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Default LCD TV Repair Training Manual/Book Source


wrote in message
...
Hi,

A few months ago I looked for a LCD TV repair training manual/book
at Amazon, Border's, Walden's, etc.

Do you know of a source for such a manual/book?

Thank You in advance, John

PS, Remove "ine" from my email address


To be honest, there's not an awful lot to repair on them. By far and away,
the two commonest problems are the power supplies, and backlight inverters.
The power supplies are just generally just multi-stage switchers (standby
supply, PFC supply and main supply - that's effectively three mostly
independant switchers on one board). Most failures are fairly obvious. Chips
with the tops blown off, bulging or open circuit caps, bad lead-free joints
etc. Most boards have 'repair kits' available for them, where you just
replace everything that comes in the kit, and turn back on. 99% of cases,
that is then an end to the problem. Most TV switchers are pretty well
behaved, once they have been properly repaired. Also, there are not all that
many different types. An awful lot of LCD TVs are just badged from a few
different manufacturers, and you will quickly see similar if not identical
modules popping up in sets that are completely different on the outside.

Worst case, if you really can't fix a particular power supply, the whole
module is often available at an unrealistically cheap price from either the
manufacturer, or their spares agent. If the name on the front is something
obscure, you may well recognise the supply as being the same as one fitted
to a major brand set. You can then just buy one of those instead.

The biggest problem is schematics. Even if you can get a schematic set for
the whole TV, you will often find that the PSU is shown just as a 'block'.
Spares can also be a problem, with 'obscure' surface mount devices often
being used. This ceases to be a problem if you use a repair kit, but in some
cases, these are 'shotgun', and may contain devices to fix several different
common problems, and thus cost a fair bit more than you would pay trade for
just the devices that are *actually* faulty. That said, unless you are very
experienced with switchers, I would always recommend replacing ALL of the
items that come in the kit, as sometimes, some little diode or whatever,
that appears to have nothing at all to do with the components that you
*have* found faulty, is actually the original cause of the cascade failure
that you thought that you had gotten to the bottom of ... :-(

Backlight inverter boards suffer from bad joints, bad transistors, bad
transformers, and bad caps for the most part. Again parts can be a problem,
and it is often better to source a replacement board, then keep the old one
to cull parts from for the future.

Other than that, there's not too much else that you're going to be able to
repair. For sure, you can get audio IC problems, and cap failures and so on
in other areas of the sets, but in general, main board failures are going to
be beyond the diagnostic abilities of a 'normally' equipped and trained
engineer.

Hope that is of some practical help to you.

Arfa