Срок на наличността:
Control broadcast sound of sound pressure in the region,
usually by resistance or pressure type transformer points to achieve;
There are three kinds of general volume controller.
One, the background music volume control, it is a two wire,
do not need to fire broadcasting places;
The volume of the two, with strong fire broadcast cut controller
(which with strong cut the volume of the controller according
to its strong cutting way three wire system and four wire system),
What is cut, when regional use will be the volume
control volume to very few, even in close,
when there is an urgent notice or fire Control room by issuing
an emergency control signal to the volume controller,
force the volume controller into the radio, and is not affected by the
volume controller The state of the influence, entered the state radio.
Third, choose the volume controller, as the name implies
the volume controller can control the volume of also can
choose different music at the same time,
it also Fire and don't need to cut two fire is strong,
and the selected volume controller can only use four wire system.