Desoldering/ component removal

hey guys,

I need to remove a sub-miniature audio transformer from a PCB. It should be a piece of cake and always has been in the past, but something's different about this one. At those odd times previously when I've done this, I've just used a soldering iron and a vacuum pump to melt the joints and suck off the solder. The pins are then free and the part almost drops off by itself. This one is not so simple, though. It's a double-layer board and the transformer is mounted directly on top of the traces that feed it. On the reverse side, I can see the end of the transformer's leads poking through just proud of where a pad would normally be, but in this case, there are no pads 'cos there are no traces; just tiny, isolated circles of solder around each lead-end. I guess I need to get at the actual solder joints proper on the top side, but the transformer is sat right on top of them making it totally impossible to even see the joints I need to get at! Whut gives here? Are these things deliberately designed to be unserviceable nowadays? Is that the idea? Bastard manufacturers want us to buy new stuff instead of fixing old? Sigh. Does anyone know a ruse to defeat this darstardly scam?

Reply to
Julian Barnes
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Diamond encrusted cutting wire?

Reply to
N_Cook

Hot air desoldering tool.

This one works nice:

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Consider adding ChipQuick to lower the melting point.

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And flux.

Reply to
tom

Probably.

Surely.

They're a PITA - IME at any rate. This is one of the better explanations on how to deal with them:

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Reply to
Cursitor Doom

The power suction jobs take some beating :-)

Reply to
Rheilly Phoull

If soldered rather than rf welded joints. A small length of tungsten wire from a smashed 40W mains lamp, crimped to thicker delivery wire. Varying current of a bench ps, find the current for dull red heat of the tungsten. Drape the tungsten wire over one of the pins , and a forcing blade/wedge in the gap while delivering heat to that pin and repeat?

Reply to
N_Cook

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