Toshiba 27A10 Single Horizontal Line

[John Keiser]

8 year old TV. Nice picture.
Began displaying a brighter line about 5 inches from the bottom
occassionally but the picture was otherwise OK.
I doubted my ability to track that down and let it go.
Too subtle. Too intermittent.
Tonight, entire picture collapsed into a single horizontal line.
I opened up the case looking for the vertical output section and a bad cap
or burnt component. Nothing seemed visually amiss.
Plugged the set in and it works fine again.
I now assume a bad solder joint.
Can anyone suggest which components [by schematic number, if possibe] might
need a prophylatic re-solder?
Thank you.

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[Ulrik Smed]

Samuel M. Goldwasser wrote:

"John Keiser" <john.keiser2@hawaiiantel.net> writes:

8 year old TV. Nice picture.
Began displaying a brighter line about 5 inches from the bottom
occassionally but the picture was otherwise OK.
I doubted my ability to track that down and let it go.
Too subtle. Too intermittent.
Tonight, entire picture collapsed into a single horizontal line.
I opened up the case looking for the vertical output section and a
bad cap or burnt component. Nothing seemed visually amiss.
Plugged the set in and it works fine again.
I now assume a bad solder joint.
Can anyone suggest which components [by schematic number, if
possibe] might need a prophylatic re-solder?

You've pretty much diagnosed it. A bad solder joint in the vertical
section, may even be the connector to the vertical deflection yoke
winding. That should be easy to find, check it, then trace back to
the vertical output.

If the vertical output is one of those vertically mounted ICs on a heatsink,
it's very likely one or more of its pins that need resoldering. They tend to
break the solderings especially at the pins closest to the ends of the IC.
Just resolder them all. Sometimes the cracks are so thin it's hard to see
them, but if you pull the pins a bit with a fingernail, they often become
clearly visible.

--
Ulrik Smed
Aarhus, Denmark

 

[John Keiser]

I appreciate the confirmations.
I reflowed a few joints but really couldn't see any dull or brittle or
cracked connections.
The components seem sturdy and I was surprised to see Toshiba designed the
board with 3 fuses. Seems well made for this day and age.
I'll like to keep this going.
If anyone is familiar with this model and can suggest which specific part
number is the more likely culprit, I will rertain for future use should this
fail again.
Thank you.
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[Samuel M. Goldwasser]

"John Keiser" <john.keiser2@hawaiiantel.net> writes:

8 year old TV. Nice picture.
Began displaying a brighter line about 5 inches from the bottom
occassionally but the picture was otherwise OK.
I doubted my ability to track that down and let it go.
Too subtle. Too intermittent.
Tonight, entire picture collapsed into a single horizontal line.
I opened up the case looking for the vertical output section and a bad cap
or burnt component. Nothing seemed visually amiss.
Plugged the set in and it works fine again.
I now assume a bad solder joint.
Can anyone suggest which components [by schematic number, if possibe] might
need a prophylatic re-solder?

You've pretty much diagnosed it. A bad solder joint in the vertical section,
may even be the connector to the vertical deflection yoke winding. That
should be easy to find, check it, then trace back to the vertical output.

--
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