JVC HR-D540EE - Timer Circuit

2.2
SWITCHING
REGULATOR
CIRCUIT
Note:
Unless
otherwise
specified,
all
test
points
and
adjustments
are
located
on
the
SWITCHING
REG
ULATOR
board.
check
Point
|
4
tment
re]
tm
[ncn
[RSS|
sr
te
R37
eREC
1)
Connect
a
digital
voltmeter
between
TP1
and
(5
V
DC)
eSOURCE
SEL:
TUNER
TP-GND.
2) Record in the TUNER mode, adjust R37 for
5.3+0.05 V.
2.3 TIMER CIRCUIT
Note:
Unless
otberwise
specified,
all
test
points
and
adjustments
are
located
on
the
TIMER
board.
eE-E
Note:
For
below
adjustments
use
1:1
probe
with
aoe
clock)
input
capacitance
less
than
100
pF.
1) Connect a frequency counter between 1C1-16
and GND.
2) Short TP1 to GND, then short the kads of ca-
pacitor C3 once in order to reset ICi. All FDP
Segments and power LED are on.
3) Adjust C6 for 2048.000 + 0.002 Hz (488.2808
to 488.2818 us).
2-3