Hi All,

Back in March, just over a month ago in fact, I posted a topic about my newly acquired HP-19C whose printer refused to behave.
Donald Williams and Katie Wasserman responded and helped me out.
As the discussion petered out, the action was left on me to try to make progress with connectivity and the power supply.

I am happy to report that, after cleaning up the inside, and managing to source a nice Sanyo NiCd battery pack which I soldered in directly, the HP-19C is now behaving very well.

Well, as well as can be for such a vintage calculator.

With the battery pack fully charged (it's 1000mAh), the calculator lasted over 9 hours running a closed-loop program before running out of juice (sometime after 9 hours; don't know when for sure). 7 hours after the start, I could still pause the program and do some printing successfully (that didn't work anymore past the 8th hour).

Again with the battery pack fully charged, I ran a test printing continuously for 25 minutes, over 1000 lines. I stopped it because I didn't want to wear it out ;-)

So a successful revitalisation of an old machine. Excellent!

Thanks for the help.

Thanks for the update and I'm happy to hear you've got it working again. I find that the 19C is the most fun HP calculator to play with. LEDs, printing and programming in such a small package!

-Katie