If it is required to change the start frequency of the analysis, lift up the guide clip above
the paper drive sprocket wheel and pull the paper forward to a position where the pen is
2,5 mm (third octave) or 7,5 mm (octave) before the centre of the frequency marking-5
corresponding with the centre frequency of the third octave or octave band in which ana-
lysis is to commence. No further readjustment of the PAPER ADJUSTMENT, AUTO-
MATIC STOP or FILTER SHIFT SYNC. wheels is needed.
Note: To avoid disturbance from noise during filter shift, there must be a certain mini-
mum dwell time between filter steps at the low frequency end of the range. Suitable
time intervals occur when the following paper speeds are maintained.
Filter bands 2 Hz to 10Hz
Filter bands 10 Hz to 25 Hz
Filter bands above 25 Hz
Paper speed -c", 1 mm/s
Paper speed < 3 mm/s
Paper speed 5 10 mm/s
Correct choice of writing speed will normally require equally low paper speeds, so that
in practice there will be no disadvantage. See section 5.3.
22
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