Sony KP 48S70, Training Manual

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Convergence Out
Overview
The Convergence Out circuit amplifies the horizontal and vertical conver-
gence signals that are output by the BD Output circuit for each color. The
circuit below shows the IC5005 Convergence Amp. IC5006 is another
Convergence Amp. It is not shown here because its circuitry is identical
to the IC5005 circuit.
Regi Mute
When the set is first turned ON, a Regi Mute signal is required because
the BD board outputs a High signal from the six convergence outputs for
three seconds. If all Highs were output from the BD board simultaneously,
it would probably result in a problem on the +/- 22 volt lines.
When the set is initially turned on, a LOW is output from the BD board to
the A board. The A board transfers this LOW through CN5011/8 to the D
board. This LOW is applied to the base of Q5024, keeping it OFF. If
Q5024 is OFF, then Q5025 and Q5027 are also OFF. This causes IC5005/
12 and 13 Mute to be 0 volts. This will mute IC5005 and it will not output
any signals. After three seconds the Regi Mute output will go HIGH. This
causes Q5024 to turn ON. This will cause Q5025 and Q5027 to turn ON.
This places –19 volts on IC5005/12 and 13 which enables the outputs of
IC5005.
Convergence Amp
IC5005 Convergence Amp contains three amplifiers. Each of these am-
plifiers contains two inputs, a Non-inverting and Inverting, and one out-
put. If we look at the first amplifier inside IC5005 we see that the vertical
green signal is input to IC5005/4 Non-inverting Input. It is output from
IC5005/22 through PS5006 to the Green Vertical Sub Yoke. The signal
passes through the yoke and is returned to IC5005/5 Inverting Input via
R5017. The other two amplifiers in IC5005 work exactly like the circuit
described above.