A And B Frequency Weighting, Sw2; Trip Level, Sw3; Warning Level, Sw4 - Castle group Electronic Orange GA904 Operating Manual

A and B Frequency Weighting, SW2

This is a two way switch which selects the required frequency weighting. The
switch must be switched right for "A" weighting and left for "B" weighting.
Figure 5.1 shows the "A" and "B" frequency weighting characteristics.

Trip Level, SW3

This switch is used to set the trip level from 75dB to 112.5dB in 2.5dB
increments.

Warning Level, SW4

This switch is a four way slide switch selects when the warning beacon will
switch on. The level is relative to the trip level and may give a warning –3, -6, -
9, or –12dB down from the trip level.
The following tables show the switch position against trip level, and warning
levels.
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