET
devices operating at 50 Volts. This parallel push-pull configuration provides low distortion along with high power
output. The 120 mm thermostatically-controlled cooling fan directs forced air across the heat sink, should the heat sink
temperature exceed the temperature that will trigger the thermostat.
LOW- DISTORTION CLASS-A OPERATION