Advanced Instruments 3900, Service Manual

Page: 144 / 184

4CP427 Rev0
(4C35/3905 Service Manual)
Page 6 of 6
NOTE: Either sets of holes may be
used to center the plungers (i.e., the
two left-most holes or the two right-
most holes).
4. Position fixture (with the left-most holes
engaged into the plungers) so that the
tapered end is facing down and up
against the left-most corner of the input
cassette bay.
5. Disconnect the main harness from
the sensor board and connect fixture
(#F1120) to the sensor board.
6. Loosen screws securing the sensor flag
on the right slot cover. With the tapered
end of fixture # F1091 at the left-most
position in the input bay and the plungers
engaged in the left-most fixture holes,
adjust the sensor flag so that it is just
beyond the point where the RED LED
turns on. Secure flag screws.
7. Loosen screws securing the sensor flag
on the left slot cover.
8. Position index mechanism to the right-
most position, lift adjustment fixture from
plungers and place the right-most holes
of the fixtures over the plungers. Place
adjustment fixture in the left-most corner
of the cassette input bay and adjust the
sensor flag just beyond the point
where the GREEN LED turns on. Secure
flag screws.
9. Check that the cassette index mechanism
moves freely from side to side (manually)
and that there is no evidence of any
binding.
10. Once the deck is reinstalled into the unit,
test for proper operation and adjustment
using the “Cassette Index” test from the
test menu (see User’s Guide, Calibration
section). Reposition flags if necessary.
Instruction for Right Slot Cover:
1. Mark the location of the slot cover on the
rack shaft prior to disassembly. Mark the
location of the guide shaft in the
mounting block (N).
2. Remove the two screws (R) securing the
cassette index motor bracket, and remove
the motor.
3. Loosen the setscrews (O) that secure the
covers to the drive shaft.
4. Remove the drive shaft by pulling out
from the keyed end.
5. Remove all components attached to the
slot cover, as in step 5 of the instruction
for the left slot cover, and install on the
replacement slot cover.
6. Reverse steps 1-5 to complete the
installation.
Instruction for Slot Cover Adjustments:
NOTE: This adjustment is required
for any slot cover replacements.
Before performing the adjustments,
position deck upright on a suitable
mounting fixture with the cassette
bays facing forward.
1. The original factory-set adjustments must
be maintained in order for the cassette
drive assembly to function properly.
2. Insert a spacer (a pencil will work)
between both solenoid plungers (S) and
brackets.
3. Adjust the center-to-center distance
between the solenoid plungers as follows:
Loosen the two set screws that secure the
right slot cover to the drive shaft and
position the slot cover so that the fixture
(#F1091) alignment holes drop freely
over the solenoid plungers.