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John Rumm John Rumm is offline
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Default Component level repair and desoldering

On 14/01/2012 03:32, NT wrote:
On Jan 14, 12:21 am, wrote:
In , John
writes



I was toying with doing a wiki article on component level repair of
electronic stuff, since there seems to be so much otherwise decent kit
that dies these days for silly reasons like failing capacitors etc.


A few random thoughts - more to follow

Repair would entail correct diagnosis of the fault


exactly, and thats where ukdiy often falls down, and beginners cant
generally do it on their own.


I don't think that anyone is suggesting detailed fault finding
techniques for digital electronics.

(which while not actually a massively difficult task with the right
equipment, its very easy to find yourself twiddling knobs on several
hundred grands worth of it in the process, which tends to put much of it
beyond most folks DIY budgets)

At the simplest level, a hell of allot of kit can be saved just by
spotting the caps that are bulging and spewing electrolyte all over the
place. If you want to get a bit deeper, then you can do plenty with a
multimeter, and even relatively specialist bits of kits like LCR
component analysers or ESR meters are not that expensive.

(I don't agree that ukdiy falls down on diagnosis either particularly -
we have some very good engineers here with plenty of experience in
relevant fields. That does not mean that all contributions or all advice
will be spot on, but its no reason to write it off either)

plated through holes, once the component lead is removed, if you then
reapply solder to the joint and can clean the hole out better with a
solder sucker


you can, but I've never seen teh point. Just heat the hole and push
the component lead through.


That works for many boards, but not all. In some cases a typical iron
delicate enough for the size of task can't supply the heat on a
multilayer board. That's where the hot air systems work well, either to
temper an area of board to give the iron a chance, or more typically on
their own just to reflow the obscured hole so it can be sucked clean.

--
Cheers,

John.

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