HP19c Printer Disassembly

[jjohnson873]

I was able to completely disassemble the HP-19c printer and reassemble it again. One word of caution, there is an extremely small spring used to apply pressure to the printhead bar. This spring is extremely difficult to reassemble and it will certainly fly off to parts of your room unknown... more than once. I spent considerable time looking for it when reassembling the HP-19c printer. There is really no reason to disassemble the printer down to this level. If you've removed the ribbon cable from it's connector, you can remove the thermal printhead without removing anything else by releasing the small plastic clip holding the ribbon cable to the printhead metal bracket. Then you can just pull out the printhead from the printhead assembly. If you need to, you can remove the printhead unit by removing two circlips, but it's unlikely you'll need to do that if the printhead is moving smoothly.
I had measured this printhead from the ends of the ribbon cable. It only showed 4 of the 7 thermal print pins with a resistance. But when I pulled out the printhead and measured near the bottom of the printhead, on the frontside, per Bernhard's suggestion, I found that the printhead measures 10.8 ohms on every thermal print pin to ground! This indicates that the printhead itself is good. I'm going to have to figure out how to check the ribbon cable for breaks.

HP-19c printer parts shown in attached pic.