User Manual

32 GMC-I Gossen-Metrawatt GmbH
V/Hz, Ω, Temperature, and A/Hz Measurements
Alternating Voltage Level Measurement (dB)
Voltage level measurement is used in order
to ascertain overall attenuation or boosting
of a transmission system (shown here as a
4-pole setup).
Voltage level [dB]
where U
1
= U
REF
(reference level)
Result > 1: boosting
Result < 1: attenuation
Manually select the measuring range for the voltage amplitude.
When the instrument is switched to dB measurement, the pre-
viously selected voltage measuring range remains active.
Repeatedly press the FUNC | ENTER multifunction key until unit
of measure dB appears at the display.
Lowest measurable frequencies and maximum permissible
voltages are included in chapter 8, “Technical Data”.
The level measurement function is now activated. The measured
value is calculated based upon the RMS value of the alternating
voltage component relative to the measuring range (600 mV
1000 V), and displayed.
The default setting for th reference level is 0 dB = 0,775 V (1 mW
to 600 Ω). This value can be adjusted in the „SET “ menu (see also
chapter 6.4):
1nFo
... SET rAtE ... dbrEF
0 ..001 ... 99 V

Note
No terminal resistors have been integrated into the device. It
performs measurement with a high input impedance of
9MΩ.
Input impedance for voltage measurement is listed under
technical data.
In order to be able to perform correct measurement at non-
terminated devices under test, the terminating resistor must
be connected to the terminals. Be sure to take power loss at
the terminating resistor into consideration!
U
1
U
2
20
U
2
U
1
-------log
=
MEASURE
SETUP
FUNC
ENTER
FUNC
ENTER
FUNC
ENTER