No Operation, Power Led Off - NEC N9902 F-1 Service Manual

2. NO OPERATION, POWER LED OFF

POWER SW
TURN OFF
CHECK
F101
CHECK
Q101
CHECK
U101
U101 PIN6
PULSE O/P
POWER SW
TURN ON
1. DC P/S O/P VOLTAGE SET AT 17V,CURRENT SET
AT 200MA. POSITIVE CONNECT TO C109"+".
NEGATIVE CONNECT TO C105"-".
2. SCOPE SET AT 10V/DIV, 10US/DIV, PROBE
CONNECT TO Q101-GATE AND C105"-".
CHECK
U101 PIN 7 VCC
NO
PIN 4 SAWTOOTH
FAILURE
R111, ZD103
18