Re: Help with SMD Components


"Arfa Daily" <arfa.daily@xxxxxxxxxxxx> wrote in message
news:mP%Qi.20744$z05.18408@xxxxxxxxxxxxxxxxxxxxxxx

"Michael Kennedy" <Mikek400@xxxxxxxxxxxxxxxxxxx> wrote in message
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Oops.. typo in the second URL

it should be

http://onetechcomputers.com/ipod2.JPG


There are 'electrolytic' caps on that board in a format different from the
cans you are expecting, although they are probably actually solid
tantalums rather than traditional wet electrolytics. An example is the
black block marked "C224" at the bottom left of the first picture, and the
yellow "C114" at the bottom left of the second picture. Generally, I have
found this type of cap to be pretty reliable in this type of application.
Solid dielectric high value caps, don't suffer from the same physical
problems as wet types.

If it is a genuine electronic problem, I fear that it is unlikely that you
will ever get to the bottom of it, or if you do, be able to repair it. I
used to do a lot of small SM stuff like this in the form of Sony personal
minidisc players, and most of the intermittent problems came down to bad
BGA LSI 's (or the soldering under them) or bad thru' plated holes,
neither of which was realistically repairable in a 'traditional' workshop
environment.

It might be worth just checking that there is no problem with the battery
connections, the battery itself, or the charging / docking connector.
Beyond that, unless you can find something really obvious, I think that
the item is coming to the end of the line ...

Arfa


Thanks Arfa... I had an assumption that a fix was far fetched since this is
such a small piece of equipment. This one used to work great now it is
intermittant, I have another ipod that the menut button doesn't work but is
otherwise functional... The one with the non working menu button is very
strange since if you shine an IR diode into the vias behind a large chip the
menu button is activated. I discovererd this while inspecting the board
under my desk lamp wich emmits a lot of IR. I glued an IR diode onto the
board and wired it to the menu switch and it was an ok fix. It doesn't
always work, but does most of the time. an intermittant menu button is
better than none at all..

Too bad these boards are double sided, I'd try reflowing it in a toaster
oven.

Mike


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