BRUEL & KJAER Mediator 2238, Руководство по обслуживанию, Страница: 26 / 34

Chapter 2 — Checking Procedure
Checking Procedure
2238 Mediator Integrating Sound Level Meter
Service Manual
Brüel & Kjær
20
frequency. For the frequencies over 50 Hz, set the weighting to
1/3-octave/F
so the
readings are available faster.
Table 2.10 Center Frequencies in Hz
2.3.12 Initial Calibration
This procedure must be performed if the entire Type 2238 has been replaced as an
FRP or if the microphone has been replaced. It sets the initial values for the micro-
phone and allows comparison between the sensitivity as measured after the micro-
phone first left the factory and the condition of the microphone today. Not to be
confused with Initial Accredited Calibration, which is where a 2238 undergoes a full
calibration prior to delivery to the customer when the unit is first purchased.
●
Assure that batteries are new, or use a power supply during this procedure.
●
Place 2238 in LCFInst mode by setting
Bandwidth:
to
BB/F
and
Freq. Wtg.:
to
C
.
●
Connect the serial port on the PC to the serial port on Type 2238 using Cable
AO 1386 or AO 1442.
●
Use software “2238 Mediator Software”, Order Number VP 7767.
●
To start the program: press Windows
Start
and select
Run
. Enter the full path
plus filename
setup.exe <space>/i
(the i is case sensitive so type it in lower
case only). Click
OK
. If you attempt to run the program by simply double-clicking
on the program name, you will not get the option to do the initial calibration.
●
Follow the instructions in the dialog window.
Input
Freq.
Actual
Input
Freq.
Actual
Input
Freq.
Actual
Input
Freq.
Actual
Input
Freq.
Actual
20 80 315 1.25k 5k
25 100 400 1.6k 6.3k
31.5 125
500 2k 8k
40 160
630 2.5 10k
50 200 800 3.15k 12.5k
63 250 1k 4k