HP97 The journey begins

[teenix]

Hi all,

I have the 19C fully assembled. After a bit of practice, if the board to board connector pins line up ok, then the cases come together quite easily. I had to add some code to format the new memory IC because it may have random data in it when factory fresh.

The attached image shows the printer output, which looks reasonable. It seems as though the paper is bending a little bit when the print head is near the middle of travel.

Even though the motor driver is supposed to compensate, just like the 97, the print carriage seems quite susceptible to changes in drag which alters the print line length a bit. The only way I could get the printout aligned like shown was to gently hold the paper down just above the print head. If the paper sticks up and rubs against the top of the print head, the line length changes a bit. Also, I need to gently apply a tiny bit of pressure to pull on the paper to get even line spacing, so I suspect the paper advance needs servicing.

I also noticed that if the rubber mounts for the print motor are not even, the motor sits a little bit out of alignment.

I can change the print speed and intensity values from the keyboard and the printer responds accordingly, darker, lighter, faster slower.

Unless I go back to square one, I don't think there is much more I can do with this mechanical marvel. Everything else seems to work ok. I tried writing a program that when it runs, loads new program and data files and it all seems to work.

I'm sure there will be bugs coming, but what a trip :-)

cheers

Tony