BRUEL & KJAER 1617 - Page 28

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I I
I Level Recorder 2307 I
I I
I
J
710361
Fig. 3. 9. Instrumentation using Type 2307 to plot spectrograms
with fixed averaging time
RECTIFIER RESPONSE As applicable
LOWER LIMITING
FREQUENCY Depends upon the starting frequency
WRITING SPEED Depends upon the starting frequency ; see sections
4.2 and 4 .3 and the Level Recorder Instruction
Manual
PAPER DRIVE FUNCTION
PAPER SPEED
DRIVE SHAFT II SPEED
PEN DRIVE
INPUT POTENTIOMETER
INPUT
ATIENUATOR
" Automatic Stop F"
" 10 mm/ sec" , note that synchronization pulses
are only available for filter switching when the
sliding switch is in the " mm / sec" position ; see
also sections 4 .2 and 4 .3 .
Immaterial
" On"
" 0"
" 60 dB"
5. Calibrate the Level Recorder as follows : turn up the Level Recorder INPUT POTEN-
TIOMETER
and INPUT ATIENUATOR to position the pen on the chart paper 4 dB
above a
thick graduation line (dependent upon Potentiometer in use). The pen move-
ment is now calibrated to follow the meter needle accurately, and one dB on the
paper is equivalent to one dB on the meter scale.
6. Release the 50 mV REFERENCE VOLTAGE.
7 . The paper
transport is synchronized with filter switching as follows .
8 . Set the Band Pass Filter RANGE switch to the range to be measured .
9. Set
the Level Recorder controls:
PEN DRIVE
"Off"
PAPER DRIVE
"Start", and let the paper run until it stops itself
1 O. Push the pen by hand up to the top of the paper.
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