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

Calibration-7623AIR7623A 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. Set the VERT MODE to LEFT.
b. Set the signal standardizer Amplitude acd Position controls for a centered, six-division
display. Set the Rep Rate for 100 kilohertz.
c. Set the time-base unit for a sweeo rate
u i
ons microsecond/division and adjust the trigger
level for a stable display.
d. CHECK-For optimum square corner and flat top on the displayed pulse with aberrations not to
exceed fO.l division with total peak-to-peak aberrations not to exceed 0.2 division.
e. ADJUST-R2409 (4), shown in Figure 8-20, for a flat pulse top and minimum aberrations in the
first one-microsecond area.
f. Set the time-base unit for a sweep rate of 0.5 microsecond/division and adjust the trigger
level for a stable display.
g. CHECK-For a flat top on the first 500-nanosecond portion of the pulse within the limits in
step d.
h. ADJUST-R2509 (5) for a flat pulse top in the first 500-nanosecond area.
i. 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.
j. CHECK-For a flat first 120-nanosecond area of the pulse top within the aberration limits
listed in step d.
k. ADJUST-R2511 (7) and C2511 (8) for flatness and minimum aberrations of the first 120-nano-
second area of the pulse top. R2511 adjusts tilt and C2511 adjusts for flatness.
I. Set the sweep rate to 0.05 microsecond/division and adjust the trigger level for a stable display.
m. CHECK-For a flat first 30-nanosecond area of the pulse top within the limits listed in step d.
n. ADJUST-R2411 (6) for flatness in the first 30-nanosecond area of the pulse top.
o. Set the sweep rate for 20 nanoseconds/division and adjust the trigger level for a stable displav.
p. CHECK-For optimum leading corner and flat pulse top with minimum aberrations in the first
10-nanosecond area within the limits listed in step d.
REV. B, APR. 1978