Tektronix 2230 Service Manual page 135

12. Check Common-Mode Rejection Ratio
a. Set:
BW LIMIT
CH 2 VOLTS/DIV
INVERT
b. Connect the leveled sine-wave generator output via
0
a 50 cable, a 50 Q termination, and a dual-input coupler
to the CH 1 OR X and the CH 2 OR Y input connectors.
c. Set the generator to produce a 50 MHz, 6-division
display.
d. Vertically center the display using the Channel 1
POSITION control. Then set the VERTICAL MODE switch
to CH 2 and vertically center the display using the Chan­
nel 2 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 con­
trol for minimum display amplitude.
1 . Set the VERTICAL MODE switch to CH 1.
m. Set the generator to produce a 50 MHz, 6-division
display.
n. Set the VERTICAL MODE switch to BOTH.
o. CHECK—Display amplitude is 0.6 division or less.
REV MAY 1987
Off (button out)
10 mV
On (button in)
Performance Check Procedure— 2230 Service
p. Disconnect the test equipment from the instrument.
13. Check Non Store and Store Channel Isolation
a. Set:
VERTICAL MODE
VOLTS/DIV (both)
VOLTS/DIV Variable
(both)
INVERT
Channel 1 AC-GND-DC
Channel 2 AC-GND-DC
A SEC/DIV
b. Connect the leveled sine-wave generator output via
Q
a 50 Q cable and a 50
input connector.
c. Set the generator to produce a 50 MHz, 5-division
display.
d. Set the VERTICAL MODE switch to CH 2.
e. CHECK— Display amplitude is 0.05 division or less.
f. Move the cable from the CH 1 OR X input connector
to the CH 2 OR Y input connector.
g. Set:
VERTICAL MODE
Channel 1 AC-GND-DC
Channel 2 AC-GND-DC
h. CHECK— Display amplitude is 0.05 division or less.
i. Set:
CH 2 VOLTS/DIV
STORE/NON STORE
SAVE/CONTINUE
j. CHECK— Display amplitude is 0.1 division or less.
k. Move the cable from the CH 2 OR Y input connector
to the CH 1 OR X input connector.
CH 1
0.1 V
CAL detent
Off (button out)
AC
GND
ft
0.1 s
termination to the CH 1 OR X
CH 1
GND
AC
50 mV
STORE (button in)
CONTINUE (button out)
4-9