5-7
IM 701730-01E
Vertical and Horizontal Axes
5
5.4 Setting the Input Coupling
Explanation
Selecting the Input Coupling
You can select the method of coupling the input signal to the vertical control circuit from
the following.
AC1 M
Ω
: Acquires and displays only the AC component of the input signal.
DC1 M
Ω
: Acquires and displays all the components (DC and AC) of the input signal (1
M
Ω
input).
DC50
Ω
: Acquires and displays all the components (DC and AC) of the input signal (50
Ω
input).
GND:
Checks the ground level.
Input Coupling and Frequency Characteristics
The frequency characteristics when AC1M
Ω
, DC50
Ω
, and DC1M
Ω
is selected are
shown below.
Note that when AC1M
Ω
is selected, low frequency signals or signal components are not
acquired (as shown in the figure below).
0 dB
–3 dB
500 MHz
400 MHz
Attenuation
0 dB
–3 dB
400 MHz
Attenuation
10 Hz or less when using the 1:1 probe
1 Hz or less when using the 10:1 probe
Input frequency
Input frequency
When AC1 M
Ω
is selected
When DC50
Ω
or DC1 M
Ω
is selected
When DC50
Ω
is selected
When DC1 M
Ω
is selected
CAUTION
The maximum input voltage for 1-M
Ω
input when the frequency is 1 kHz or less
is 400 V (DC + ACpeak) or 5 Vrms or 10 peak for 50
Ω
input. Applying a
voltage exceeding either of the two values can damage the input section. If the
frequency is above 1 kHz, damage may occur even when the voltage is below
this value.