Install Optical Pick-up OPU1 in CDM12 Industrial (AH03)

Place the player on the bench top, lens facing down. When working with the player, be careful not to rest the module on the center hub.  Best practice is to place the unit on a jig that allows for the center hub of the turntable to be raised off the bench top. Take care not to put pressure on the motor shaft; this can cause the turntable to be pushed in. The turntable will then “bottom out” on the casing resulting in friction and the motor will not spin.

Remove the 4 Torx no. 10 screws holding the PCB.

As you carefully lift the PCB, you will see two flex-foil cables attached to the PCB. The smaller foil controls the motor and the larger one controls the sledge. While holding the flex-foil cable, take a small flat screwdriver and lift the latches on both sides of the connector. The flex-foils should remain slack. Slide each foil out of its connector. Do not pull on the foils forcefully. Set the PCB aside in a static-protected place.

With your finger, rotate the worm gear attached to the sledge motor moving it slowly up until the OPU moves about ½ inch from the starting position. (Approximately into the middle of the sledge guidance shaft.) Take care not to remove all of the lubricant from the gear.

Remove the No. 6 torx screw holding the sledge motor retaining clip. Lift the motor just enough for the worm gear to clear the idler gear. Carefully position the chip lifter tool under the idler gear and lift it off. Set the idler gear aside.

With your hand move the OP on the sledge several times to the feel how easy it moves and finally position it to the left to clear the large gearwheel. Position the chip lifter under the large gearwheel as close to the center as possible and lift the gear. It should come up directly from the shaft. (In our demonstration the gearwheel came out with the shaft attached.)

Using the T6, remove the screws holding the retaining clips, while securing the sledge guidance shaft of the OPU on both sides.

Lift the sledge guidance shaft of the OPU on both sides at the same time and slide the top sledge actuator spring out of the sledge guidance plane and remove the old OPU.

As you perform this process, familiarize yourself with the OPU. Pay close attention to the spring-loaded, toothed black bar. During removal, take care not to disengage the small wire that acts as a spring. If this happens, carefully reinstall it with tweezers. You will need to compress this bar during the installation process. (In the case of the old OPU, you do not have to worry about it, since it will be discarded.)

Remove the new OPU1 from the box. Most likely, you have received and OPU1 that looks similar to the one pictured above in Step 7. If this is the case, disregard the following steps that describe removal of the OPU from its plastic chassis — you won’t need to do this.

If you have purchased an OPU1 that is housed in a plastic chassis (labelled as CDM12.4), you will remove the OPU1 from this plastic chassis. The sledge motor worm gear has to be rotated in the opposite direction – down. This assembly is securing the sledge guidance shaft by mechanical stoppers. Use tweezers or a flat screwdriver to remove these stoppers and discard them.

To simplify the removal and prevent damage to the OPU1, cut the upper sledge guidance plane with wire cutters (see photograph) on both sides, carefully moving it away from OPU1. Remove the OPU1. Inspect the OPU1 and make sure it slides freely on the shaft. You can discard this assembly (or use it for additional spare parts). The turntable motor is compatible and can be used also. Please return to the Service page for self-service instructions for turntable motor replacement.

Since the CDM12 modules are older units, it is important to follow this next step. Inspect the module for wear and tear. With a clean low-lint cotton swab, wipe all exposed lubrication points of old grease and dirt. Discard the cotton swab. Make sure no cotton fibers remain on gears and rails. Lubricate the module according to the factory instructions found on our Service page. Use Tribol 9890 Moluballoy grease available from Enco, or substitute Krytox GLP-204 performance lubricant made by DuPont.

Install the new OPU1 into the module. Insert the actuator sledge spring into the sledge guidance plane first and than insert the shaft into both shaft slots. Reassemble the shaft holders. Tweezers work the best in this process. Touch the shaft as little as possible; it has all the needed lubrication. If you need to reapply lubricant, use a small amount.

CAUTION: This is the most critical step of the repair!

Slide the OPU1 all the way to the left to install the large gearwheel. Position the large gearwheel on the shaft, but do not push all the way down yet! You do not want to damage the black toothed bar on the OPU1. Carefully with tweezers push the toothed bar about 1/16 away from the large gearwheel. While pushing the toothed gear, push the larger gearwheel all the way down until you feel a soft snap. Do not apply excessive force! The large gearwheel cannot touch the casing of the player. Slide the OPU1 along the sledge several times to make sure it is not dragging and feels the same as in step 3.

Remove the old lubricant from the sledge motor worm gear, idler wheel and large gearwheel. Reinstall the idler wheel. Do not reverse position. See the photograph for the proper direction of installation. Add one small dot of lubricant between the pivot spring and sledge motor worm gear. Reinstall the sledge motor and secure it with the clip holder. Apply small amount of lubricant between the motor worm gear, idler wheel and large gearwheel.

Remove the ESD clip from the OPU1 flex foil cable and discard. Take the PCB and reinsert the flex foil cables into their connectors. Insert them all the way down and push the locks down on each side to secure the cables on both sides. Mount the PCB back to the player and install the 4 No. 10 torx screws.

The OPU1 replacement is now finished.

If the CDM12 module came out of a jukebox, install it into the jukebox and test it. The best way to test in a jukebox is to play the first and last track on several CDs. For hifi units, reinstall and play tracks from the number of CDs.

If your jukebox or hifi transport works, the repair process has been a success.