Smear the solder pads with flux, place the resistor in position and heat it until it sits down comfortably. If you have a hot air station you could now use it.
(I would stick to old fashioned tin-lead solder - it works much better.) Now do the same on the resistor (if it has not yet leapt into the distance) or its wire-ended replacement if you cannot find another 10k surface-mount one. Each pad should now have a shiny rounded low mound of solder. Now, without much delay, touch the tip of the soldering iron on each pad. A little flux there as well, and a touch of solder on the tip. You can wipe it when hot on a damp rag, and it should look shiny. Can you go over the pads on which the resistor was soldered perhaps scraping lightly with the end of a knife (rounded, not pointed), and when clean solder or copper is revealed, smear a little flux on the pads, similarly make sure your soldering iron tip is clean. Good luck, Andrew.Ĭleanliness is everything. And it might be worth practising the repair on a scrap board first. Yes, a wire-ended component can certainly be used, but is, of course, more likely to be knocked off accidentally. Best to clean up afterwards with more alcohol and a toothbrush. With an ordinary small soldering iron, and old-fashioned tin-lead solder, and a steady hand, it is not too difficult. If you feel brave you could heat the board locally from underneath until the solder runs, but it is unnecessarily risky. (It will leap out of the tweezers if it gets half a chance.) Place the part in position, preferably apply a little flux (violinist's rosin dissolved in alcohol works fine).
Long delay between button press and power chime imac free#
If so nudge your replacement part free and pick it off with tweezers. and diodes can have the same footprint.) Heat the scrap board from underneath over an electric ring or with a hot air blower, and nudge a nearby component to see if it is loosened (solder melted). Find any fairly modern scrap pcb and look for a suitable resistor. But if part of a voltage divider, then important to get it about right. If just to protect an IC input from excess current it would be fairly non-critical - say 1k to even 10K.
Can you find another logic board to look at to read the resistance, or judge from the circuitry what it might have been for. The first requirement is someone else's reading glasses or find a pick-your-own type which you can wear over your own, to allow you to focus at about 6". Dealing with these minute things looks more daunting than it really is.
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