2-6
IM DL850E-01EN
Input Coupling (Coupling)
It is easier to measure the amplitude of an AC signal if you remove its DC component. On the other hand, there
are times when you want to measure the ground level or observe the entire signal, including both the DC and
AC components. In these kinds of situations, you can change the input coupling setting. By changing the setting,
you can choose how the vertical-axis (voltage-axis) control circuit is coupled to the input signal. You can set the
input coupling to one of the options listed below.
DC
The input signal is coupled directly to the attenuator of the vertical control circuit. Set the input coupling to DC
when you want to measure the entire signal, including both the DC and AC components.
AC (Only when measuring AC voltage)
The input signal is coupled to the attenuator of the vertical control circuit through a capacitor. Set the input
coupling to AC when you want to measure only the amplitude of the AC signal without the DC component.
GND
The input signal is coupled to the ground rather than to the attenuator of the vertical control circuit. Set the input
coupling to GND to check the ground level on the screen.
1 MΩ
1 MΩ
DC
AC
GND
Vertical
control
circuit
Vertical
control
circuit
Vertical
control
circuit
Input terminal
Input terminal
Input terminal
TC (Only when measuring temperature)
Set the coupling to TC when you are measuring temperature using the 701261 (UNIVERSAL), 701262
(UNIVERSAL (AAF)), 701265 (TEMP/HPV), or 720221 (16-CH TEMP/VOLT).
DC-RMS
With the 701267 (HV (with RMS)), the DC and AC components of the input signal are converted to RMS values
and displayed. An RMS conversion circuit is connected to the same vertical-control-circuit coupling arrangement
that is used when the coupling is set to DC.
AC-RMS
With the 701267 (HV (with RMS)), the AC components of the input signal are converted to RMS values and
displayed without the DC component. An RMS conversion circuit is connected to the same vertical-control-circuit
coupling arrangement that is used when the coupling is set to AC.
Vertical
control
circuit
Input terminal
1 MΩ
DC-RMS
RMS
conversion
circuit
AD
Input terminal
1 MΩ
AC-RMS
AD
Vertical
control
circuit
RMS
conversion
circuit
2 Vertical Axis