CTK50-D is a desktop UHF transmitter base unit for Wisycom intercom systems. The system comprises CST50-D UHF transmitter module and a PSP910 mains power supply, forming a portable minirack base suitable for fixed installations. It operates in the 400–550 MHz UHF band with 300 mW RF output and supports 16 switchable preset frequencies. The compact desk-mounted unit enables modular, scalable intercom configurations.