BUSH 15TFT
Service Manual

1. INTRODUCTION
TFT TV is a progressive scan flicker free colour television with PC input, driving a XGA panel with 4:3 aspect ratio. The chassis is capable of operation in PAL, SECAM, NTSC (playback) colour standards and multiple transmission standards as B/G, D/K, I/I�, and L/L´. Sound system output is supplying 2x2W (10%THD) for left and right outputs of 8Ω speakers. The chassis is equipped with one full SCART, one front-AV, one SVHS, one D-Sub 15 (PC) input and one line out (left and right) and one HP outputs.

2. TUNER
The hardware and software of the TV is suitable for tuners, supplied by different companies, which are selected from the Service Menu. These tuners can be combined VHF, UHF tuners suitable for CCIR systems B/G, H, L, L´, I/I´, and D/K. The tuning is available through the digitally controlled I 2C bus (PLL). Below you will find info on one of the Tuners in use. General description of UV1316: The UV1316 tuner belongs to the UV 1300 family of tuners, which are designed to meet a wide range of applications. It is a combined VHF, UHF tuner suitable for CCIR systems B/G, H, L, L�, I and I�. The low IF output impedance has been designed for direct drive of a wide variety of SAW filters with sufficient suppression of triple transient. Features of UV1316: 1. Member of the UV1300 family small sized UHF/VHF tuners 2. Systems CCIR: B/G, H, L, L�, I and I�; OIRT: D/K 3. Digitally controlled (PLL) tuning via I2C-bus 4. 5. 6. 7. Off-air channels, S-cable channels and Hyperband World standardised mechanical dimensions and world standard pinning Compact size Complies to �CENELEC EN55020� and �EN55013�

Pinning: 1. Gain control voltage (AGC) 2. Tuning voltage 3. I²C-bus address select 4. I²C-bus serial clock 5. I²C-bus serial data 6. Not connected 7. PLL supply voltage 8. ADC input 9. Tuner supply voltage 10. Symmetrical IF output 1 11. Symmetrical IF output 2

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4.0V, Max: 4.5V Max: 5.5V Min:-0.3V, Max: 5.5V Min:-0.3V, Max: 5.5V 5.0V, Min: 4.75V, Max: 5.5V 33V, Min: 30V, Max: 35V

3. TDA988X
The TDA9885 is an alignment-free single standard (without positive modulation) vision and sound IF signal PLL. The TDA9886 is an alignment-free multistandard (PAL, SECAM and NTSC) vision and sound IF signal PLL demodulator for positive and negative modulation including sound AM and FM processing. Both devices can be used for TV, VTR, PC and set-top box applications.

4. MULTI STANDARD SOUND PROCESSOR
The MSP 34x0G family of single-chip Multistandard Sound Processors covers the sound processing of all analog TV-Standards worldwide, as well as the NICAM digital sound standards. The full TV sound processing, starting with analog sound IF signal-in, down to processed analog AF-out, is performed on a single chip. Signal conforming to the standard by the Broadcast Television Systems Committee (BTSC). The DBX noise reduction, or alternatively, MICRONAS Noise Reduction (MNR) is performed alignment free. Other processed standards are the Japanese FM-FM multiplex standard (EIA-J) and the FM Stereo Radio standard.

5. AUDIO AMPLIFIER STAGE WITH TDA7299
The TDA7299 is an audio class-AB amplifier assembled in SO package specially designed for sound cards application. By utilizing two TDA7299, chassis operates as a stereo TV set. TDA7299 has stand-by feature

1 15� TFT TV Service Manual 24/10/2003

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