Haier HP-2999 Service Manual page 37

The data is to be tested under the mode of 49.75MHz PAL D/K and cylindrical color card, using a
model FLUKE 79 instrument.
Table 5
Pin Function
1 Sound output from right channel
2 Sound output from right channel
3 15V Power supply
4 Audio signal input of right channel
5 Blank pin
6 Bass signal input
7 POWER signal input
8 Ground
9 Ground
10 Blank pin
11 Blank pin
12 Audio signal input of left channel
13 15V Power supply
14 Sound output from left channel
15 Sound output from left channel
2.7 Analysis of field output circuit
Field sync signals separated from the mixed sync signals trigger the field frequency division system.
Once a certain sum of field sync pulse signals have been detected, the field frequency division
system will start in action. Of the field sync pulse signals which are obtained from frequency division,
one sub-flow will be fed into a sample pulse generator to, together with line feedback signal, produce
sample pulses necessary for the circuit.
Another sub-flow will be sent to field saw-tooth wave generator. The field frequency saw-tooth wave
that has undergone geometric processing will be sent from the (21) and (22) of N201 to the (1) and (2)
of the field output N301. The external resistor R228 39K
current to field saw-tooth wave generator , and the external capacitor C227 104 of the (26) serves
as the capacitor for field saw-tooth wave.
Field output integrated circuit N301 is a full bridge type current driving output circuit of with a bridge
type output manner, and field deflection coil is directly connected to the middle of output amplifier.
The positive and negative saw-tooth signals sent out from the (21) and (22) of N201will enter into the
(1) and (2) of N301 symmetrically, which, after being rectified and amplified by TDA8350Q, will be
sent out from the (9) and (5).
R301 (3K ) will transform input current into voltage, which will be compared with the voltage
produced when field scan current flows through a hunt resistor of R302(1.5 ) and R303(1.5 ), and
the result thus obtained will be a feedback voltage for TDA8350Q, therefore, field output current size
can be changed by changing R301. TDA8350Q has double power supplies, and the line return stroke
pulses sent out by the line output transformer T444 will be rectified and filtered to supply power to
Resistance to Ground R
Working
Forward Test Back
Voltage V
0 12.8K
0 12.8K
16.0 ~
0 86.2K
0 ~
4.4 108.8K
5.1 5.6K
0 0
0 0
0 ~
0 ~
0.7 86.3K
16.0 ~
8.0 12.7K
8.0 12.7K
of the (25) of N201will supply reference
36
Circuit Explanation
Test
12.7K
12.8K
0.94M
86.6K
~
107.6K
5.6K
0
0
~
~
86.5K
0.94M
12.7K
12.7K