Magnified Sweep Gain; Magnifier Registration; Sweep Length; Variable Time/Div Range - Tektronix 7B51 Instruction Manual

e. CHECK-Timing accuracy is within 5% over any two
division interval with in the center eigh t divisions.
f. INTERACTION : Check steps 11 and 17.
11. Check/Adjust Magnifier Registration (R795)
a. Set the time-mark generator for 5 ms markers.
b. Position the middle marker to the center vertical line
(there are three markers o n the total magnified sweep) with
the horizon tal POSITION control. See Fig. 5-3A.
c. Set the MAGN IFIER to X1.
d. CHECK- Middle marker remains at the center vertical
line. See Fig. 5-3B.
1\
\
Fig. 5-3 . Tvpical CR T di$pl ev showing correct magnifi er
registration. (AI MAGNIFIER H t to X 10, (6) MAGNI FIER set to
Xl .
®I
Performance Check /Calibration-Type 7851
e. ADJUST - R795. Mag Regis, to position the middle
marker to the center vertical line .
f . Alternately switch the MAGN IF IER between Xl and
X10 and repeat steps b through e until no shift occurs when
switching.
12_ Check Sweep length
a. Set th e time-mark generator for 1 ms and .1 ms
markers. Reset the MAGNIF IER to Xl. Set the TR IGGER ·
ING MODE to AUTO.
b. Move the eleventh 1 ms marker to the center vertical
line with the horizontal POSITION control (see Fig. 5-4).
c. CHECK- Sweep length must be between 10 and 13
divisions.
13. Check Variab le Time/ Div
a. Reset the Type 7B51 Tl ME/DI V to 2 ms. Set the
time-mark generator for 10 ms markers.
b. Press and release the VARIABLE TIME/ DIV knob
and turn fu lly counterclockwise.
c. CHECK- CRT display for two-division maximum
spacing between markers (indicates adequate range for
continuously variable sweep rate between the calibrated
steps; see Fig. 5-5) . Return the VAR IABLE TI ME/ DI V to
the CAL IN position.
" -
"-
..
Fig . 5-4. Tvpical CRT di$plev when checking sweep length.
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