For the use of cables or infra-redremotecontrol system, in the receiver's direction and distance have greater restrictions.
对于使用电缆或红外线的遥控系统来说,在接收器的方向性和距离方面都有较大的限制。
3
NOTE An infra-redcontrol by itself is not considered one used for remote operation. However, it may be incorporated as part of a system such as a telecommunication, sound control or bus system.