BRUEL & KJAER 2204 - Octave Filter Set; Calibration Checks

The Octave Filter Set.
A sketch of the Octave Filter Set is given in Fig. 4.2.
ctave
Selection
Weighting
Potentiometers
-163720
Fig. 4.2. The Octave Filter Set Type 1613.
IN and OUT.
These sockets are for connection to the Sound Level Meter external filter
sockets via
the Connection Bar JP 0400 or to other equipment via cables
AO 0034 or AO 0035. These sockets, like those on the Sound Level Meter take
B & K coaxial plugs JP 0006.
OCTAVE SELECTION.
This knob is used for selecting the required octave filter. The numbers
indicate pass-band centre frequency.
WEIGHTING POTENTIOMETERS.
These potentiometers are screwdriver operated and are used to give different
attenuation in each pass-band when the WEIGHTING SWITCH is in position
"On".
WEIGHTING SWITCH.
\Vhen this is set to "Off" the weighting potentiometers are out of action.
Calibration Cheek~.
Calibration checks are carried out now and then in order to make sure that
the instrument is working properly. Such checks are necessary when the
apparatus has been out of use for a long time, or when ambient conditions
have changed considerably. First check the condition of the batteries as
follows:-
Pull out KNOB 1 and set to position "Batt.". The meter pointer should
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