Originally Posted by JACK98
One of the reasons whilst i asked the quest,today i sat taking caps off the A1200 *the method of using a gentle twist with pliers does work!*,and thought of recapping, and then in future of having to replace something else on the same board like a comp chip just put me off and make me rather use emulation on a modern pc.
It's not hard, but it's very risky if you have no experience with it!
- Aluminium foil
- Soldering iron with a small pointy tip
- Soldering tin (preferrably with lead)
- Pair of tweezers that can open wide
- SMD flux
- Desoldering wick
Apply flux to all the PLCC pins. Wrap the PCB with two layers (or more) of aluminium foil and uncover the PLCC, this prevents other components to overheat and eventually melt (!). Pre-warm the PCB (just sweep around even though the aluminium foil is there) with the heatgun on low temp, then focus in circles on the PLCC for a while. You might need to switch to a higher temp for a short period of time, but only when the chip is heated up.
Then fast as a mouse take a pair of tweezers and lift up the chip, it is supposed to lift up with ease. If it didn't lift up, then don't
force it up. Start over again with the heatgun. Lateron use isopropanol alcohol to clean the flux residue, desoldering wick to remove the solder residue and use isopropanol again to clean up. Ready for new chip!
Soldering the new chip is more hard.. But a working solution is to add flux to all the solder pads then allign the PLCC correctly (have the dot mark in mind, align pin 1 with the "pin 1" icon on the PCB). When the pins match up to the pads, carefully add solder to each "corner" pin... Now that the PLCC is not moving, add some more flux to the rest of the pins and start soldering. Warm the pins and add solder to it, the solder with hopefully travel to the pads as well. If you get way too much, try to drag the soldering iron on the pins to remove the excessive solder. Don't be too fast or stressed - it's not hard at all as long as you're calm.
When it's done, look closely for any eventual shorts or non-contacts. Use isopropanol again.
Good as new