20/21V-J100M
20/21V-J200S
INSTALLATION AND SERVICE INSTRUCTIONS
Note: (1) When performing any adjustments to resistor controls and transformers use non-metallic screwdriver
or TV alignment tools.
(2) Before performing adjustment, the TV set must be on at least 15 minutes.
CIRCUIT PROTECTIONHIGH VOLTAGE CHECK
The receiver is protected by a 3.15A fuse (F701),High voltage is not adjustable but must be checked
mounted on PWB-A, wired into one side of the Ato verify that the receiver is operating within safe andC
line input.efficient design limitations as specified checks should
be as follows:
X-RADIATION PROTECTOR CIRCUIT TEST
1. Connect an accurate high voltage meter between
After service has been performed on the horizontalground and anode of picture tube.
deflection system, high voltage system, B + system,2. Operate receiver for at least 15 minutes at 110 ~ 220V
test the X-Radiation protection circuit to ascertain
proper operation as follows:AC line voltage, with strong air signal or properly tuned
in test signal.
3. Set service mode on (See next page.), and select
1. Apply 220V AC using a variac transformer for accurateservice adjustment "S19" and Bus data "01" (Y-mute
input voltage.
2. Allow for warm up and adjust all customer controls foron).
4. The voltage should be approximately 20V-J100M /
normal picture and sound.J200S 26.5kV 21V-J100M/J200S 27kV (at zero
3. Select a local channel.beam)."
4. Connect a digital voltmeter to TP653 and make sure
If a correct reading cannot be obtained, check circuitry
that the voltmeter reads 20.6 ?1.5V.for malfunctioning components. After the voltage test,
5. Apply external 26.8V DC at TP653 by using an externalmake Y-mute off to the normal mode.
DC supply, TV must be shut off.
6. To reset the protector, unplug the AC cord and make a
short circuit between TP651 and TP652. Now make
sure that normal picture appears on the screen.
7. If the operation of the horizontal oscillator does not
stop in step 5, the circuit must be repaired before the
set is returned to the customer.
+115V DC Regulator Adjustment
The +115V DC Adj. control (R721) is adjusted at the
factory. However, should readjustment be required,
proceed as follows:
1. Actuate the receiver with 220V AC input voltage.
2. Select a good local channel.
3. Connect positive lead of digital voltmeter to R603
TP751 (positive side) on PWB-A; negative lead to
chassis ground.
4. Adjust R721 to obtain a +115V DC reading.
Caution : The reading should be within +115V ?
1 V DC to ensure normal function and
circuitry reliability.
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ACEC
