Tektronix 442, Инструкция по эксплуатации

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Calibration Procedure—442 Service
Adjustment Procedure
1
FRONT
PANEL
SWEEP TIM IN G
(H IG H SPEED)
R2Q62 / R2321
X-Y G AIN / X10 GAIN
R2051
____ X-Y CENTERING 2374^77
Figure 4-12. Horizontal adjustment locations on A12 Horizontal
board and A l l Trigger Switch board.
3. Magnifier Registration
a. Set the time-mark generator for 5 millisecond time
markers.
b. Set MAGNIFIER to XI (button out).
g. INTERACTION—Between XI and X10MAGNIFIER
settings. Repeat adjustment of R2321 and R2330 and re­
set Horizontal POSITION control until there is no change
in time marker position when switching MAGNIFIER from
XI to X I0.
4. High Speed Sweep Timing
a. Set:
MAGNIFIER XI
b. Set SEC/DIVto.5 yuandsetthetime-markgenerator
for .5 microsecond time markers. Set POSITION and
INTENSITY controls as required.
c. ADJUST—High Speed Sweep Timing (C2235, see
Figure 4-12) for one time marker per graticule division
over the center 8 graticule divisions (use a low-
capacitance alignment tool).
d. Disconnect the time-mark generator signal fromthe
442.
5. X-Axis Centering (X-Y Centering)
a. Set:
SOURCE
CPLG
SEC/DIV
VERT MODE
INTENSITY CH 1/CH 2
AC
.1 m
CH 2
For visible trace
b. Set the Horizontal POSITION control so the sweep
starts at the extreme left graticule line. Set SOURCEto X-Y
and reduce INTENSITY setting so the displayed dot is
visible but not excessively bright.
c. Set the Horizontal POSITION control to align the c- ADJUST X-Y Centering (R2051, see Figure 4-12)
center time marker with the center vertical graticule line. t0 Pos^ ion the dot to the center vertical graticule line.
d. Set MAGNIFIER to X10 (button in) and use the
Horizontal POSITION control to move the closest time 6. X-Axis Gain fX-Y Gain)
marker to the center vertical graticule line (set INTENSITY ge{.
as required for visible time markers).
VOLTS/DIV (both) 10 m
AC-GND-DC (CH 1) AC
e. Set MAGNIFIER to XI (button out). AC-GND-DC (CH 2) GND
f. ADJUST—Mgf Rgtr (R2330, see Figure 4-11) so the
center time marker aligns with the center vertical graticule
line.
b. Connect a 1 kHz, 50 mV amplitude calibrator signal
through a 50 O bnc cable to the Channel 1 input connec­
tor.
4-24
REV A MAY 1980