ELECTRONICS CORNER
My Repair Jobs
General information
Job Number |
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0009-29 |
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Equipment type |
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TV Colour 24 inch |
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Maker + Model # |
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Grundig CUC 2410 |
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Made in |
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Comments |
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Recommended by Cousin Rita ! |
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Symptoms observed
BAD |
1 |
Yellowish / Green
Picture, little Red |
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GOOD |
1 |
Sound and Raster OK |
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2 |
Good tuning |
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3 |
Good IR, sound and
picture controls |
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Repair notes
Full repair description and observations |
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1 |
It was obvious that the
blue section is not operating. While testing for some dry joints, on the RGB
board, and CRT plate, the Blue appeared a normal coulored picture appeared.
The TV was let to operate for 3 days, and the picture never turned to yellow
again. It was delivered back to the client |
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2 |
After 1 day, the client
phoned that the picture is becoming yellowish again. This time inspection and
servicing was done at the client house itself. It was noted that there was no
150V on the collecter of the Blue Video driver, but on cheking further more,
the picture came again normal. On tempering the CRT plate sometimes, the
yellow picture forms again and turns normally later with obvious location of
the dry joint. |
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3 |
It was an obvious sign
of a dry joint, but there was no clue on which part of the circuit it is.
Hence most all components forming part in the blue section of the RGB plate
was desoldered and soldered again. The problem was fixed |
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4 |
Also I replaced the
Video amplifier of the blue stage with the green one so that if the video amp
is the faulty component, now it lies in the green section, and if it fails, a
violet picture will result this time. |
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5 |
After few days, the
client complained that the picture has turned VIOLET!!! I went again to her
house and repalced all the 3 video amplifiers. I wanted the GF759 transistors
but the Grundig parts department (Mirald) gave me the BF881 as a replacement. |
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6 |
The TV was fixed
permanently this time. |
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Repair summary |
BLUE VIDEO AMPLIFIER FAILING
(OPEN CIRCUIT) AT RANDOM INSTANCES. |
Precautions, fouls and advises |
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1 |
When a problem seems to
fix by itself, almost always, it will re occur. Hence one must check many
times before handing the repaired item to the client to avoid disappointful
surprizes. |
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2 |
When going to make
repair service at the location of a client be sure to take all neessary tools
and parts with you. In this occasion I forgot to take the solder! |
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