Abnormal Vertical Scanning; Side-Pin Cushion Distortion; Poor Focus - ViewSonic P774B-2NT Series Service Manual

6-6 ABNORMAL VERTICAL SCANNING

1. ABNORMAL VERTICAL SIZE
READJUST V-SIZE FUNCTION VALUE
CHECK THE IC601 PIN 2 ABOUT 11.8V
PIN 4 ABOUT -12V
OK
CHECK VERT. OSC CIRCUIT
OK
READJUST V-SIZE FUNCTION VALUE
2. VERTICAL CENTER
READJUST V-CENTER

6-7 SIDE-PIN CUSHION DISTORTION

READJUST SIDEPIN
READJUST FOCUS CONTROL
NG
NG
NG
NG
CHECK IC401 AND IC601
RELATIVE CKT
NG

6-8 POOR FOCUS

NG
18
CHECK D601, C605
RELATIVE CIRCUIT
CHECK THE VOLTAGE OF IC101
RELATIVE CIRCUIT
CHECK IC401 PIN 20, 21, 22, 23
RELATIVE CIRCUIT
CHECK IC401, Q404, Q405, Q406
RELATIVE CKT.
CHECK FOCUS CONTROL UNIT,
FOCUS LEAD WIRE, CRT SOCKET & CRT