Hitachi V-209, Operation Manual

Page: 24 / 47

Connection of earth lead wire
20
(a)
A
good example
(b)
A
bad example
For better measurement. it is required to use an earth
attachment available at option.
Multiply the reading of VOLTS DIY by 10.
For example. if the VOLTS/DIY ts SOmV/DIV. then
read the wavefonn as
SOmV/DIV
x
10
=
SOOmV/DIV
o To avoid measurement error, put the probe in the follow­
ing correction state and check it before measurement
without fail.
Connect the tip of the probe to the output tenninal
CAL O.SV of I kHz calibration square wave voltage.
When this correction capacity value is at optimum, the
wavefonn takes the shape as shown in Fig. (a) as follows.
If the wavefonn is as shown in Fig. (b) or Fig. (c),
rotate the semiftxed adjusting screw on the matching
box of the probe by using a screwdriver until the opti­
mum state is obtained.
L
Capacitance correction trimmer
JliUlJ1
MJUl MM
(a)
Optimum
(b) Capacity too
small
(2) At time of direct connection
(c) Capacity too
large
When connecting a signal directly to the oscilloscope not
usmg the attached probe
AT
-10 AK 1.5 (I O· 1
)
, pay atten­
tion to the following points in order to minimize the mea­
surement error.
o
When perfonning observation using a bare lead wire, no
trouble occurs on the circuit to be measured at low
impedance and high level.
However. note that, in most cases. measurement error
may be caused by static stray coupling with other circuit
and power line.
This measurement error cannot be ignored even in low
frequency region.