Philips H8 - Page 38

A
DOES THE PROT-UP LINE GO
HIGH WHEN THE SET IS
TURNED ON? LOW IS 0
VOLTS.
DOES THE PROTN LINE
GO HIGH WHEN THE
POWER BUTTON IS
PRESSED?
NO
CHANGE THE SMALL
SIGNAL BOARD (SSB).
NO
CHECK 7464, 7467,
5431, AND RELATED
COMPONENTS.
YES
DOES THE BASE OF 7440 GO
LOWER THAN THE EMITTER
WHEN THE SET IS TURNED ON?
YES
DOES THE COLLECTOR OF
7408 GO TO 135 VOLTS WHEN
THE SET IS TURNED ON?
YES
CHECK 7408 .
NO
THE DAG (IBEAM) VOLTAGE IS
GOING LOW. CHECK 6439, 5431,
+200 VOLT SUPPLY, AND CRT
CIRCUITS.
YES
IS 7440 OPEN?
NO
REPLACE
YES
DOES THE BASE OF 7480 GO
LOW WHEN THE POWER
BUTTON IS PRESSED?
NO
CHECK 7480.
NO
CHECK 7470, 7478,
AND RELATED
COMPONENTS.
YES
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