HP-19C Printer

[Jonas Sandstedt]

Sounds tricky, Tony.

The HP-97 service manual states:
"Check pin 17 of the board for the FWD signal. If not present, replace U5 and U4 in
order until the 1.5 millisecond signal appears. Then go to step 10."

An illustration of the FWD waveform is shown in Figure 4-15, section 4-27.

In Appendix D, Service notes in the service manual, it is stated:

10. Doesn't print - Problem part: PICK.

So, it seems as if your suspicions are correct. I do not know if it helps, but in the HP Journal linked below, the HP-97 printer is described.

https://www.hpl.hp.com/hpjournal/pdfs/Is...976-11.pdf

Best of luck!

Jonas