CIRCUIT DESCRIPTIONS 32� TUNING SYSTEM OVERVIEW
The tuning system of CableCARDTM models have four essential parts: analog tuner, digital tuner, outer band tuner, and cable card slot.
Digital Tuner Digital Cable (QAM) and ATSC over-the-air.
Cable Card Slot Provides access to scrambled (encrypted) channels.
Outer Band Tuner Digital Cable Data Stream.
Cable Input Accepts both digital and analog cable.
Analog Tuner Analog cable and NTSC over-the-air.
Antenna Input Accepts both digital and analog overthe-air signals. Signal Splitter
Analog Tuner The analog tuner is a standard NTSC tuner. It tunes analog signals from off-the-air (OTA) broadcasts and analog cable signals. Digital Tuner The ATSC tunes digital OTA signals (8-VSB) and digital cable signals (QAM). It supports both QAM64 and QAM256 digital cable standards. Outer Band Tuner This tuner translates data from digital signals. Mainly used for communications between a cable card and the cable company. CableCARDTM Slot A cable card on a Digital Cable Ready (DCR) television decrypts encoded signals from digital cable allowing cable companies to protect content on certain channels. Please refer to our cable card training for more information. For more information refer to the Cablecard section a the end of this manual. TROUBLESHOOTING No Analog TV (Cable or OTA) Problem: Snow on all analog cable and OTA channels. Occasionally a memory card error appears on the screen. Resolution: Check the analog tuner on the jackpack PCB. Check circuitry and connections, replace the PCB if necessary. Directview LCD Training
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Circuit Descriptions