Tektronix 2215A, Instruction Manual

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Adjustment Procedure—2215A Service
g. CHECK— Display amplitude is 0.05 division or less.
h. Disconnect the test equipment from the instrument.
16. Check Com m on-Mode Rejection Ratio
a. Set:
VOLTS/DIV (both) 10 mV
INVERT On (button in)
Channel 2 Input Coupling DC
b. Connect the leveled sine-wave generator output via a
50-fi cable, a 50-SJ termination, and a dual-input coupler to
the CH 1 OR X and CH 2 OR Y input connectors.
c. Set the generator to produce a 25-MHz, 6-division
display.
d. Vertically center the display using the Channel 2 POSI­
TION control. Then set the VERTICAL MODE switch to
CH 1 and vertically center the display using the Channel 1
POSITION control.
e. Set the VERTICAL MODE switches to BOTH and
ADD.
f. CHECK— Display amplitude is 0.6 division or less.
g. If the check in part f meets the requirement, skip to
part p. If it does not, continue with part h.
h. Set the VERTICAL MODE switch to CH 1.
i. Set the generator to produce a 50-kHz, 6-division
display.
j. Set the VERTICAL MODE switch to BOTH.
k. Adjust the CH 1 or CH 2 VOLTS/DIV Variable control
for minimum display amplitude.
I. Set the VERTICAL MODE switch to CH 1.
m. Set the generator to produce a 25-MHz, 6-division
display.
n. Set the VERTICAL MODE switch to BOTH.
o. CHECK— Display amplitude is 0.6 division or less.
p. Disconnect the test equipment from the instrument.
17. Check Input G ate Current
a. Set:
VERTICAL MODE CH 1
VOLTS/DIV (both) 2 mV
VOLTS/DIV Variable (both) CAL detent
Input Coupling (both) GND
b. Position the trace on the center horizontal graticule
line using the Channel 1 POSITION control.
c. CHECK— For 0.1 division or less trace shift while
alternating the Channel 1 Input Coupling switch between the
AC and GND positions.
d. Set the VERTICAL MODE switch to CH 2.
e. Repeat parts b and c using the Channel 2 controls.
NOTE
To continue with the Adjustm ent Procedure, remove
the instrum ent cabinet and allow a 20-minute time pe­
riod to elapse before continuing with the Adjustm ent
Procedure. See the ‘Cabinet’ removal instructions lo­
cated in the “Maintenance" section o f the manual.
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