Zenith XBV243 series Service Manual page 32

TROUBLESHOOTING (CONTINUED)
3. RF/Servo Circuit
A.
CHECK POINT(General)
Does signal go "High"
to IC201 Pin194 when
power is on?
YES
Does signal pulse
input to IC201 Pins 58, 59
when power is on?
YES
Does
TTL pulse output to
IC201 Pins 140, 142?
YES
Is IC201
Pins 83, 84, 88, 89 voltage
about 2.2V?
YES
END
VR168 - 923-03485
ELECTRICAL
NO
NO
Check "2.µ-COM Part".
NO
33.8688MHz clock input
to IC201 Pin 63?
YES
Replace IC201
(IC206 soldering or IC defect).
NO
Check power circuit.
3-20
Does
NO Replace X301 or IC304
(30MHz clock defect)
D35E COMBO - ELECTRICAL