Sharp 51DT-25H (serv.man19) Service Manual / Technical Bulletin ▷ View online
Sharp Electronics (UK) Limited
Originator AvW Supervisor Approval Date / / Reference BW 100898
White – Carry out as required, Yellow – Carry out as required and whenever the unit comes in for service, Red – Carry out on all units
CTV980803
Month of Issue: August 1998
Classification: White
TELEVISION TECHNICAL BULLETIN
Page 1 of 2
MODELS
37DM23H
37DT25H
51D25H
SYMPTOM Transistors Q401 and Q801 may be damaged by intermittent electrostatic discharges
from the CRT. This normally results in a blank raster (no video).
CAUSE
Excessive voltages generated across the base-emitter junction of Q401 and/or Q801.
ACTION
Fit diodes across the base-emitter junctions of Q401 and Q801 as shown in the
diagrams below.
diagrams below.
REF NO
DESCRIPTION
PART NUMBER
PRICE CODE
D411
Didoe, 1N4148
RH-DX0045BMZZ
AA
D412
Diode, 1N4148
RH-DX0045BMZZ
AA
CF301 L202 D411
Q401 D412 C420
Location of Components on the Component side of the PWB
Sharp Electronics (UK) Limited
Originator AvW Supervisor Approval Date / / Reference BW 100898
White – Carry out as required, Yellow – Carry out as required and whenever the unit comes in for service, Red – Carry out on all units
CTV980803
Month of Issue: August 1998
Classification: White
TELEVISION TECHNICAL BULLETIN
Page 2 of 2
E
Q401
B
B
D412 C
R408
R407
R407
Q401
R407 D412
R408
E
E
C D411
E
C D411
B
Q801
Q801
Q801
D411
Physical Location of New Diodes and Modified Circuits
Display