Denon UD-M50

Hi Norman and Richard

I'm particularly interested in whether either of you have found solution in terms of alignment with the CD trays of the M50 unit.

I'm in the same boat in that the mechanism is out of sync after 2 CD were accidently placed in the same tray.

When reassembling the trays I'm guessing right that in the front of th mech tray 1 is placed above tray 2 and tray 3 resides in the lowere reading position?

Does the service manual show or describe how the cogs and trays ar positioned for assembly, if you still have a copy of the manual I woul be very grateful if you could email me a copy.

Many thanks!

Simo

I have a set of alignment diagrams for this deck. It's dead easy once you know how. It's actually a Sanyo manufactured mech. Before reassembling, ie putting any trays into the drawer, rotate the whole side gear assembly ( both sides will turn because of the coupling rod across the drawer ) several turns in both directions, and make sure that this action is completely smooth. It is quite common for one of the planet gears inside one of the large gears, to break. This then results in the gears sticking part the way round.

If you look down on the two ' windows ' on either side of the drawer topside, you will see the tops of the four gears. If you then rotate the gears, you will see a line come around. These lines MUST be EXACTLY aligned side to side ( done by disconnecting the coupling rod, repositioning one side as required, then reconnecting the rod ), and also front to back on each side, so all four lines MUST be exactly on top at the same time. This is the starting point. The drawer is then turned upside down, and tray 2 is dropped in at the back with the first tooth located over the lower ' catcher pip ' on the large gear. This position is important. It's also important to check those teeth on the tray VERY carefully for damage.

Now turn the little bevel gear ( assuming that you haven't lost it !! ) to the right, gently. The tray will start to be drawn in. Keep your left hand under it as you wind it in. When it gets to the front, and the lifting action starts, help it with your left hand fingers pressing up from below. When it has gone all the way up, stop. Now position tray 1 the same as you did for tray 2, and wind it in the same way. When it reaches the end, tray 2 should start to retreat, if you keep winding. Rocking back and forth around this point will give you a good ' feel ' for whether you've got it right.

Now push the white pin on the left underside, towards the front to lift the disc clamp. Put tray 3 in the back, and let the clamp back down again.

Now slide the gear down the rod on the right side, until it's about half way down. Now, with the bevel gear in place on the drawer, offer the right side of the drawer into its groove in the chassis, such that the bevel gear meshes with the shaft gear, and the claw on the drawer locates over the shaft. Hinge the drawer down until the left side is resting on top of its groove. Now, using something very flat like a scalpel blade, push in the flat white plastic lever which is in the way of the left side going down. If you're pressing down gently on the left side as you do this, you'll feel when it gets out of the way. Now withdraw the scalpel, and press down firmly. The drawer will snap into place with an alarming " crack " ( but don't be alarmed ... ) And that's it really. It should just work first time. This mech is also fitted in a Philips model and a Grundig and of course a Sanyo. I've also seen it, with a different deck fitted, in a DVD player, but I can't remember what make.

If you need the actual diagrams, mail me direct, and I'll pdf them for you.

Hope this helps

Geoff

"simona2001" wrote in message news: snipped-for-privacy@news.homeimprovementbanter.com...

Thanks for replying Geoff.

I have followed your instructions but when I reassemble the loading mech and power on and select a tray to open, tray 1 slides back and I can hear the motors trying to turn but the mechanism jams and ejects tray 2, I've never seen the mechanism raise tray 3.

If you could send me a copy of the diagrams I would be very grateful, I can't see a way of mailing you direct on these forums?

Simon.

Hi Norman

I have the Denon UD M50. Not having the cd changer problem, but am having a laser problem - it skips for no apparent reason. Have tried various CDs, cleaned them all thoroughly, but it still happens. Just wondered if the repair manual would help. Do you have a link where I could get a copy of the repair manual? Thanks!!

Dave Marshall

Guys i have just repaired my first Denon m50 ,(thanks to norman ibbotson for emailing me his worksheets)

if you listen you can blasting away in the back ground. my first attempt failed miserably. 2nd time i was away, where i scored was, before i inserted the first tray after aligned the dots, i check the back end for the marking on the gears (all four)

reassembled as per manual. when assembled, if you then look on the top you can see the small driving wheel i then proceed to turn this wheel (i think it was clockwise, if the tray moves to the play position then its right) and watch the mechanism work i keep going though a full cycle to ensure the was no jam. i carried on to tray one is in its position ie ready to eject. final check the markings on the gears are correctly aligned. reassembly.

great the tray work perfect, but the cd won't read the disc's, disassemble check movement of lens, great reassmble, still the same, i removed the tray clamp assembly so you can see the laser lens. get a good clean brush (i used a camera lens brush) and gave the lens and the surrounding sensors a good going over, result one happy bunny.

so dave i would suggest you manually cleans the lens, but do not touch the lens with your fingers or use solvents, it can leave grease smears, a clean stiff clean brush is best.

Yes keep your fingers and solvents off but do not use a "stiff brush". The lens mounting is very sensitive and flexible. It would be easy to damage the linkages that support it if too much force is used. At the shop where I worked we used a Q Tip, medical grade-wood handle, and with clean fingers pulled the cotton tip part way off the stick. This gave a soft but still firm without being hard end. Gently scrub/wipe the lens in a circular motion. When it's clean you can see a really nice reflection across the surface of the lens. You might also try blowing the lens assy with a dusting can, again gently. This will knock out or dislodge any "big dust bunnies" that might be in the linkage area. Most PS2's that boot but won't read disks can be fixed with a good lens and drive sled cleaning. Good luck

Hi

I have a udm50 with draw problems. Is it possible for to send me the alignment diagrams?

Thanks

Peter

I don't have the service manual electronically, but what is the actual prob lem? I usually have more "fun" getting to the mechanism than repairing it. Most drawer problems are slipping belts. You should be able to replace t he belt without losing the alignment. I will check for a procedure for you in the meantime.

Dan