5103 Forms Feed Stepper Motor/Emitter Timing; Adjustment - IBM 5100 Maintenance Information Manual

5103 FORMS FEED STEPPER MOTOR/EMITTER
TIMING
Adjustment
Two techniques are available for the adjustment of the
emitter timing: the general logic probe method and a
program that must be entered manually. The logic probe
method provides sufficient accuracy for normal printer
applications, but, print/ plot applications that require
reverse forms motion may need to use the programming
technique.
General Logic Probe (GLP) Adjustment Method
1.
2.
3.
4.
3-108
Power down.
Remove the printer cover. Refer to the 5103 MIM
(310).
Connect a jumper wire between test points FMA
and G7 • (forms motor driver A to ground).
a. Move the black wire from TPB2-6C to
TPB2-3C. Refer to the 5103 MIM (300).
b. Move the red wire from TPB2-5B to TPB2-6C.
Loosen the photocell assembly (two screws
II
behind the motor) so that the assembly will slide
but not move by itself.
5. Connect the probe power lead (red) to test point
V5 and the black lead to G6.
6. Place the Printer Adapter card in the service
position on machines with EC 579623 or EC
579920. Refer to the 5103 MIM (312).
7. Probe A2-U07 on the B1 board with the probe
ground lead on P08. On
machine~
without EC
579623 or EC 579920, probe TPA on the forms
feed emitter amplifier card. with the probe
ground lead on test point G8.
8. Power up.
9.
Slide the photocell down as far as possible.
10. Slowly slide the assembly up until the probe UP
light comes on.
Note: If the UP light is on with the photocell down
as far as possible, slide the assembly up until the
UP light goes out and then comes back on.
a. Hold the photocell assembly firmly in place and
tighten the two screws.
b. Verify the adjustment as follows:
- Apply a small amount of forward force on
the platen knob. The probe should stay at
the up level when you remove your hand
from the knob.
- Apply a small amount of backward force on
the platen knob. The probe should stay at a
down level when you remove your hand from
the knob.
c. Readjust if necessary.
d. Power down.
e. Move the red wire from TPB2-6C back to
TPB2-5B. Refer to the 5103 MIM (300).
f. Move the black wire from TPB2-3C back to
TPB2-6C.
TPB
0
TPAO
Right End
VieVli
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