Low- Distortion Class-A Operation - Yaesu FT-2000 Operating Manual

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NHANCING
L
OW
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
"141 tGEn BIAS."
3. Rotate the [ SUB VFO-B ] knob to select the desired
BIAS level "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" 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" 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" in
step 3 above.
CLASS-AB
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RANSMIT
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ISTORTION
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IGNAL
PERATION SSB M
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A
We recommend that menu item "141 tGEn BIAS" be pro-
grammed to the [ C.S ] button for easy access to Class-A
operation.
: Drain Voltage
FT-2000D O
UALITY
[ MENU ] Button
[ SUB VFO-B ] Knob
Main Tuning Dial Knob
CLASS-A
M