Yaesu FT-2000D - Low- Distortion CLASS-A Operation

Page 74 FT-2000D OPERATING MANUAL
ENHANCING TRANSMIT SIGNAL QUALITY
LOW- DISTORTION CLASS-A OPERATION
(
SSB M
ODE
)
Class-A operation of the FT-2000D transmitter is provided, yielding ultra-low distortion products during SSB operation.
Power output during Class-A operation is 75 Watts.
To engage Class-A operation as following:
1. Press the
[
MENU
]
button; the Menu list will appear in
the display.
2. Rotate the Main Tuning Dial knob to select Menu item
“143 tGEn BIAS.”
3. Rotate the
[
SUB VFO-B
]
knob to select the desired
BIAS level “
0 - 1000 - 100
0 - 1000 - 100
0 - 100” to set the transceiver for opera-
tion anywhere between Class-A and Class-AB (Class-
AB has lower heat dissipation but higher distortion
products).
Rotate the
[
SUB VFO-B
]
knob clockwise to increases
the BIAS. A menu setting of “
100100
100100
100” will place the trans-
mitter fully in Class-A operation. Counter-clockwise
rotation of the
[
SUB VFO-B
]
knob will move the trans-
mitter toward Class-AB operation. The menu setting
“
AbAb
AbAb
Ab” will place the transmitter fully in Class-AB op-
eration.
Advice:
When the Class-A operation is engaged, “ ”
icon will appear in the display.
4. Press and hold in the
[
MENU
]
button for two seconds
to save the new setting and exit to normal operation.
To exit from the Class-A mode, repeat the above proce-
dure, rotating the
[
SUB VFO-B
]
knob to select “
AbAb
AbAb
Ab” in
step 3 above.
Main Tuning Dial Knob
[
SUB VFO-B
]
Knob
[
MENU
]
Button
CLASS-AB CLASS-A
Id: Drain Current
VDS: Drain Voltage
ADVICE
We recommend that menu item “143 tGEn BIAS” be pro-
grammed to the
[
C.S
]
button for easy access to Class-A
operation.