The CTV1M is the premiere Single Channel Digital Modulator on the market. This advanced unit is a 100% Digital Modulator with PLL Audio, Video and Adjustable Gain. The Modulator also features on-screen programming of the channel selection and gain level. This combines with a single-line Caller-ID input to distribute not only your video source but your Caller-ID information as well. FEATURES: 100% Digital ModulationPLL Locked Audio, Video and Adjustable Gain. Digital Adjustable Gain Control. Single-Line Caller ID built-in. Caller ID in formation overlays on the video source when a call comes in. On-screen programming of the channel selection and Gain level. Memory retained during power outages. Rugged aluminum enclosure. Includes wall transformer, 1 video cable, 1 audio cable and 1 RJ11 telephone cable.