Flux - rubbing alcohol (standard grocery store stuff) and cotten swabs and/or those acid brushes (or just a small stiff paint brush) work wonders. Overnight soaking doesn't help, re-heating the flux with an iron doesn't work. Just good ol' elbow grease.
What kind of LCD do you have that has 24 pins? Is this one of those 7-segment types?
You should look into the whole Nokia-knock-off LCDs (check
www.sparkfun.com). Easy to control, 6 lines from the PIC, 130x130 pixels, and in color. I'm having a blast with mine.
Bookmarks