Graphic Meter Display - Yaesu FTDX9000 - DATA MANAGEMENT Operation Manual

VDD
The drain voltage of the final FET is measured
and displayed here. The measurement range is
0-60 V, and the proper voltage is around 50 V.
On TX, if around 50 V is displayed, the transceiver
is operating normally.
BIAS
While operating with the Class-A, and the bias is
changed by rotating the BIAS knob from class A
to class AB, this indication can be used to ob-
serve the current setting. The indication is 0-100
% and "0%" means class AB, while "100%" means
class A.
Even if the Bias is varied, the RF output will not
change (up to the 75 Watts (Contest) or 100W
(MP) of maximum power under class A), and you
can change the bias safely even when you are
using a linear amplifier.
FT 9000MP/C
DX ONTEST
T
EMPERATURE
G M
RAPHIC
D M
ATA ANAGEMENT
/ SWR I
D
ETER ISPLAYS
TEMP
This indicates the temperature (measured) of the
final amplifier FETs' heat sink.
The measured temperature range of this meter
is 0 - 100 °C, and above 80 °C is the "Red Zone"
temperature range to be avoided, so as to en-
sure a safe operating temperature range. When
the temperature rises above 80 °C, the fan speed
will increase by a factor of four, providing a sig-
nificant increase in air flow. The heat sink tem-
perature may rise appreciably during Class-A op-
eration, especially if the ambient temperature is
warm, and we recommend that you monitor the
temperature during Class-A transmission, adjust-
ing the Bias control downward (more toward
Class AB) if excessive heating is observed. A
lower bias level will cause less heat to be dissi-
pated, thus reducing the heat sink temperature.
SWR
This displays the SWR characteristic of the ama-
teur band that you are currently using, with points
along the graph indicating the frequencies that
have been measured.
O M
PERATION ANUAL
NDICATION
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