Adjust Vertical High-Frequency Compensation - Tektronix 7623A Instruction Manual

Calibration--7623A/R7623A Service
e. Set the signal standardizer Position control to center the trace while adjusting the Amplitude
control for a two-division display.
f. CHECK--Position the two-division display vertically and check for not more than 0.1 division
of compression or expansion anywhere within the graticule area.
5. Adjust Vertical High-Frequency Compensation
a. Install the signal standardizer in the left vertical compartment.
b. Set the VERT MODE to LEFT.
c. Set the signal standardizer Amplitude and Position controls for a centered, six-division
display. Set the Rep Rate for 100 kilohertz.
d. Set the time-base unit for a sweep rate of one microsecond/division and adjust the trigger
level for a stable display.
e. CHECK--For optimum square corner and flat top on the displayed pulse with aberrations not to
exceed +0.1 division with total peak-to-peak aberrations not to exceed 0.2 division.
f. ADJUST--R2409 (4), shown in Figure 8-20, for a flat pulse top and minimum aberrations in the
first one-microsecond area.
g. Set the time-base unit for a sweep rate of 0.5 microsecond/division and adjust the trigger
level for a stable display.
h. CHECK~—For a flat top on the first 500-nanosecond portion of the pulse within the limits in
step e.
i. ADJUST—R2509 (5) for a flat pulse top in the first 500-nanosecond area.
j. Set the signal standardizer Rep Rate to one megahertz and the time base for a sweep rate of
0.1 microsecond/division. Adjust the trigger level for a stable display.
k. CHECK--For a flat first 120-nanosecond area of the pulse top within the aberration limits
listed in step e.
t. ADJUST~—R2511 (7) and C2511 (8) for flatness and minimum aberrations of the first 120-nanosecond
area of the pulse top. R2511 adjusts tilt and C2511 adjusts for flatness.
m. Set the sweep rate ta 0.05 microsecond/division and adjust the trigger level for a stable display.
n. CHECK--For a flat first 30-nanosecond area of the pulse top within the limits fisted in step e.
o. ADJUST—R2411 (6) for flatness in the first 30-nanosecond area of the pulse top.
p. Set the sweep rate for 20 nanoseconds/division and adjust the trigger level for a stable display.
q. CHECK—For optimum leading corner and flat pulse top with minimum aberrations in the first
10-nanosecond area within the limits listed in step e.
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