General Tools and Instruments DSM8925 - Manual (Page 11)

digital display will show the letters LO or HI.
If this happens often, consider switching back
to Autoranging mode.
To exit Manual Ranging mode and return to
Autoranging Mode, press and hold the RNG
button until the text AUTO replaces MANU on
the left side of the display.
TIME AND FREQUENCY
WEIGHTING OPTIONS
You can choose Fast or Slow response time
and “A” or “C” frequency weighting to suit
different applications.
By default, when the meter is powered on it
begins operating with fast time weighting
(a fast integration time constant) and “A”
frequency weighting. Fast time weighting,
with a response time of 200 milliseconds,
simulates the response time of the human ear
and is better for measuring the volume of
singular events. Slow weighting, with a
response time of 500 ms, is a better choice
for measuring the average sound level that an
ongoing process (such as machine vibration)
produces over time.
To switch the meter’s response time from
fast to slow, press the F/S button. The word
on the right side of top line of the display will
change from FAST to SLOW. To return to fast
time weighting, press the F/S button again.
As mentioned earlier, when the DSM8925 is
powered on it begins operating with “A”
frequency weighting. The shape of the “A”
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