Yaesu FT DX 9000 CONTEST Operation Manual page 87

SSB/AM M SSB/AM M SSB/AM M
SSB/AM M SSB/AM M
L
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
transmitter means that these intermodulation distortion products will not exist to be amplified by your linear.
High-Power 200-Watt Final Amplifier Stage
The final amplifier stage of the FT
MOSFET devices operating at 50 Volts. This 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.
FT 9000 C O
DX ONTEST
T T T T T
RANSMISSION ( L L L L L
ODE ODE ODE RANSMISSION RANSMISSION
ODE ODE RANSMISSION RANSMISSION
- D CLASS-A O
OW ISTORTION
Continuous adjustment of the
Bias Level between Class-A
and Class-AB is possible.
Class-AB
Class-AB and Class-A Operating Principle
Q
UICK
9000 Contest utilizes a pair of ST Micro Electronics Corp. SD2931
DX
M
PERATION ANUAL
- D - D - D - D - D
O O O O O W W W W W IST IST IST IST ISTOR OR OR OR ORTION TION TION TION
TION
PERATION
Class-A
P
OINT
)
CLASS-A O CLASS-A O CLASS-A O
CLASS-A O CLASS-A O
PERA PERATION PERA TION TION TION
PERA PERA TION
Input
9000 Contest's
DX
Page 85