A control system includes an electrical load control device responsive to radiant energy and a transmitter. The transmitter includes two sets of radiant energy generators connected to an electrical circuit such that polarity of the sets is reversed. A transmissive enclosure includes indented portions defining deflectors oriented obliquely with respect to a generator support surface. The transmitter is secured to a bracket for attachment to a backcover of the load control device. The control system may also include a master control generating an electrical control signal in response to an actuator or in response to a radiant energy signal. The control system is capable of limiting the master control to generate a signal only in response to the actuator. A power supply for the transmitter includes a filter network having a filter capacitor and resistor in series with a power supply capacitor and a diode in parallel with the resistor.