Howdy all! I'm the new owner if one of the coolest "Calculators" HP ever made. Everything generally works but I would need a new capstan (rubber is now sticky) to use with the tape cartridge. I am running into a hard time tracking down information on using it though, so if anyone can help fill in some gaps, that would be great! I'm looking for: - A manual for HPL, the language used to calculate. Things like for loops don't seem to work, but 'dsp' 'gto' and variable assignment do. - Manuals for any and all of the cartridges, and how to use them - Ideas on replacing the capstan - Ideas on refurbing the tapes (there's a rubber band equivalent to drive the tape on both sides, these have lost their stretch) - Specs for the I/O, as I would love to make custom I/O for it. I would also love to be able to create new cartridges, but I'm not willing to sacrifice any of my existing cartridges to Reverse Engineer them. I have the Plotter / GPIO Cartridge, the Mateix cartridge and the Strings Advanced Programming. Trying to track down an Assembly cartridge or any others. Thanks! Any info is appreciated! ~ Andre