Casella CEL CEL-269 - Manual (Page 5)

990020
C4963/2 CABLE
C4963/2 CABLE
LEVEL RECORDER
TAPE RECORDER
When L EQ (Equivalent Noise Level Measure-
ment) mode is selected the current L
eq
calculated by the microprocessor will be
displayed and updated every half second.
Press the RESET button to clear the L EQ
display for the next measurement.
8. Time-weighting Selection
Select F (fast response) when it is necessary to
follow the variation of noise levels.
Select S (slow response) when the general
sound levels are relatively constant.
Select I (impulse response) for more rapidly
varying noise when it is necessary to investi-
gate the impulsive components.
This setting has a fast rise time to capture the
level, with a slow decay that allows it to be
displayed for approximately 1.5 seconds.
9. Switch the instrument OFF (RESPONSE switch
to OFF) when not in use; remove batteries
when out of service for long periods.
USE WITH RECORDERS
Connection for tape recorders and graphic level
recorders is made via the same 3.5 mm 3-pole
coaxial socket in the bottom of the instrument, as
shown.
Connection between the sound level meter and
recorder is made via a C4963/2 (2 m) Cable
terminated with a BNC plug. The connections in
this cable provide a conditioned a.c output signal
proportional to indicated sound level, with 7.25 V
RMS full scale deflection.
When recordings are to be made, it is
recommened that the sound level meter be
calibrated as described above, and that a
calibration level be incorporated into the
recording. For more precise details refer to the
relevant recorder handbook.
Specification
Type:
Sound level meter according to ANSI S1.4 Type
2A, IEC 651 Type 2, and BS 5969 Type 2.
Impulse sound level meter according to IEC 651
Type 2I.
Integrating averaging sound level meter according
to IEC 804 and BS 6698.
Dynamic range:
70 dB.
Typical instrument frequency range:
(within +0.5 to -3 dB)
Better than 10 Hz to 25 kHz in all ranges.
Accuracy: (under reference conditions)
± 1 dB.
Lowest frequency for non-linear
distortion <1 dB:
5 Hz.