Circuit Description; Horizontal Output - Sanyo C14EA80 Service Manual

CIRCUIT DESCRIPTION
1.POWER SUPPLY
2.IF & DEFLECTION (TDA8361)
3.VIDEO CHROMA & R.G.B. (TDA8361)
4.AUDIO OUTPUT(AN5265)
The audio signal output from pin50 of IC 101 is input to
pin2 of IC171 and passes through the pre-amplifier circuit
and drive circuit, after which it is input to the audio
amplifier. The audio amplifier is an SEPP (single-ended,
push-pull) OTL type and output to pin8 to directly drive
the speaker.
5.VERTICAL OUTPUT (LA7832)
An IC (LA7832) is used for the vertical output circuit in
this chassis. The vertical drive pulse from pin43 of IC101
is input to pin4 of 1C451. This pulse drives 1C451, and
vertical scanning is performed. In the first half of
scanning a deflecting current is output from pin2 and
passes through the following path:
Vcec(B4) — D451 — pin3 — pin2 —~ DY — C461 =
VR431/R459. An electric charge is then stored in C461.
In the last half of scanning the current path is C461
— DY
— pine > pint — VR431/R459 — C461. In this way, an
amplifying sawtooth waveform current flows directly to
DY to perform electron beam defection. Next, in the first
half of the banking period the vertical drive pulse
suddenly becomes OFF, and in order to reduce the
current flowing to DY, the current path becomes as
follows by the inductance of DY:
6.HORIZONTAL OUTPUT
A horizontal oscillation signal is output from pin37 of
1C101 and switches the drive transistor Q431. This
switching signal is current amplified by the drive
transformer T431 and drives the output transistor Q432.
When Q432 becomes ON, an amplifying current flows
directly to DY through C441/442 + DY +
0432 — GND,
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