Hitachi V-355, Operation Manual

Page: 22 / 54

7.
The first things to do are as follows.
o
Bring the brightness and FOCUS at optimum positions
for easy read out.
o
Display the waveform as large as possible to minimize
the read error.
o
Check the capacity correction when using a probe.
(Refer to Paragraph ( I ) "When using a probe" of Sec­
tion 6. "Method for connecting signals" for the method
for correcting capacity.)
(1)
DC voltage measurement
Set input coupling to GND and decide the zero level prop­
erly.
Set VOLTS/DIV appropriately and set AC-GND-DC to
DC. Since the base line shifts here by the amount of
DC voltage , the DC voltage of the signal can be obtained
by multiplying the shift width by the indicated value of
VOLTS/DIV. When VOLTS/DIV is 50 mV/DIV, then
50 mV/div x4 .2
=
2 1 0 mV (However, if the probe AT-
1 0 AJ 1 .5 is in use , the true value of the signal becomes
1 0 times the value , or
. 50 mV/div x 4.2 x 1 0
=
2.I V.)
DC voltage (after shifting)
Zero level (reference line)
(2) AC voltage measurement
The same as paragraph
7
( I ), "DC voltage measurement",
but here those is no need of matching the zero level with
the scale line. Move the zero level at will to a position easy
to observe .
In the drawing as follows, VOLTS/DIV is I V/DIV, I V/
div
x
5
=
5 Vp-p (50 Vp-p at time using the probe AT-
1 0 AK 1 .5). When magnifying and observing a small­
amplitude signal, superimposing on a high DC voltage,
set input coupling to AC . The DC voltage is cut off and
AC voltage can be observed by increasing sensitivity.
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