User's Manual

ALPHA 9500 Interim OPERATING MANUAL
www.alpharadioproducts.com
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RF POWER kW These LEDs display the forward power
SWR These LEDs display the SWR seen by the amplifier
GRID CURRENT This bar graph shows the grid current in mA
PLATE
CURRENT
This bargraph shows the plate current in amps
PLATE VOLTAGE This bargraph shows the plate voltage in kV
GAIN This set of LEDs shows the gain of the amp in dB
Fwd The numbers displayed in the seven segment display are controlled by the
settings of the switches below the display. This switch sets the display to
forward power in watts
Ip This switch sets the display to plate current in mA
Vp This switch sets the display to plate voltage in kV
Ig This switch sets the display to grid current in mA
SWR This switch sets the display to show SWR
FLT This switch sets the display to show the last Fault
DIM This switch controls the brightness of the display LEDs
SND This switch controls the sound volume (not yet implemented)
PEP This switch toggles between PEP mode and carrier/tune mode
DEL This switch controls the Delivered power function
OPER Operate position
STBY Standby (bypass) condition
ON(AMP) Amplifier on
ON/OFF(ANT
SEL)
Antenna select on - tubes not on
6.3.2 Tune-Up
The objective of tune-up is to adjust the amplifier (and the drive applied to it) to obtain optimum
efficiency and linearity at the desired output power. Any linear amplifier must be adjusted for
optimum efficiency and linearity at each specific power level. If operation at higher power
is then attempted without appropriate readjustment, the result will be flattopping, “splatter,”
and (usually) excessive amplifier grid current. If operated at a much lower power level than it
has been adjusted for, the amplifier’s efficiency decreases considerably. Alpha Radio Products
makes the ALPHA 2100 in-line dummy load which simplifies this process. Using the AP 2100, the