Controls,  Connectors,  and  Indicators
DC—Couples  dc  and  all  frequency  components  of the  input  signal to 
the vertical  attenuator when  the  DC  button  is  lit.
Turning on  DC coupling  turns  off AC  coupling.  With  DC  Coupling  se
lected,  a DC  symbol  (  )  is displayed to the right of the associated
VOLTS/DIV readout.  Input resistance  is  1  M il  to ground.
Refer to Figure 2-3  for location  of items  18  through  23.
18)  CH  1  OR  X  and  CH  2  Input  Connectors—Connect  signals  to  the 
inputs of Channel  1  and Channel 2  vertical  attenuators.
Input  connectors  are  BNC type with  an outer  contact  ring for recog
nizing  attenuation factors  of  coded  attenuator probes.  A signal con
nected to the CH  1  OR X input connector  produces the  horizontal de
flection  (X-Axis)  in the X-Y horizontal mode.  Any of the vertical signal 
channels  or ADD  can  provide  vertical  deflection  (Y-Axis)  for  an  X-Y 
display.
(19)  PROBE  ADJUST  Connector—Outputs  a  0.5  V  square-wave  signal
(at  about  1  kHz  into  a  1  M fl  load)  for  compensating  voltage  probes 
and  checking the vertical deflection  accuracy.
Figure  2-3.  Vertical  connectors  and  CH  3  and  CH 4 
controls  and  indicators.
2-6 2245A  Operators