cd laser replacement info needed

[ocaukrell]

Have a luxman dz-03 that has a dieing laser, I can get the part ok, (kss152a) but are there any tricks or traps I should know about when replacing it ?
Will it need any form of alignment ?
Etc ?

[rabbitz]

Should only have to desolder the anti-static solder blob and fit it and away you go. Just have to watch out for static so be careful.

[ocaukrell]

Mkay, thats what I thought, thanks for that, have a good week.

[anatech]

You may need to align it. E-F balance especially. Touch up Focus Offset. The gains should be close, you don't want to mess with those.

How's your disc motor?

-Chris

[ocaukrell]

All else seems fine, other than a dead draw belt.

how would I do the E-F and focus ?

Have old bwd dual trace 50mg cro, fluke 77, few other simple bits.
Just ordered the replacement laser (kss152a is now a toph7833), should have it tomorrow.

Any other faults I should be pre-fixing in this model ?

Thanks..

[anatech]

Hi ocaukrell,
E-F balance is a pain, you need the manual ... or Pierre Verrany test discs. Your 'scope would work fine but you need to know how to set it up.

The disc motor bearings are normally worn by now. Th edisc table hieght is critical. Measure it to the nearest mm before touching anything. From the mechanism base to the top of the table.

Do you have any service info for this unit? If you aren't familiar with doing this, you can try to stick the head in, but if you know a good tech (on CD's, not TV's !!!) he can touch it up for you.

-Chris

[ocaukrell]

Have zero info, service job, cust loves this unit so I said i'd try.
first time i've replaced a laser.
If it appears to work ok after the replacement, how critical is it to do the align ?
Disc table hight, is this from bottom of laser assembly to top of the assembly that holds the laser assembly etc ?

[anatech]

Hi ocaukrell,
Disc table height is measured from the metal sub chassis where the guide rails and motor are mounted, to the top of the disc table.

Alignment is very important. When the unit is aligned properly the sound quality is much improved, as is tracking ability.

Did you clean and relubricate the guides for the head. KSS-152A was plastic with no bearings I think. Failure to lubricate will wear out any guide, but plastic will go really fast.

-Chris

[ocaukrell]

Ok so the pic shows the table hight, correct ?
As per photo, haven't touched it yet (yuch).
Yes will be cleaning and greasing before new one goes in.
If it makes a difference to sound, could I do small (tiny) adjustments by ear ???
Yes, I know not the best but still.

[anatech]

Hi ocaukrell,
Yes, that is the correct measurement.

No, there is no way you can align anything by ear alone. Once you have experience you can listen to the servo noise, and watch the 'scope.

From the looks of that, it will need a really good cleaning. Simple transport though.

-Chris