Tektronix CURVE-TRACER 576 Instruction Manual page 179

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b. Set the Calibration Fixture Function switch to Verti·
cal Current Check.
c. Press the ZERO button and position the spot on the
center horizontal line. Release the ZERO button.
d. Turn the VARIABLE COLLECTOR SUPPLY control
fully clockwise.
e. CHECK FOR-Spot on the center horizontal grati-
cule line ±2 divisions (±2%).
f. Set the Type 576 CENTERLINE VALUE switch to
10.
g. Turn the Type 576 VERTICAL switch and the Cali-
bration Fixture Vertical switch, together, throughout their
ranges.
h. CHECK FOR-Spot on center horizontal graticule
line ±2 divisions (±2%) for all positions of the VERTICAL
switch. On high sensitivity positions, adjust the intensity
until 2 spots appear. Then, momentarily turn the VARI-
ABLE COLLECTOR SUPPLY control counterclockwise to
obtain a single spot.
i. Set the following Type 576 controls as listed:
VERTICAL
MODE
STEPS
5 pA EMITTER
LEAKAGE (EMITTER
CURRENT)
Pressed
j. Set the Calibration Fixture Vertical control to 50 pA.
k. Turn the Type 576 VERTICAL switch and the Cali-
bration Fixture Vertical switch, together clockwise
throughout their ranges.
I. CHECK FOR-Spot on center horizontal graticule line
±2 divisions ±1 nA (±2% ±1 nA) for all positions of the
Type 576 VERTICAL switch except the 1 nA, 2 nA and 5
nA positions. In these positions set the DISPLAY OFFSET
Selector switch to NORM (OFF) and check that the spot is
on the tenth horizontal graticule line ±0.5 division ±1 nA
(±5% ±1 nA).
ADD AUG 1984
Performance Check-Type 576
m. Set the following Type 576 controls to:
VERTICAL
VARIABLE COLLECTOR
SUPPLY
MODE
STEP FAMILY
STEP GEN
Fully Counterclockwise
NORM
REP
n. CHECK FOR-11 spots displayed vertically with the
first spot on the zero horizontal graticule line and the
eleventh on the tenth horizontal graticule line ±0.4 division
(±4%).
Control Settings (Partial List)
INTENSITY
FOCUS
VERTICAL
POLARITY
OFFSET MULT
STEP FAMILY
Type 576
Visible Spot
Smallest Spot Possible
STEP GEN
+(NPN)
10.0
REP
6. Check Miscellaneous Step Generator Buttons
a. Set the Type 576 and Calibration Fixture controls as
shown in the list of Initial Control Settings with changes as
shown in the preceding partial list.
b. Turn the NUMBER OF STEPS switch counterclock-
wise throughout its range.
c. CHECK FOR-Number of spots decreasing by one for
each position of the switch. At one step there should be 2
spots.
d. Turn the vertical POSITION switch two pos1t10ns
clockwise and press the POLARITY INVERT button. Turn
the NUMBER OF STEPS switch clockwise throughout its
range.
e. CHECK FOR-Inverted step generator output with
zero step on tenth horizontal graticule line.
f. Set the following Type 576 controls as listed:
Vertical POSITION
POLARITY INVERT
RATE
Centered
Released
.5X
g. Note the rate at which steps are being generated then
press the NORM RATE and 2X RATE buttons.
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