HP HP-97 User Manual

HP-97 Component-Level Maintenance
4-21. PRINTER ASSEMBLY MAINTENANCE
J-22. The maintenance procedures for the HP-97 printer assembly are
divided into two sections; printer mechanical maintenance and printer
electrical maintenance. It is very important that the mechanical portion
of the printer assembly (print head, dc motor, reed switch, head cable
connector, gears and associated parts) be repaired before the mechanical
and electrical portions are connected together and a print command is
given. Printer mechanical assembly parts replacement is accomplished
with the aid of the exploded view drawing of the assembly. (See figure 6-2).
4-23. Once the mechanical portion of the printer assembly has been repaired,
reconnect the head connector, motor leads, and reed switch leads to the
printer printed-circuit assembly and follow the electrical troubleshooting
and ad justment procedures as outlined in table 4-14,.
L-24, Printer Mechanical Maintenance
4-25. To perform printer mechanical maintenance perform the following
steps:
a. Test the out-of-paper switch as follows:
(1) Remove paper from the printer and press PRINT x. The display should
show "Error," and the printer should not attempt to print. If the
out-of-paper switch passes this test, proceed to step b; otherwise,
continue troubleshooting the problem at step (2).
(2) If the out-of-paper switch does not inhibit printing as described
above, disconnect the two red leads from the printer PCA near the
"O" (see figure 4-11) and insert a continuity tester between them.
If the tester does not light with paper out of the printer, clean or-
if necessary- replace the out-of-paper switch after disassembling
the printer using steps b and ¢ and figure 6-2.
(3) If step (2) shows the out-of-paper switch to be functioning properly,
disconnect the red and black leads to the paper advance switch from
the logic PCA (see step 6 of the HP-97 assembly removal and
replacement procedures, paragraph 3-28) and insert a continuity
tester between them. If the tester does not light (when the paper
advance switch is not pressed), replace the switch by following the
procedures given in step 12 of the procedures referenced above,
paragraph 3-28.
(4) If steps (2) and (3) show the out-of-paper switch and the paper
advance switch to be functioning properly, replace ROM 0 on the
logic PCA.
§-21

HP HP-97 Specifications

General

Brand	HP
Model	HP-97
Category	Calculator
Language	English