Yaesu VL-1000, Technical Supplement

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VL-1000 Technical Supplement
Alignment
Forward ALC Adjustment (High Power)
Ì
Tune the transceiver to 14.050 MHz, FM mode,
and set the DRIVE or RF PWR control fully
clockwise.
Ì
Press and hold in the INPUT switch on the front
panel of the VL-1000 for ½ second. This initiates
the “ALC Alignment” mode.
Ì
Start with the transceiver’s DRIVE or RF PWR
control fully counter-clockwise, then rotate the
DRIVE or RF PWR control to the fully clock-
wise position while transmitting.
Ì
If the power output from the amplifier (as dis-
played on the AVG PWR meter) does not reach
1000 W because of the effect of the VL-1000’s ALC
voltage at full excited drive, keep the transceiv-
er’s DRIVE or RF PWR control fully clockwise,
then press and hold in the DISPLAY 2 key until
the power output from the amplifier reaches 1000
Watts.
Ì
If, on the other hand, the ALC voltage from the
VL-1000 does not cause the exciter drive to be
controlled such that the power output from the
amplifier limits at 1000 Watts, reduce the setting
of the DRIVE or RF PWR control to that the out-
put power is 1000 Watts. Now press and hold in
the DISPLAY 2 key until you observe the ampli-
fier output just begin to fall below 1000 Watts. At
this point, advance the DRIVE or RF PWR con-
trol fully clockwise, and press/hold in the DIS-
PLAY 1 or DISPLAY 2 key so as to achieve 1000
Watts of power output.
Ì
If the above adjustments are not successful, it is
possible that the Forward ALC potentiometer,
VR1001, is maladjusted. While transmitting,
slowly rotate VR1001 in the direction that pro-
vides improved output control (either more or
less ALC voltage, as observed on the transceiv-
er’s ALC meter). When 1000 Watts of output
VR5004: Idling Current (800 mA)
VR5003: Idling Current (610 mA)
VR5002: Idling Current (800 mA)
VR5001: Idling Current (610 mA)
J5001: Remove this wire when adjusting the other PA Unit
J5007: Remove this wire when adjusting the other PA Unit
PA Unit Alignment Points