GMC-I Gossen-Metrawatt GmbH
19
GB
8.3
Alternating Voltage Level Measurement (dB)
The voltage level measurement is
used for determining the overall
damping or gain of a transmission
system (shown here as a two-port
network).
Voltage level [dB]
with V
1
= V
REF
(reference level rEF
vALUE
)
result > 1: gain; result < 1: damping
➭
Set the rotary switch to V
.
➭
Briefly press the multifunction key
ESC|FUNC
.
The level measurement function is now active. The mea-
surement value is calculated from the effective value of the
alternating voltage component dependent upon the mea-
suring range (300 mV ... 600 V), and is displayed. The
default setting for the reference level is 0 dB = 0.775 V
(1 mW at 600
Ω
) and appears in the left hand sub-display.
This value can be changed in the Setup menu:
SEt
↵
V
rEF
vALUE
↵
V
unit dB
↵
XXX.XXX V/dB
VU
↵
.
Note!
☞
No matching resistors have been installed into the
instrument. It takes measurements with a high input
resistance of 5 M
Ω
. Input resistance for voltage mea-
surement is listed under technical data. In order to
perform correct measurements at non-terminated
devices under test, a matching resistor must be con-
nected to the terminals. Observe power dissipation at
the matching resistor!
600V
V
F
°
C
U
N
= max. 1 kV
Voltage Measurement with
the KS30 Measuring Adapter
V
1
V
2
20
V
2
V
1
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log
⋅
=