Tektronix 2445, Instruction Manual

Page: 107 / 351

Performance Check— 2445 Service
HORIZONTAL
Equipment Required (see Table 4-1)
Leveled Sine-Wave Generator (Item 2) Time-Mark Generator (Item 5)
Calibration Generator (Item 3)
Precision 50 fi BNC Cable (Item 8)
Initial Control Settings.
Control settings not listed do not affect the procedure.
b. Adjust the TRIGGER LEVEL control as necessary for
a stable signal display.
Set:
VERTICAL MODE
CH 1 On (button in)
CH 2, CH 3, CH 4,
ADD, and INVERT
Off (buttons out)
CHOP/ALT ALT (button out)
20 MHz BW LIMIT Off (button out)
VOLTS/DIV
CH 1 0.5 V
CH 1 VAR In detent
CH 3 and CH 4 0.1 V (buttons out)
Input Coupling
CH 1 50 0 DC
A and B SEC/DIV 200 ns (knobs locked)
A and B SEC/DIV VAR In detent
X I0 MAG
Off (button out)
AV and At Off (press and release
until associated readout
is off)
TRACKING Off (button out)
TRACE SEP Fully CW
TRIGGER
HOLDOFF B ENDS A
LEVEL Midrange
SLOPE + (plus)
MODE AUTO LVL
SOURCE
VERT
COUPLING DC
c. Pull the B SEC/DIV knob out and set the B TRIGGER
MODE to RUN AFT DLY.
d. Set the AREF OR DLY control for a DLY readout of
approx 1000 ns.
e. VERIFY— An intensified zone appears on the dis­
played signal near graticule center.
f. Rotate the AREF OR DLY POS control to center the
intensified zone on one of the time markers near graticule
center.
g. Set the B SEC/DIV control to 50 ns (knob out).
h. Rotate the TRACE SEP control CCW to separate the
the A and B sweep displays.
i. CHECK—The B sweep is displayed with the A sweep.
j. Push the B SEC/DIV knob in.
k. CHECK— Only the B sweep is displayed.
2. Check A and B Timing, A Cursor Accuracies,
and A Cursor Range.
1. Check Horizontal Display Modes (A, A INTEN,
ALT, and B).
a. Use a 50 Q BNC cable to connect 200 ns time mark­
ers from the Time-Mark Generator to the CH 1 OR X input
connector.
a. Set:
A and B SEC/DIV
TRACE SEP
At
5 ns (knobs locked)
Fully CW
On (press and release
for At display)