Controls,  Connectors,  and  Indicators
RUNS  AFTER—Starts  the  B  sweep  immediately  after the  delay time 
selected  by the |<- OR  DELAY control.
The  Trigger  MODE  must  be  in  RUNS  AFTER  before  time  measure
ments can be selected when the Horizontal MODE is ALT or B.  A time 
measurement  will  be  canceled  if  the  Trigger  MODE  is  changed  from 
RUNS AFTER  while  in the ALT  or  B  Horizontal  MODE.
NORM—The  B sweep is triggered when an adequate trigger signal is 
received  after  the  delay  time  condition  has  been  met.  When there  is 
no  trigger signal,  there  is  no B  sweep trace.
TV LINE  FROM A SOURCE—Starts the B sweep  at the beginning of 
the video  signal  line received  after the  delay time  has been  met.
SLOPE polarity defaults to the A Trigger SLOPE.  This must match the 
composite  sync  polarity to  obtain  correct  triggering  on the  horizontal 
sync  pulse.
( 37)  SOURCE  (Up-Arrow  and  Down-Arrow)  Buttons  and  Indi
cators—Select  the  trigger  source  for  either  the  A  or  the  B  Trigger 
system  as  directed  by  the  A/B  SELECT  button.  Pressing  the 
Up-/Down-Arrow  SOURCE  buttons  selects  the  trigger source  (for A 
or  B trigger system)  as  shown by SOURCE lights.
VERT—Selects the  trigger signal from the  displayed waveforms.
The TRIGGER MODE and VERTICAL MODE switch settings determine 
the  trigger  signal  source  selection.  When  VERT  is  selected,  one  or 
more  of  the  SOURCE  lights  will  be  on  to  indicate  the  trigger  signal 
source.  See  Table  2-1  for VERT  Trigger SOURCE  selections.
CH  1—The  signal  applied  to  the  CH  1  OR  X  input  connector  Is  the 
source  of the trigger  signal.
CH 2—The signal applied to the CH 2 input connector is the source of 
the trigger  signal.
CH 3—The signal applied to the CH 3 input connector is the source of 
the trigger signal.
2245A  Operators
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