Performance  Check  Procedure
e.  CHECK—that the sine-wave generator output frequency is between 17 
MHz and 23  MHz.
f.  Disconnect the test setup.
19.  Common-Mode  Rejection  Ratio
a.  Connect leveled sine-wave generator  (SG 503)  output to the CH  1  and 
CH  2 input connectors via a 50 Cl  precision  BNC coaxial  cable,  a 50 f 1 
BNC  termination,  and  a  BNC  dual-input  coupler.
b.  Set the leveled sine-wave generator output for an eight-division signal- 
display  amplitude  at  50 kHz.
c.  Set:
VERTICAL  MODE 
CH  2  VOLTS/DIV 
CH  2  INVERT 
SCOPE  BW
ADD  (CH  1  off) 
10 mV 
On 
Off
d.  Adjust  CH  1  or  CH 2  VAR VOLTS/DIV (as needed)  for smallest signal 
amplitude.
e.  Set the  leveled sine-wave output frequency to  50  MHz.
f.  Set the  VERTICAL MODE to  CH  1  (ADD  off).
g.  Set  the  leveled  sine-wave  output  amplitude  for  an  eight-division  dis
play.
h.  Set the  VERTICAL  MODE to ADD  (CH  1  off).
i.  CHECK—the  signal  is  less than  0.8  division  in amplitude.
j.  Disconnect the  test  setup.
2245A  Operators 7-23