Restoring HP-65

[burkhard]

Alberto,
Thanks for recounting your adventure with Edoardo here... it looks like a good father-son project! I need to be doing the same with my own kids.

One question... lemon juice makes me a little nervous. Certainly it's acidic, but it also carries a lot of sugar that I don't think would be great to get all over the board. We tend not to think of lemon juice as being sweet but apparently on the same volume basic, it's got 85% the sugar of orange juice. White not white vinegar, which is otherwise pretty benign?

I had considered a USB or kit oscilloscope in the past, but the prices of real hardware digital scopes has gone way down and those are so much nicer. The Rigol 1054Z is particularly popular among electronics hobbyists right now: a 4 channel, 50 MHz for $US 350. Check some Youtube reviews; I don't have one myself, but am leaning. There are others as well; the market is getting more crowded.

Keep us posted! I've got a 65 I need to take apart as well, Besides the standard fun with the card reader, it's got some keys that I think need cleaning... feel fine, but hard presses required.