Read Sharp 76DW-18H (serv.man3) Service Manual online
Sharp Electronics (UK) Ltd
Technical Support
February 99
Page 35
SELF ASSESSMENT QUESTION ANSWERS
Section
Question
Answer
Name two conditions that will turn on
Q702?
Q702?
Standby & Over-current
What is the supply voltage to IC1001 during
standby?
standby?
Zero volts
What will be measured with a DVM at the
base of Q702 during over-current?
base of Q702 during over-current?
Zero volts
If Q703 is open circuit, what would happen
to the power supply frequency?
to the power supply frequency?
Power supply will stop oscillating
P
o
w
e
r S
uppl
y
If load increase on the power supply, what
will happen to the frequency?
will happen to the frequency?
Decreases, allowing more energy to
transferred across T701
transferred across T701
What is the default condition of IC6702 pin
15?
15?
Low.
If IC6702 pin 15 is high what will happen to
the Dolby power supply?
the Dolby power supply?
Turn off
Sl
a
v
e
Pro
ce
s
s
o
r
What type of device is IC6702?
Processor with a combine volatile Memory
What is the active level of IC1001 pin 78?
Low. (CTV will switch to standby)
Dat
a
Com
m
u
n
ic
a
ti
on
If the 100Hz PWB reset is permanently
high, what will happen to the line drive?
high, what will happen to the line drive?
Line drive will not start. Reset level is low
During 100Hz scan, what is the frame
frequency?
frequency?
25Hz, the number of fields per frame is
increase from 2 to 4 therefore frame
frequency dose not alter.
increase from 2 to 4 therefore frame
frequency dose not alter.
Why is the line frequency doubled?
Twice the amount of date within the 25Hz
frame to be displayed.
frame to be displayed.
100Hz
P
W
B
What is the difference in the number of
pixels (picture area) per line between NTSC
& PAL?
pixels (picture area) per line between NTSC
& PAL?
No difference, they both have 720 pixels per
line
line
