Trying to repair an old Onkyo DX-1500

[acid_k2]

Hi to all
One of my friends gave me (for free....) an Onkyo DX-1500, a 18 years old cd player. This beast doesn't play cds any more.
When it loads a cd, the lens of the laser laser pickup (KSS 152A) goes up and down a couple of time, then the laser turn off and cd player seems to go into "locked" or "no cd" state.
During this time, cd doesn't run (spindle motor is off). Sometimes cd starts to move for only a few degrees of rotation, then stop immediately and cd player goes into "locked" or "no cd" state.
It seems to be a common fault on old Onkyo cd player , as you can find in other threads in diyAudio forum. This time, unluckly, I have no solution to the problem, so I'll try to explain what I have done:

1st step
-cleaned: laser lens
-results: nothing

2nd step
-verified: spindle motor (run normally in clockwise and anticlockwise direction, absorbing something like 0.7A max @ 5V, with cd inserted)
-changed with a new one: spindle motor driver, LA6500 (op-amp 1A, 30V) labelled Q108.
-results: nothing

3th step
-added: 1nF capacitor (between positive and negative) on the spindle motor.
-results: nothing

4th step
-added: 100nF capacitor on the spindle motor.
-results: nothing

5th step
-verified: light emission of laser
-tried: slightly trimmed the laser current for obtain a slightly more power
-results: nothing; re-trimmed laser current to original value...

note:
-I have no schematic, anyone has it? for free? thanks!
-spindle motor driver (LA6500) has no heat-sink and get warm (at idle too). Supply voltage between Vcc and Vee is 28-29V, near the maximum ratings (from Sanyo datasheet).
- the LA6500 seems to be directly controlled by a smd CXA1082A (sony), anybody know if it is a faulty device?
-voltage regulator 78M05, labelled Q901, has a small heat-sink and become very hot (burned fingers, do you know?). Changed with a more robust 7805CV, with a larger heat-sink, with no results.
- (SK) STA341M, labelled Q107, become also very hot, but what is it? Black module with 8 in-line pins, no heat-sink...


And so, someone could give me an idea of what is happening inside this cd player? What's is wrong?
This is my real last attempt, before getting it away...
Could you help me to save this piece of history from the dump?

[sgrossklass]

Might be a tracking / focus or pickup problem. Drop me a pm if you'd like the service docs...

[vasiltech]

acid_k2, i have manual for DX-1500
where your mail?

[acid_k2]

Thanks for the help, guys!

[acid_k2]

After a loooong search, I've found a bad joint solder on the CXA1082A.

now it sounds good, except for some skipping track.... I'm trying to solve this problem too....

[acid_k2]

Yes, I'm back

and yes, this little spindle motor IS the problem...

I have desoldered it, took apart, opened , cleaned the contacts and brushes, cleaned dirt and re-oiled bushes, re-closed, tested for half an hour, and re-mounted...

No more skipping tracks, cds sound perfectly.

I have some photos, but no time to post it... maybe tomorrow...

[mlloyd1]

glad it's working now ...
but ...
i hope you don't soon regret just replacing the spindle motor completely since you had the machine open


mlloyd1

Originally posted by acid_k2
... and yes, this little spindle motor IS the problem... ...

[Jan Dupont]

Interesting....
I have some of the same problems with a DX-703
I was told that the motor was the problem, so I'm looking forward to see your pics

[acid_k2]

Originally posted by mlloyd1

i hope you don't soon regret just replacing the spindle motor completely since you had the machine open


mlloyd1

the motor is very hard to find here... i've tried to order that, but I have to wait to much time...
Mine was an attempt, it works, and I'm happy...

[acid_k2]

Originally posted by ACD

I was told that the motor was the problem, so I'm looking forward to see your pics

hi ACD
I know your cdplayer have a similar problem.
First of all, as suggestested by mlloyd1, try to find a brand new motor...



Don't try this at home!