BRUEL & KJAER 2209 - Use with Other Instruments; Level Recorder; Graphical Recording from the AC OUTPUT

7. USE WITH OTHER INSTRUMENTS
7.1. LEVEL RECORDER
A graphical recording
of sound or vibration levels measured with the
2209 may be made with the level recorder Type 2305 or 2307. Recordings
may
be taken from either the AC or DC OUTPUT of the 2209 as required.
7.1.1.
Graphical Recording from the AC OUTPUT
For the recording of varying, but non-impulsive, phenomena the AC
OUTPUT is preferred since this will give the best linearity over the greatest
dynamic
range. Recording from the AC OUTPUT is possible. in all positions
of the METER SWITCH.
In
positions "Peak Hold", "Imp. Hold", "Imp.", "Fast" and "Slow"
0.5 V RMS (corresponding to FSD) is available from the AC OUTPUT,
allowing
a 25 dB potentiometer range to be used in the level recorder.
In position "Batt. (Rec.") 5 V RMS is available and hence a 50 dB poten-
tiometer range may be used in the level recorder. In this mode the meter
scale indicates the condition of the batteries only, the signal level must
therefore
be read from the recording.
Fig.7.1
is an example of a recording made from the AC OUTPUT of the
2209.
- - ~ - - ~= • - ·
2307
AC
2209
172081
Fig. 7. 1. Recording of traffic noise
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