APPA 506 - Voltage and dB Measurements; AC and DC Voltage Measurement; dB Measurement Procedure

506/506B
EN
Measuring AC and DC Voltage
Make dB measurement
This meter have true rms readings, which are accurate
for distorted sine waves and other waveforms (with no dc
o󰀨set) such as square waves, triangle waves, and staircase
waves.
The ranges of measuring voltage are 40mV, 400mV, 4V,
40V, 400V and 1000V. To select the mV range, turn the
rotary switch to mV position.
The meter is capable of displaying voltage as a dB value, either
relative to 1 milliwatt (dBm), a reference voltage of 1 volt (dB).
A dBm measurement must use a reference impedance (600Ω)
to calculate a dB value based on 1 milliwatt. A dB measurement
uses a 1 volt reference voltage to compare the present
measurement against. Dene as below :
For best accuracy when measuring the DCmV, touch the
probe tips together and read the DC o󰀨set. If necessary, you
can use the relative (Δ) mode to automatically subtract this
value.
AC Voltage DC Voltage
dBm = 20log
( )
Vrms
dBm = 20log
( )
Vrms
1V
6