Yaesu FT-2000D, Operating Manual

Page: 76 / 140

Page 74 FT-2000D O
PERATING
M
ANUAL
E
NHANCING
T
RANSMIT
S
IGNAL
Q
UALITY
L
OW
- D
ISTORTION
CLASS-A O
PERATION
(
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 - 100 0 - 100 0 - 100 0 - 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 “
100 100 100 100 100
” 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
“
Ab Ab Ab Ab 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 “
Ab Ab Ab Ab Ab
” in
step 3 above.
Main Tuning Dial Knob
[SUB VFO-B] Knob
[MENU] Button
CLASS-AB CLASS-A
Id: Drain Current
V
DS
: Drain Voltage
A
DVICE
We recommend that menu item “ 143 tGEn BIAS ” be pro-
grammed to the [ C.S
] button for easy access to Class-A
operation.