27R-S200, 27R-S400
27R-S450, CR27S20
CSR20027
INSTALLATION AND SERVICE INSTRUCTIONS
Note: (1) When performing any adjustments to resistor controls and transformers use non-metallic
screwdrivers or TV alignment tools.
(2) Before performing adjustments, the TV set must be on at least 15 minutes.
CIRCUIT PROTECTIONHIGH VOLTAGE CHECK
The receiver is protected by a 4.0A 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 safeC
line input.and 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 horizontal
ground and anode of picture tube.
deflection system, high voltage system, B+ system,
2. Operate receiver for at least 15 minutes at 120V AC
test the X-Radiation protection circuit to ascertain
line voltage, with a strong air signal or a properly tuned
proper operation as follows:
in test signal.
3. Enter the service mode and select the service
1. Apply 120V AC using a variac transformer fadjustment "V18" and Bus data "01" (Yor-mute on, CRT
accurate input voltage.Cut Off).
2. Allow for warm up and adjust all customer controls4. The voltage should be approximately 29.0kV (at zero
for normal picture and sound.beam).
3. Receive a good local channel.If a correct reading cannot be obtained, check circuitry
4. Connect a digital voltmeter to TP651 and make surefor malfunctioning components. After the voltage test,
that the voltmeter reads 13.2 ?0.7V.make Y-mute off to the normal mode.
5. Apply external 16.3V DC at TP651 by using an
external DC supply, TV must be shut off.
6. To reset the protector, unplug the AC cord and plug
the AC cord power on. 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.
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ACEC
