13VT-N200
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, TV set must be on at least 15 minutes.
CIRCUIT PROTECTIONHIGH VOLTAGE CHECK
The receiver is protected by a 4.0A fuse (F701), mountedHigh voltage is not adjustable but must be checked
on PWB-A, wired into one side of the AC line input.to verify that the receiver is operating within safe
and efficient design limitations as specified checks
X-RADIATION PROTECTOR CIRCUITshould be as follows:
TEST1. Connect an accurate high voltage meter between
ground and anode of Picture tube.
After service has been performed on the horizontal2. Operate receiver for at least 15 minutes at 120V AC
deflection system, high voltage system, or B+ system,line voltage, with strong air signal or properly tuned
test the X-Radiation protector circuit to ascertain properin test signal.
operation as follows:3. Set to Service mode on, "Mute" and bus data 1(Y-
1. Apply 120V AC using a variac transformer formute on).
accurate input voltage.4. The voltage should be approximately 25.4kV (at zero
2. Allow for warm up and using the remote controller,beam). If a correct reading cannot be obtained, check
set the brightness level and contrast level tocircuitry for malfunctioning components.
maximum.After the voltage test, "Mute" and bus data "0" (Y-
mute off).
3. Check the voltage of test point TP653. (ItOs voltage
should be about 10.1V DC.)
4. Apply external 13.1V DC at TP653 by using an
external DC supply. The increased voltage will cause
the horizontal oscillator to stop and the TV to shut
off.
5. To re-start the oscillator, remove the external DC
power supply and short together TP651 and TP652.
Once the TV set operates normally again, remove
the short between TP651 and TP652.
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