Commodore C64 Service Manual page 11

C64 CIRCUIT
THEORY
1,47
AC
A5/AI3
A4/A1Z
Vdd
SYK1C15.
LUM
A3/AM
A2/AIO
AI/A9
AO/A8
A
EC
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ELECTRO-
LYTIC
ELECTROLYTIC
Q>
5 8
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C35
+V RF
N
MODULATOR
CASE
4
VIDEO AUDIO
5 Pin
Video and Audio Output
Circuits.
Pin
1
5
of
the
VIC
IC
is
the
sync/luminance output. Pin
1
4
is
the color
output.
A
composite
video out-
put
is
created
by mixing sync/luminance and
color.
The
composite output
is
applied to
the
RF modulator,
and
also
passed
to
the
monitor connector
CN5
on
pin 4.
The
color
output
is
not
made
available
on
the
monitor connector
CN5
as
on the 8
pin
version,
and the
RF
modulator mixes audio with the
com-
posite
video producing the
TV
RF
output, unlike the
8
pin
version
RF modulator which
creates the
composite video output.
9