At 05:35 PM 10/21/04 -0700, you wrote: Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Ha! Go buy the CD manual set from the HP calculator museum or else go to E-bay and be ready to pay the collector's price for an original. Yes. Replace the cells with other nicad cells. Forget LiIon, NiMH and all the other types. Buy GOOD NiCads and they'll last for many years. My personal preference is the >>>>>>>>>> Japanese made <<<<<<<<<<<<<<<<<<<< Sanyo batteries. Don't let them substitute the Mexican made Sanyos or Chinese made trash!!!!! Don't let them tell you that even the Japanese marked batteries are made in Mexico of that the Mexican made bateries are the same as the Japanese made ones, THEY'RE NOT! FWIW I have a set of Sanyos that I bought in Thailand in 1974 that are still useable. The leaked electrolyte is potassium hydroxide. The blue corrsion is double carbonate salt of copper (from the battery contacts) and potassium. I forget the exact chemical formula but it's something like CuKCO3. The hydroxide reacts with carbon dioxide in the air and forms a carbonate. The best thing that I've found to clean it up is Lime-Away. It's a product that's sold in the gorgery stores here in the US and is used to clean up lime and mineral deposits/stains in sinks, showers, toilets, etc. The main ingrediant in it is phosphoric acid. Put it on full strength and let it soak for a few minutes, then scrub it (I use an old toothbrush) to make sure all the corrision is removed then wash well with clean water. I scrub it while rinsing to make sure that I get ALL of the Lime-Away out. Then dry WELL. If you don't get all the Lime-Away out and dry it well it makes purple stains on the gold contacts when you apply electric power. Joe