The motor running bwd at high speed -- in Service Mode, Position 2 -- is normal if there is NO disc. I compared it to my CD610 (very similar to CD60).
With no disc (in Service Mode), the CD610 spins bwd at high speed.
With disc (in Service Mode), the CD610 spins normally (fwd, normal speed).
With no disc (in Service Mode), the CD60 (motor spindle) spins bwd at high speed.
With disc (in Service Mode), the CD60 spins bwd at high speed.
As was suggested (by anatech???), I think turntable/driver is ok. So, maybe focus lock or photodiodes.
Didn't find any flaws in PCB traces or jumpers.
Maybe the person who suggested the optical head got misaligned was onto something. I'll try swapping the CD610 CDM4/19 with the CD60 (try once again; before, I got weird results (see page 1, post 4)!
With no disc (in Service Mode), the CD610 spins bwd at high speed.
With disc (in Service Mode), the CD610 spins normally (fwd, normal speed).
With no disc (in Service Mode), the CD60 (motor spindle) spins bwd at high speed.
With disc (in Service Mode), the CD60 spins bwd at high speed.
As was suggested (by anatech???), I think turntable/driver is ok. So, maybe focus lock or photodiodes.
Didn't find any flaws in PCB traces or jumpers.
Maybe the person who suggested the optical head got misaligned was onto something. I'll try swapping the CD610 CDM4/19 with the CD60 (try once again; before, I got weird results (see page 1, post 4)!
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Nope ....
You were wrong on all counts, chum
Got it workin' .... after hours of chasing jumpers and traces.
Wrong direction (note: not misdirection!).
Guesses -- anyone -- as to the culprit?
Go back to the beg. of this thread. You'll find the answer.
Now, how the accident caused the problem is one effin' mystery!!
I do have another problem, tho ... no sound ... working on that ...
Nope!
You were wrong on all counts, chum
Got it workin' .... after hours of chasing jumpers and traces.
Wrong direction (note: not misdirection!).
Guesses -- anyone -- as to the culprit?
Go back to the beg. of this thread. You'll find the answer.
Now, how the accident caused the problem is one effin' mystery!!
I do have another problem, tho ... no sound ... working on that ...
Laser power (current)
Culprit: Laser power (current). Adj. to about 2.5k (on pot). Disk booted immediately. (Back on page 1, i did mention this. With my smartphone to "look" at it, I noted it was dim compared to my other Philips CDPs.
Not sure how it got out of whack during the accident.
The eye pattern may off be because the laser power was changed. Maybe the focus, too.
Back to the 'scope ...
Culprit: Laser power (current). Adj. to about 2.5k (on pot). Disk booted immediately. (Back on page 1, i did mention this. With my smartphone to "look" at it, I noted it was dim compared to my other Philips CDPs.
Not sure how it got out of whack during the accident.
The eye pattern may off be because the laser power was changed. Maybe the focus, too.
Back to the 'scope ...
Pleased to hear you have it working but what about all the other symptoms you mentioned, loud buzz on audio output, mild burning smell, overheating DAC chip, three motors spinning at full speed on powering up, swing arm slamming to end stops... and the open safety resistor.
To my way of thinking there is much more going on than just a misaligned laser preset. That may be masking some other issue.
but what about all the other symptoms you mentioned, loud buzz on audio output, mild burning smell, overheating DAC chip, three motors spinning at full speed on powering up, swing arm slamming to end stops... and the open safety resistor.To my way of thinking there is much more going on than just a misaligned laser preset. That may be masking some other issue.
Not outta the woods yet ....
But ... only for a while.
From cold start (power up), the audio is clear, distortion-free .... but a minute into playing, the audio starts to get "hashy" (like static) that gets progressively louder as the music plays, till it's all hash.
The "hash" sounds like "pink noise". Like this:
YouTube-- pink noise
If I cycle power on/off very quickly, the noise is still there.
If I cycle off -- wait a min. or two -- the sound comes back clean but then slowly turns to hash in a few mins.
When the audio is almost pure hash, the eye pattern still looks as clean.
It's almost as if something -- as it gets warm -- slowly creeps to distort. Not sure what that is.
Adj. the eye pattern did bring the CDP out of "mute". For a while, music sounded clean.Pleased to hear you have it working
To my way of thinking there is much more going on than just a misaligned laser preset. That may be masking some other issue.
But ... only for a while.
From cold start (power up), the audio is clear, distortion-free .... but a minute into playing, the audio starts to get "hashy" (like static) that gets progressively louder as the music plays, till it's all hash.
The "hash" sounds like "pink noise". Like this:
YouTube-- pink noise
If I cycle power on/off very quickly, the noise is still there.
If I cycle off -- wait a min. or two -- the sound comes back clean but then slowly turns to hash in a few mins.
When the audio is almost pure hash, the eye pattern still looks as clean.
It's almost as if something -- as it gets warm -- slowly creeps to distort. Not sure what that is.
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The only 'audio' fault I have had (several times) is failure of the DRAM chip that data is clocked into and out of. Its typically an 18 pin DIP chip in early Philips based players. Something like a uPD41416 ? Might be worth monitoring the supplies to it.
All the previous faults, safety resistor OC, burning smell etc... all point to some rail issue.
All the previous faults, safety resistor OC, burning smell etc... all point to some rail issue.
I think I solved the noise issue: It was a missing 22nF Vdd bypass cap on SAA7220.
(I pulled this IC as well as TDA1541A, and few nearby passive assoc. w/these ICs, when I had the "overheat" issue at pwr-up right after accident).
Just before I re-added that 22n cap, I'd noted the SAA7220 running a bit "finger-warm". Now, a bit cooler.
Anyway ... to quote Apollo astronauts at throttle-up: "What a ride, what a ride!"
BTW:
About the eye pattern .... while I could affect it with laser-power trim-pot, I could not affect it with the Focus Offset trim-pot (in any position).
And about that laser current being waaaaaaaaaaay off after the accident, whaaaaaaa??!!!!!!!!!! Ghosts? Gremlins?
(I pulled this IC as well as TDA1541A, and few nearby passive assoc. w/these ICs, when I had the "overheat" issue at pwr-up right after accident).
Just before I re-added that 22n cap, I'd noted the SAA7220 running a bit "finger-warm". Now, a bit cooler.
Anyway ... to quote Apollo astronauts at throttle-up: "What a ride, what a ride!"
BTW:
About the eye pattern .... while I could affect it with laser-power trim-pot, I could not affect it with the Focus Offset trim-pot (in any position).
And about that laser current being waaaaaaaaaaay off after the accident, whaaaaaaa??!!!!!!!!!! Ghosts? Gremlins?
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I often found that the type of Pots they used were always a little on the loose side. Perhaps look into replacing them(?).
P.
Focus offset sounds like it could be a static DC adjustment to set up a known and defined DC condition, although the terminology can be a bit blurred between service manuals/manufacturers. Some players also have a 'tracking offset' that is also a similar static adjustment. Those adjustments have no effect on the eye pattern but do have a big effect on how the player starts and initially focuses onto the disc surface. Once locked, the servo takes over as long as it is able to overcome any mis-adjustment.
Focus bias is the critical adjustment for maximum eye pattern clarity although not all players have this adjustment.
Focus bias is the critical adjustment for maximum eye pattern clarity although not all players have this adjustment.
Listening long term, noticing some glitches.
Audio seems to drop out frequently -- sensitive to disk "imperfection".
Eye pattern looks great, except when laser hits imperfection (then you can hear the focus servo).
How does one fix this?
As I noted above, I could not get the eye pattern to change regardless position of Focus Adj. trimmer.
Audio seems to drop out frequently -- sensitive to disk "imperfection".
Eye pattern looks great, except when laser hits imperfection (then you can hear the focus servo).
How does one fix this?
As I noted above, I could not get the eye pattern to change regardless position of Focus Adj. trimmer.
Tweaking in focus adj.
The Serv. Man. has a procedure to adj. the Focus Offset trim pot:
Place (+) lead of DMM on one side of trim pot and (-) to ground.
Play a CD track, and while playing: adj. pot to 400mV +/- 40mV DC.
But I max out at about 200mV (and the CDP at this level mistracks). About 145mV is what my sweet spot seems to be.
That 400mV Serv. Man. suggestion is in many other Philips Manuals, too.
Not sure what's the deal with my CD60 ... except that ... well .... Humpty Dumpty had a great fall?!!
EDIT:
Some CDs produce a "bouncing" (up and down) eye pattern. These CDs also have an audible fuzzy distorted sound to them. Is this laser power and/or focus offset?
I have dialed in focus mostly by back-and-forth/trail-and-error method.
The Serv. Man. has a procedure to adj. the Focus Offset trim pot:
Place (+) lead of DMM on one side of trim pot and (-) to ground.
Play a CD track, and while playing: adj. pot to 400mV +/- 40mV DC.
But I max out at about 200mV (and the CDP at this level mistracks). About 145mV is what my sweet spot seems to be.
That 400mV Serv. Man. suggestion is in many other Philips Manuals, too.
Not sure what's the deal with my CD60 ... except that ... well .... Humpty Dumpty had a great fall?!!
EDIT:
Some CDs produce a "bouncing" (up and down) eye pattern. These CDs also have an audible fuzzy distorted sound to them. Is this laser power and/or focus offset?
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Hi Hollowman,
The laser power should be set to 0.080 mW using a laser power meter, usually a Leader LPM-8000 or LPM-8001 using the Philips test disc 5. Now, going from fuzzy memory, the eye pattern was about 0.6 Vp-p. I could easily be wrong here.
The reason the sound dies after some run time is that the laser might be at end of life. As the laser diode heats up, the efficiency drops and the current goes up. Soon you aren't putting out a strong beam anymore and it is as if someone turns the laser power down. Now, a drop would not do this, and it wouldn't jar the trimmer enough to cause this either. If you want to replace this part, measure the original control with the laser current down a bit and set the new control to the same resistance. Then adjust as you have.
Warning. Laser diodes can be turned up to a point, then with no warning they cease to function. It will never work again if this happens. I do hear of people replacing just the laser diode, but have never seen or heard of this working from a reliable source. If your head dies, you may as well attempt this.
-Chris
The laser power should be set to 0.080 mW using a laser power meter, usually a Leader LPM-8000 or LPM-8001 using the Philips test disc 5. Now, going from fuzzy memory, the eye pattern was about 0.6 Vp-p. I could easily be wrong here.
The reason the sound dies after some run time is that the laser might be at end of life. As the laser diode heats up, the efficiency drops and the current goes up. Soon you aren't putting out a strong beam anymore and it is as if someone turns the laser power down. Now, a drop would not do this, and it wouldn't jar the trimmer enough to cause this either. If you want to replace this part, measure the original control with the laser current down a bit and set the new control to the same resistance. Then adjust as you have.
Warning. Laser diodes can be turned up to a point, then with no warning they cease to function. It will never work again if this happens. I do hear of people replacing just the laser diode, but have never seen or heard of this working from a reliable source. If your head dies, you may as well attempt this.
-Chris
Hi Hollowman,
-Chris
Some CDs have defective pit shape and the Philips transport doesn't perform well with this defect. What you describe sounds like focus gain, and the service manual should describe a filter to be made and an oscillator level and frequency. Using a 'scope you set the gain until you have as close to a 45° line I think (X-Y mode). A suspension problem will show as a horizontal shift in that display.
-Chris
I've never heard of fuzzy audible distortion being caused by something BEFORE the DAC chip -- like the Focus Offset. Hmmm... This fuzzy distortion sounds like an "analog" problem ... like opamps or I/V overloading/clipping.
Glitchy/clickey dropouts are what I associate all sections before the DAC chip. I'm, of course, am no expert!
Glitchy/clickey dropouts are what I associate all sections before the DAC chip. I'm, of course, am no expert!
Hi Hollowman,
I don't have sound on this machine so I can't listen to your file, but you can certainly have digital distortion that can sound "fuzzy" and just plain terrible. You can also get chirps from digital errors.
The thing is, never say never when it comes to systems that aren't operating properly.
-Chris
I don't have sound on this machine so I can't listen to your file, but you can certainly have digital distortion that can sound "fuzzy" and just plain terrible. You can also get chirps from digital errors.
The thing is, never say never when it comes to systems that aren't operating properly.
-Chris
I looked at the eye pattern on my CD610 (very similar to the CD60). It looks as good (but not better) than the CD60. The same disc that produces bouncing eye pattern looks equally bouncy on both CDPs -- however, only the CD60 produces the fuzzy distortion.
As instructed by the Serv. Man., I measured the resistance at LM 11-8: between test point <11> and ground. (This is essentially, the Laser Current trimpot -- see diagram). On the CD60, I measure about 500 ohms while the CD610 measures about 600 ohms. Hence, I assume both CDPs' lasers are drawing roughly similar power -- unless something is wrong with the CD60's laser-amp transistor, etc. Correct???
As instructed by the Serv. Man., I measured the resistance at LM 11-8: between test point <11> and ground. (This is essentially, the Laser Current trimpot -- see diagram). On the CD60, I measure about 500 ohms while the CD610 measures about 600 ohms. Hence, I assume both CDPs' lasers are drawing roughly similar power -- unless something is wrong with the CD60's laser-amp transistor, etc. Correct???
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Hi Katy,
The tolerances between the components could support that guess. Only by measuring the laser output with a laser power meter would give you the real answer. Laser diodes vary a lot in their efficiency, so the test was only partially useful.
I strongly doubt there is a problem with the driver transistor as that would cause an eye pattern that bounced a lot on a good disc. You noted that both transports had similar eye patterns.
Looking at the eye pattern is a lot like taking a blood sample on a person. You can find out all kinds of things, and you have noted that both units behave similarly on the defect disc. To my mind, that eliminates the mechanism, servos or servo controllers. Your fault is probably further along the signal path. The VCO could do what you are saying. It's close, but not on frequency as my guess.
-Chris
The tolerances between the components could support that guess. Only by measuring the laser output with a laser power meter would give you the real answer. Laser diodes vary a lot in their efficiency, so the test was only partially useful.
I strongly doubt there is a problem with the driver transistor as that would cause an eye pattern that bounced a lot on a good disc. You noted that both transports had similar eye patterns.
That tends to make me believe the servos are working properly. The main issue might be VCO tuning. This one may be an adjustable inductor rather than a pot. What you have found would suggest an electronic problem rather than a mechanical issue.
Looking at the eye pattern is a lot like taking a blood sample on a person. You can find out all kinds of things, and you have noted that both units behave similarly on the defect disc. To my mind, that eliminates the mechanism, servos or servo controllers. Your fault is probably further along the signal path. The VCO could do what you are saying. It's close, but not on frequency as my guess.
-Chris
Hi,
now we arrived at an area on the pcb, where 'my special friend' C2521 is located. One of the biggest troublemaker in Phiplips/Marantz/Magnovox CDP. If there is still the axial 47µF/25V capacitor built in, it's worth to check its capacity. The blue capacitor wa changed by me so often, since it's real bad quality (found capacities down to 12µF. Check it please
now we arrived at an area on the pcb, where 'my special friend' C2521 is located. One of the biggest troublemaker in Phiplips/Marantz/Magnovox CDP. If there is still the axial 47µF/25V capacitor built in, it's worth to check its capacity. The blue capacitor wa changed by me so often, since it's real bad quality (found capacities down to 12µF. Check it please
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