Casella CEL CEL-393 - Manual (Page 50)

Answers must, however, be read out before the memory is reset to allow
any of the other memory modes to be selected. To prevent events
occuring during frequency analysis, this mode is disabled on selection
of the filter, and may be re-entered only by switching the unit OFF, and
then ON again with the filters switched out of circuit.
External Control
In order to operate the filter under the control of a CEL-160 Graphic
Recorder, the cable set type C4209 is required. The signal cable (C4187)
should be connected between the sound level meter's AC output socket
and the recorders preamplifier input connector.
The second control cable connects between the auxiliary sockets on the
CEL-393B and the CEL-160.
The recorder should be set to the Lin (Flat) frequency weighting, and
calibrated via the sound level meter in the usual manner for auxiliary AC
inputs. The required filter annotation should then be selected on the
1/3 Octave
dB
11.5
11.0
10.5
11.0
10.0
10.0
10.0
17.0
10.5
42.0
24.5
1/1 Octave
dB
14.0
12.5
18.0
Filter Freq.
Hz
3100
4000
5000
6300
8000
10000
12500
16000
20000
All Pass
(Lin)
A-weighting
Table 5 Typical self
noise (continued)
/46. 393 Handbook