Hi Dragonmaster, hi hjelm,
I'll try the finger burning test this evening and will post results.
But thinking of the fact that sometimes the motor doesn't start spinning, I guess the problem might be a motor failure and diffuclty to keep the speed (so ticks...).
Any idea of a source of motors for CD?
Stefano
I'll try the finger burning test this evening and will post results.
But thinking of the fact that sometimes the motor doesn't start spinning, I guess the problem might be a motor failure and diffuclty to keep the speed (so ticks...).
Any idea of a source of motors for CD?
Stefano
Oh, I forgot to read
I had the SAME problem than you with my drive-swapped(What corrected the problem) Sony. If you put your finger, the drive should NOT slow down, except if there's a problem.
Try to drive the motor at the voltage marked on it to see if you can slow it down with your fingers before changing it,
then try putting a fresh pickup if it works fine, it always help and you'll have one more in case of problems.
If changing motor and pickup don't work, then there's a controller problem. The over-voltage might have damaged it.
I had the SAME problem than you with my drive-swapped(What corrected the problem) Sony. If you put your finger, the drive should NOT slow down, except if there's a problem.
Try to drive the motor at the voltage marked on it to see if you can slow it down with your fingers before changing it,
then try putting a fresh pickup if it works fine, it always help and you'll have one more in case of problems.
If changing motor and pickup don't work, then there's a controller problem. The over-voltage might have damaged it.
Ciao DragonMaster, Hjelm,
yesterday evening I looked for photos of variuos CD transports and pickups and recognized in a Roksan Caspian M Series-1 the very same transport mechanism, made by Sanyo (I couldn't recover info on the Audiomeca one, but by self-exam).
Thanks for the input DragonMaster, so I fear the problem seems motor related, rather than controller. I tried your test and controller doesn't start burning all of a sudden, but after 30 secs, I could keep on touching the heatsink.
I found a site with Sanyo spares unit but, I still miss the part numbers... should you have any link... thanks a lot again,
Stefano
yesterday evening I looked for photos of variuos CD transports and pickups and recognized in a Roksan Caspian M Series-1 the very same transport mechanism, made by Sanyo (I couldn't recover info on the Audiomeca one, but by self-exam).
Thanks for the input DragonMaster, so I fear the problem seems motor related, rather than controller. I tried your test and controller doesn't start burning all of a sudden, but after 30 secs, I could keep on touching the heatsink.
I found a site with Sanyo spares unit but, I still miss the part numbers... should you have any link... thanks a lot again,
Stefano
C.D. motor running slow.
Stefano, I have repaired a lot of players with a similar problem. I would bet the motor has shorts in the commutator. An easy way to check it: disconnect from the drive circuit, put a 10 ohm resistor in series with it connected to a battery. (1.5 volt) Put your o-scope across the resistor and watch the voltage as the motor spins. It should be quite constant. If you see a sawtooth or spike waveform, then I would replace the motor. If it will not spin on a battery, it is bad for sure.
A cheat: sometimes you can give the motor a quick blast (less than 3 seconds) with a 12 volt supply and clear the short for a little while. Limit the current so you do not burn the motor if it has a bad short. Good luck with it. Regards, Steve
Stefano, I have repaired a lot of players with a similar problem. I would bet the motor has shorts in the commutator. An easy way to check it: disconnect from the drive circuit, put a 10 ohm resistor in series with it connected to a battery. (1.5 volt) Put your o-scope across the resistor and watch the voltage as the motor spins. It should be quite constant. If you see a sawtooth or spike waveform, then I would replace the motor. If it will not spin on a battery, it is bad for sure.
A cheat: sometimes you can give the motor a quick blast (less than 3 seconds) with a 12 volt supply and clear the short for a little while. Limit the current so you do not burn the motor if it has a bad short. Good luck with it. Regards, Steve
Hi Steve and all,
thanks a lot for your really great advice and me-proof step guide . I plan to do some test this weekend!
Besides, I hope that while disconnecting the motor to check its integrity, I'll be able to find a part ID number, which could let me identify a possible substitute for motor.
I guess there are many different models. Is there any particular brand correspondence or, rather, motor models (and features) better than others???
I'll look for some info on the web, I'll share should I get anything
Have a nice day,
Stefano
thanks a lot for your really great advice and me-proof step guide
. I plan to do some test this weekend!Besides, I hope that while disconnecting the motor to check its integrity, I'll be able to find a part ID number, which could let me identify a possible substitute for motor.
I guess there are many different models. Is there any particular brand correspondence or, rather, motor models (and features) better than others???
I'll look for some info on the web, I'll share should I get anything
Have a nice day,
Stefano
Sometimes there's a sticker under the motor, sometimes on the sides.
BTW, could you write us (and search if you didn't) the drive assy. number?
And for the pickup, I think you wrote the serial number instead of the model no . . .
Can I put a cheapo PC speaker instead(I'll try the dead drive motor in my Sony)?
Cheapo p.c. speaker.
I have never tried that approach. I have an old (built in jr. high) heathkit transistor tester. It has a simple ammeter on the front and two c cell batteries in it. I hook it to the motor and watch the meter as the motor spins up. If the needle jumps about every third rev and never moves below 5 (scale 1 to 10) It is a bad motor. I assume you could hear the pulses through a speaker.
Another test is watching the "eye pattern" of the unit in question. If it bounces in and out horizontally, this is also an indication of unstable speed.
This problem first becomes noticable at the outer tracks of the c.d. Less flywheel effect at slower speeds.
You may also notice a "stutter" in the audio that becomes more pronounced as the tracks are further out. This will be in time with the eye pattern bounce. Regards, Steve
I have never tried that approach. I have an old (built in jr. high) heathkit transistor tester. It has a simple ammeter on the front and two c cell batteries in it. I hook it to the motor and watch the meter as the motor spins up. If the needle jumps about every third rev and never moves below 5 (scale 1 to 10) It is a bad motor. I assume you could hear the pulses through a speaker.
Another test is watching the "eye pattern" of the unit in question. If it bounces in and out horizontally, this is also an indication of unstable speed.
This problem first becomes noticable at the outer tracks of the c.d. Less flywheel effect at slower speeds.
You may also notice a "stutter" in the audio that becomes more pronounced as the tracks are further out. This will be in time with the eye pattern bounce. Regards, Steve
Ciao all,
Steve yours description of effects related to shorted motor collimates at 99% with those I get.
Problems increases as tracks go on, i.e. when the speed decrease (less flywheel effect).
This weekend I had no time to test the motor, I plan to do this during the week and, DragonMaster, I will try to report any printed info I'll be able to recover
Meanwhile thank you all!
Ciao,
stefano
Steve yours description of effects related to shorted motor collimates at 99% with those I get.
Problems increases as tracks go on, i.e. when the speed decrease (less flywheel effect).
This weekend I had no time to test the motor, I plan to do this during the week and, DragonMaster, I will try to report any printed info I'll be able to recover
Meanwhile thank you all!
Ciao,
stefano
http://www.mainelectronics.com/motors.htm
In their CDP motors cat. there are no RPM and voltage marked, seems it's standard. All you need is shaft size.
In their CDP motors cat. there are no RPM and voltage marked, seems it's standard. All you need is shaft size.
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