General Tools and Instruments DSM8925 - Manual (Page 10)

The meter can display its results more quickly
because it does not have to first determine
which range to use.
To exit Autoranging Mode and enter
Manual Ranging mode, briefly press the RNG
button on the front panel. Note that when you
press the button, the text MANU replaces
AUTO on the left side of the display. Also note
that the Range Baseline above the left end of
the bar graph no longer changes in response
to louder or softer sounds, as in did in
Autoranging mode.
When the RNG button is pressed, the meter
randomly chooses one of the four ranges.
Accordingly, the first Range Baseline number
displayed could be 40, 60, 80 or 100. For the
highest display resolution, the low end of the
range you choose should be just below the
quietest sound you expect to hear. For
example, if your target normally produces
sound levels between 85 and 105 dB, you
should manually choose the 80 to 110 dB
range.
To manually select a specific measurement
range, briefly press the RNG button as many
times as necessary until its Range Baseline
number appears above the left end of the
analog bar graph. Each press of the RNG
button advances the Range Baseline number
by 20 dB; after 100, it returns to 40.
Note that in Manual Ranging mode, whenever
a sound level is outside the chosen range the
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