g) Attenuation measuring in dBm
The multimeter VC-2020 enables absolute "dB" measuring in circuits with an impedance of 600 Ohm.
Measuring takes place in the „V~" range. 0dB = 1mW.
Proceed as follows for the measurement:
- Select the measuring range "10V"
- Connect the black measuring line with the COM socket (8) and the red
measuring line with the V-mA socket (9).
- Now perform null balancing.
- Now connect the two measuring prods to the object to be measured
(generator, circuit etc.).
- Read off the measuring value on the scale "dB".
The dB scale corresponds to the 10V measuring range.
If another measuring range is selected, a correction factor must be considered in the calculation.
AC-V range
Correction factor
Display range (dB)
If signals with a direct voltage ratio are to be measured, a capacity of >0.1nF must be switched in series
to the measuring leads (decoupling).
Cleaning and maintenance
General
To ensure the accuracy of the multimeter over an extended period of time, it should be calibrated once a
year.
Information on changing the battery and fuse appears below.
Periodically check the technical safety of the instrument and measuring lines, e.g.
check for damage to the housing or squeezing etc.
Never operate the measurement device when it is open.
!RISK OF FATAL INJURY!
30
on the rotary switch.
2.5 V
10 V
-12dB
0dB
-22 ~ +10
-10 ~ +22
50 V
250 V
+14dB
+28dB
+4 ~ +24
+18 ~ +50
5A
500 V
+34dB
+24 ~ +56