Tektronix 570, Руководство пользователя

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Ig
J
.5
MA/DN
o
Egl
20 VOL TS/DIV
E-
P
Control Senings for Pentode section of
a
6U8
PEAK VOLTS
200
SERIES LOAD
10k
STEPS/SEC
240
VOLTS/STEP
. 1
START ADJUST
full clockwise
PLATE-GRID
PLATE
PLATE-SCREEN-GRID
GRID
MA/DIV
.5
VOLTS/DIV
20
+DC
5
0
+DC VARIABLE
Set for
ZJ
volts
Fig. 2-10. Gr
i
d Current vs.
P
l
a
te Voltage curves for
the pemode
section of a
6US.
Screen Current
vs.
Plate Voltage
This curve can be plotted by setting the
controls as for the plate current versus plate
voltage display with the exception that the
P L ATE-SC REEN-G RID Control is set to
SC REEN. If switching lines interfere with the
display at the left, the STEPS/SEC Control
should be moved to the right hand
120
position.
Screen Current
vs.
Grid Voltage
This curve is similar to the plate current
versus grid voltage curve. It is obtained by
s etting the PLATE-SC REEN-G RID Control to
SC REEN and the PLATE - G RID Control to G RID.
Adjust the HO RIZONTAL VOL TS/DIV as re­
quired to obtain a full screen display and
position the display as desired. If the STEPS/
S EC control is set to the right hand position
the SWitching lines will form a continuous curve
indicating the screen current at maximum plate
voltage as set by the PEAK VOLTS Control.
The vertical lines represent the variation of
s creen current as the plate voltage is swept
from zero to maximum.
-.05
+.75 +.95
o Egl
+.25
+.
5
+. 5
1
MA/ DIV
.1
VOLTS/DIV
Egi
Control Settings for Pentode section of
a
6
U
8
PEAK VOLTS
SERIES LOAD
STEPS/SEC
VOLTS/STEP
START ADJUST
PLATE -GRID
PLATE -SCREEN -GRID
MA/DIV
VOLTS/DIV
+DC
+
DC VARIABLE
200
10k
240
. 1
full clockwise
GRID
PLATE
1
. 1
5
0
Set for
45
volts
Fig. 2-11.
Plate Current
vs.
G rid VOltage curves
for
the pemode
section of a
6US.
SINGLE-FAMilY DISPLAY
Characteristics of a tube in the region where
its power rating is exceeded can be obtained
by means of the single- family feature. When
this feature is used, the grid is held negative
until the SINGLE F AMIL Y button is pushed, at
which time it runs through one family of curves
and again stops with the grid negative.
To use this feature . first set up the controls to
plot a family of curves that is within the safe
operating limits of the tube.
Then turn the
STEPS/F AMIL Y Control clockwise to the stop.
Make the desired changes to the operating and
generator voltages. As these adjustments are
b eing made push the SINGLE F AMIL Y button
occasionally to determine the operating point
that has been reached. When the desired
operating point is reached push the SINGLE
F AMILY button to obtain the single display.
The maximum voltage swing from the Grid­
Step Generator as it plots a family of curves
AA
Operating Instructions - Type
570 2-9