Hitachi V-355, Руководство по эксплуатации

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Connection of earth lead wire
(a)
A
good example
(3) A
bad example
o
Multiply the reading of VOLTS/DIV by I O.
For example, if the VOLTS/DIV is SOmV/DIV, then
read the waveform as
S OmV/div
x
1 0
=
SOOmV/div
o
To avoid measureme nt 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 CAL O.SV tip of
l kHz calibration square wave .
When this correction capacity value is at optimum the
waveform takes the shape as shown in Fig. (a).
If the waveform is as shown in Fig. (b) or Fig. (c),
rotate the trimmer on the matching box of the probe by
using a screwdriver until the optimum state is obtained.
L
Capacitance correction trimmer
(a} Optimum (b) Capacity too
small
(2) At t
iip
e of direct connection
(c) Capacity too
large
When connecting a signal directly to the oscilloscope not
using the attached probe AT- 1 0 AK1 .5 ( 1 0 : 1 ), pay atten­
tion to the following points in order to minimize the mea­
sureme nt error.
o
When performing observation using a bare lead wire, no
trouble occurs of the circuit to be measured is of 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.
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