SONIC Radio Transmitter RT-IOCTL Operating Manual ‘Thank you for purchasing this product. Please read the instruction manual thoroughly to assure its safe and proper use. The RT-IOCTL Radio Transmitter is designed to fit into select Sonic light meters and transmit trigger signals © PocketWizard® receivers and transceivers as well as electronic flashes with PocketWizard® receivers built-in. ‘When installed, it enables one person working alone to measure flash output without the need of 4 sync cord.