Jess UEAB 2006 Television Tuner

Jess UEAB 2006 Section of the Tuner VHF Tuner UHF Tuner Automatic Fine Tuning AFT Remote control

Jess UEAB 2006 TV Tuner Broadcast Tuners Have dedicated Microprocessor used to select and program channels

Jess UEAB 2006 Typical TV Tuner Block Diagram

Jess UEAB 2006 Distinct section in Tuner section RF Amp RF AmpMixerOscillator

Jess UEAB 2006 Oscillator Function To increase the signal strength so that the signal to noise ratio is increased To isolate local oscillator from the antenna

Jess UEAB 2006 TV Channel Tuning Characteristics Be able to select VHF UHF Cable channels total of 135 Channels No system alignment No mechanical switching Remote control capability Tuning system should be reliable and low cost In touch tuning channel are change by touch Permits operator to change channel sequentially Employ microprocessors Manual Programming PLL

Jess UEAB 2006 PLL

PLL Cont.

Jess UEAB 2006 Microprocessor

Microcomputer Tuner

Jess UEAB 2006 Use of Tuner Microcomputer Scan the digital keyboard for contact closures Control the operation of the LED channel display through LED drivers Provide positive voltage supply switching Control the PLL frequency synthesizer

Jess UEAB 2006 Tuner RF Amplifier Improves signal to noise ratio to the receiver Provides amplification Provides selectivity Isolates the oscillator from the receiving antenna

Jess UEAB 2006 RF Amplification Diagram

Jess UEAB 2006