CyberDrive 361D 36x IDE CD-ROM

[Rainbow]

Another CD-ROM experiment. This time it's CyberDrive 361D IDE 36x drive which reads CDs but slowly - never speeds up to full speed. The signal quality is probably not good enough for the controller to increase the speed.

There are 16 SMD caps - all 100uF/16V (and also two tiny 3.3uF on audio output - haven't touched these). They all showed ESR of 3ohms which is too much. Smell of rotten fish came out when I removed the first one - a good sign of bad caps
After replacing all 16 (replacement caps show 1ohm ESR which is OK), it reads CDs at full speed

[PeteS in CA]

Re: CyberDrive 361D 36x IDE CD-ROM

That rotten fish smell is so delightful. We got some samples from Jianghai that my boss could smell before he opened the shipping box. They didn't do very well in my tests, and the smell when they vented would gag a maggot at 50 paces.

[linuxguru]

Re: CyberDrive 361D 36x IDE CD-ROM

Long bump up - I just took apart a Compaq-branded DRD-8120B IDE DVD drive, and it has a PCB that is chock-full of similar SMT caps. The problem is that the tray will not eject with the cover on (the tray motor activates correctly, but lacks sufficient torque to disengage the main magnetic spindle clutch that grips the CD/DVD). When the cover is removed (the magnetic spindle clutch is not engaged), the motor has sufficient torque to fully extend the tray as well as retract it under the control of the eject button.

I suspect that the power supply bypass caps near the motor drive circuit have dried out and gone high ESR, thus limiting the surge current drawn by the tray motor - thus limiting the torque/force that it can deliver to the tray to disengage from the magnetic clutch.

Does this diagnosis sound reasonable?

[linuxguru]

Re: CyberDrive 361D 36x IDE CD-ROM

OK, I found a simple fix for the magnetic clutch - I stuck a thin steel washer into the upper, plastic hub that holds the magnet and engages with the spindle boss to clutch the CD/DVD in place. The washer shorts the magnetic flux and substantially weakens the magnetic attraction to the spindle - thus easing the torque requirement for the tray motor to disengage the spindle from the hub. The tray now ejects and retracts easily.

The tradeoff is that CDs and DVDs are not held by the clutch as firmly as before, and may slip when the spindle spins at higher speeds - I'll check if that's a problem later, but it seems that I can live with it, since this is only a DVD reader.

[linuxguru]

Re: CyberDrive 361D 36x IDE CD-ROM

This pic shows the mod: the washer is placed in the black plastic hub that's suspended from the upper metal lid of the CDROM drive case.

[PCBONEZ]

Re: CyberDrive 361D 36x IDE CD-ROM

Clever.
Nice job!

[shadow]

Re: CyberDrive 361D 36x IDE CD-ROM

Yes quite a clever workaround!

[Scenic]

Re: CyberDrive 361D 36x IDE CD-ROM

i just used to replace the belt for the tray

common problem on AOpen drives... tray would only open if you push the eject button and hit the drive on top.. lol

BTW: i may try to replace all those tiny caps in my set top box DVD player.
haven't used it for about a year... now it doesn't read DVDs anymore (even originals).
spins up and down all the time till it finally says "no disk"
and it got _very_ picky about (S)VCDs...

its a Cyberhome CH-DVD 402 (those thingys use a modified Cyberdrive IDE DVD-ROM.. propritary chips on the PCB unfortunately.. so replacing the drive is a no-go..)

[linuxguru]

Re: CyberDrive 361D 36x IDE CD-ROM

>i just used to replace the belt for the tray

That could also be a problem - the inner surfaces of the belt looked polished, while the outer surface was rough black. I should probably have flipped the belt so that the rough side was in contact with the pulley surface.

[PCBONEZ]

Re: CyberDrive 361D 36x IDE CD-ROM

When those get smooth take one of those tooth brush style SS wire brushes and rough up the surface.
- Don't get too crazy. Just want to scratch up the surface.
The scratches are kind like adding tread to smooth tires.
Extends the life quite a bit.

[bgavin]

Re: CyberDrive 361D 36x IDE CD-ROM

The brush sounds like a good idea.

The issue I have with all the above is the time required.
It is cheaper for me to install a new drive and be done with it.
The alternative is attempting repair or salvage at my labor rate, only to have it not work at all, or fail shortly thereafter.

[linuxguru]

Re: CyberDrive 361D 36x IDE CD-ROM

It's normally not worth the trouble to fix a CD/DVD drive. But if it's a minor mechanical issue in an otherwise good drive, which can be fixed by a small workaround for few years, then it might be worth it. The washer and belt tricks are such examples, both of which cost about a penny and ~10 mins. of work. Depending on the cost of your time, it might not be worth it.

[Agent24]

Re: CyberDrive 361D 36x IDE CD-ROM

Long bump up - I just took apart a Compaq-branded DRD-8120B IDE DVD drive, and it has a PCB that is chock-full of similar SMT caps. The problem is that the tray will not eject with the cover on (the tray motor activates correctly, but lacks sufficient torque to disengage the main magnetic spindle clutch that grips the CD/DVD). When the cover is removed (the magnetic spindle clutch is not engaged), the motor has sufficient torque to fully extend the tray as well as retract it under the control of the eject button.

I suspect that the power supply bypass caps near the motor drive circuit have dried out and gone high ESR, thus limiting the surge current drawn by the tray motor - thus limiting the torque/force that it can deliver to the tray to disengage from the magnetic clutch.

Does this diagnosis sound reasonable?

I've got a lot of Cyberdrive CD writers and more, this problem has happened to all of them

It's a simple fix - the drivebelt which links the tray motor to the tray mechanics has gone slack and starts slipping when it has to try opening the tray against the pull of the magnet on the plastic hub.

I'm in NZ, and I ordered my replacement belts from tradetech.co.nz