Haier HS-2190, Руководство по обслуживанию

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Reference Voltage(V) Reference
Resistance(K
Ω
)
Pin Function
With signal
Without signal
Forward
Backward
38 Data bus control 3.2 3.0 0.4 0.5K
39 Vacant pin 0 0 0 0
40 Vacant pin 5.9 5.9 7.9 7.9
41 Vacant pin 0.1 0.1 8.0 8
42 Power supply 5.2 5.2 1.5K 27
N101 LA7910
Reference Voltage(V) Reference
Resistance(K
Ω
)
Pin Function
With signal Without
signal
Forward Backward
1 Output (BU) 0 0 4.3 4.3
2 Output (BH) 0 0 4.6 4.6
3 Control input 0 0 18 22
4 Control input 1.6 1.6 43.4 0.5K
5 Grounding terminal 0 0 0 0
6 Power input terminal 1 10.4 10.4 22 18
7 Output (BL) 8.8 8.8 3.0K 5.6K
8 Vacant pin 3.4 3.4 4.6K 0
9 Power input terminal 2 8.8 8.8 1.2 1.3
3. Signal processing
(1) Picture intermediate signal processing
Having been under tuning and selective calling, high frequency amplification and frequency
mixing in tuner U101, the high frequency signals are output through the intermediate
frequency signal output terminal (IF) of U101 to the base electrode of intermediate frequency
pre-amplifier V101 via the coupling matching network. The intermediate signals are added to
Pin 6 and 7 of the symmetric terminals of the intermediate difference channel of the TV
signal monolithic processing circuit N201 (TB1238AN). The intermediate signals are
amplified in N201 and the PLL picture modulated. The mixed signals of picture video and the
second sound are output from Pin 47 and then divided into two.
(2) Picture signal processing
The signals from Pin N201 (47) go through the sound intermediate frequency wave trap Z268
(D/K system) or Z265 (B/G system) and the emitter follower V212 so that the video complete
TV signals are got out and sent to TV/AV electronic switch circuit through Pin (43). One part
of the output signals go into the video signal processing circuit, the other go in the color
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