ELECTRONICS CORNER
My Repair Jobs
General information
Job Number |
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0108-27 |
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Equipment type |
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Televsion - 19 inch |
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Maker + Model # |
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Seleco 19SM422 |
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Made in |
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Comments |
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Symptoms observed
BAD |
1 |
On turning on from stand
by, a large spark sound is heard from inside, and the TV shuts off |
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GOOD |
1 |
Powers up to stand by
mode |
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Repair notes
Full repair description and observations |
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1 |
When opened, it was
noted that the spark came from the Focus part of the CRT base on the RGB
plate. |
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2 |
To ensure that the
sperking is not due damage/dirt in the CRT base, it was desoldered out and
inspected. The focus spark gap (at the CRT base) was wipe-cleaned.
No obvious abnormalities were observed in the CRT base and
was inserted back. On switching on, the fault persisted and a spark
was formed oround the crt base. |
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3 |
The Focus anode was
removed from the CRT palte and insulated for safety purposes. On switching
on, the spark was first seen around the G2 connection, and then around the
CRT plate. |
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4 |
The G2 wire was removed
from the RGB plate and
insulated. On switching on, the spark was now seen from the
LOPTX body (on the main board) to the surrounding earth barrier, in a form of
a ‘cloudy’ spark. It was obvious that the LOPTX was faulty. |
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5 |
The HR equivalent was
found from the HR diemens internet site – which resulted to be an HR 7169.
Mireland did not have, but Mapp (the HR agent) did. |
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6 |
The LOPTX was replaced,
with obvious measure of discharging the EHT capacitor for reasons of safety. |
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7 |
On switching on, no
sparks were formed, and a raster was developed. |
Repair summary |
LINE OUTPUT TRANSFORMER FAULTY |