BRUEL & KJAER Mediator 2238, Руководство по обслуживанию, Страница: 19 / 34

Chapter 2 — Checking Procedure
Checking Procedure
2238 Mediator Integrating Sound Level Meter
Service Manual
BI 5043 –13
13
Table 2.1 The relation between the Display reading and the DC and AC Output
2.3.3 Frequency Weighting
Action:
●
Set the generator to 1000 Hz and adjust the output so that Type 2238 reads
128.0 dB
in SPL for Linear (LLFP) mode.
●
You must readjust the output to 128.0 dB at 1000 Hz when you change weighting
to A - Weighted (LAFP) and again when you change to C - Weighted (LCFP). To
change weightings, press
, then to
Weightings
and to select. Use to
navigate to the
Freq. Wgt.
line, and to the next desired weighting. Use to
OK
and to close and return to the active display.
Table 2.2 Linear (LLFP)
Table 2.3 A-Weighted (LAFP)
Input
dBµVRMS
SPL Reading
on
Display
DC Output
mV
Actual
Reading
AC Output
mV
Actual
Reading
approx. 126 REF. 130.0 4000 ± 50 1000 ± 50
Generator Freq.
Hz
dB SPL value on the
Display
Actual
Reading
Ref 1000 128.0 128.0
10
127.7
±
1.0
19950
126.0
±
1.0
Generator Freq.
Hz
dB SPL value
on the Display
Actual
Reading
Ref 1000 128.0 128.0
15.85 71.3 +1.0/ – 3.0
63.1
101.8
±
0.5
3981
129.0
±
0.4
19950 118.7 + 1.0/ – 3.0