Sony SDP-EP9ES, Service Manual

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SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs, screws,
and all other exposed metal parts for AC leakage. Check leakage as
described below.
LEAKAGE
The AC leakage from any exposed metal part to earth Ground and
from all exposed metal parts to any exposed metal part having a re-
turn to chassis, must not exceed 0.5 mA (500 microampers). Leak-
age current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers’ instructions to use these
instruments.
2. A battery-operated AC milliammeter. The Data Precision 245 digi-
tal multimeter is suitable for this job.
3. Measuring the voltage drop across a resistor by means of a VOM
or battery-operated AC voltmeter. The “limit” indication is 0.75
V, so analog meters must have an accurate low-voltage scale. The
Simpson 250 and Sanwa SH-63Trd are examples of a passive VOM
that is suitable. Nearly all battery operated digital multimeters that
have a 2V AC range are suitable. (See Fig. A)
Fig. A. Using an AC voltmeter to check AC leakage.
To Exposed Metal
Parts on Set
0.15
µ
F
1.5k
Ω
AC
voltmeter
(0.75V)
Earth Ground
SECTION 1
SERVICING NOTE
RV901 of Main Board
RV901 of the main board requires no adjustments. Please note that it
should be dixed to mechanical center position when you moved and
do not know origin position.
Connection and Test Disc
Connection of this unit to a AC-3 Dolby surround equipment will
realize outstanding sound playback.
Check if the respective surround channel outputs are playing back
normally by the following method.
Jig :
Discription Part No.
AC-3 TEST LD J-2501-132-A
Connected Equipment:
AC-3 LD player
(This unit is also compatible with the digital versatile disc player
(DVD). The DVD must be checked with the LD player using all
the circuits of this unit.)
Connecting Method:
AC-3 compatible
LD player
AC-3 RF output terminal Coaxial digital
connecting cable VMC-10G, etc. (Optional)
Unit
AC-3 RF
output terminal AC-3 RF
input terminal
Checking Method:
Play back a test disc of the LD player, and check if the contents
recorded on the disc case (printed on the disc case) are played
back normally.