IL Thermal Printer (82162A) Paper Advance problems

[Peter Khor]

My 82162A IL Printer has problems advancing the paper roll; printing seems to work okay. When you press the paper advance key, or print something on the IL loop, it looks like the paper is only advanced half the intended height. ie, the next line with over print current line.

I've checked the side cam mechanism that advances the paper, and it seems to work fine. Is it suppose to be spring loaded?

The other option is that I have a spare 82143A that I can cannibalize the parts out of. It is difficult? I thot initially I would just swap out the entire print mechanism, but they are different. The IL printer has an optical encoder wheel on the shaft. I will probably have to disassemble part of the print mechanism and replace as needed?

[Viktor Toth]

Are you talking about those optical sensors and wheel that detect motor speed and head position?

I've seen two variants of the HP82143A mechanism; one has those optical sensors, the other doesn't. The two mechanisms do not appear to be interchangeable, either electronically or mechanically. From your description, it appears that your HP82162A is one variant, and your HP82143A is the other.

Viktor