I recently found an old sharp / Sony CD-C612 3-disc CD changer at a garage sale for $15. I took it apart, cleaned out the laser lens several times, and used a can of compressed gas to attempt to clean the dust out of the circuit boards (there was alot) I bought an RCA to 3.5 mm adapter to plug it into my computer, so I could have surround sound coming from my computer when watching movies. All that ended up working great with the exception of cleaning the laser lens. I used a CD lens cleaner from Best Buy as well as rubbing alcohol on a Qtip - multiple times. I'm starting to suspect it is not the lens that is the problem. While CDs play much better than they previously did before cleaning, they still tend to skip periodically. I even bought a bunch of brand-new CDs to ensure it wasn't on the CD end. Brand-new CDs will still periodically skip. Not very badly, but still enough that I can't generally get through a full CD without some intermittent skipping.
I'm wondering if anyone has any suggestions on what else I can do to fix this so it doesn't skip at all.
Also, the unit did not come with a remote control and I am trying to find one on Amazon but finding a remote for the exact model seems impossible. I would greatly appreciate it if anyone could point me in the right direction as far as a suitable remote control that would work for this unit because I'm really not sure which remote controls would work for it.
I'm wondering if anyone has any suggestions on what else I can do to fix this so it doesn't skip at all.
Also, the unit did not come with a remote control and I am trying to find one on Amazon but finding a remote for the exact model seems impossible. I would greatly appreciate it if anyone could point me in the right direction as far as a suitable remote control that would work for this unit because I'm really not sure which remote controls would work for it.
Hi Amazilu,
I have to ask ... why are you so convinced it is the lens? Leave it alone now, you have bugged it enough!
I have serviced CD players since they were introduced. Once you gently clean the lens surface with a Q-Tip (not a plastic shaft type!), with Methyl Hydrate, you're done with it. Clean the turntable surface and clamper as well. So called "cleaning discs" will not do anything normally. You're going to whip a soft, plastic lens at 500 rpm with a brush?? Probably not a great idea.
Next, you could measure the laser output (you have a laser power meter right?). I would go directly to looking at the RF pattern coming off the CD (a known example with clean eye pattern or a test CD). From that you can determine a lot. You would also listen carefully to the mechanism. The next step is generally to read off the head what the number is for Iop. Then you measure the laser current without blowing up the laser diode, and compare that figure to the number on the head. You are allowed 10% maximum before the head is condemned for sure. If it is up there, you probably need a new head. Also a new disc motor and then you pretty much have a new machine. Replace the belts while you're in there.
There is a lot more. One other thing - DO NOT TOUCH THE ALIGNMNET POTS !!!!
-Chris
I have to ask ... why are you so convinced it is the lens? Leave it alone now, you have bugged it enough!
I have serviced CD players since they were introduced. Once you gently clean the lens surface with a Q-Tip (not a plastic shaft type!), with Methyl Hydrate, you're done with it. Clean the turntable surface and clamper as well. So called "cleaning discs" will not do anything normally. You're going to whip a soft, plastic lens at 500 rpm with a brush?? Probably not a great idea.
Next, you could measure the laser output (you have a laser power meter right?). I would go directly to looking at the RF pattern coming off the CD (a known example with clean eye pattern or a test CD). From that you can determine a lot. You would also listen carefully to the mechanism. The next step is generally to read off the head what the number is for Iop. Then you measure the laser current without blowing up the laser diode, and compare that figure to the number on the head. You are allowed 10% maximum before the head is condemned for sure. If it is up there, you probably need a new head. Also a new disc motor and then you pretty much have a new machine. Replace the belts while you're in there.
There is a lot more. One other thing - DO NOT TOUCH THE ALIGNMNET POTS !!!!
-Chris
For many CD player there are replacement laser units. They come adjusted and just have to be installed with great care. Even better and usually not much more expensive are complete drives. We talk about ar region around 20$.
With both the details are most important. Often just tiny things differ. With lasers the connections, drives often have different axles, longer, shorter or the Puck the CD rests on with a different profile. You got to find and solve these problems.
Is your CD changer worth it? If it has a coax digital out you can use it with a better D/A converter. I have a Pioneer 100 CD changer which sounded disapointing over the build in A/D, but now performs amazingly well over the retro fitted digital out.
PS I don't talk about the many expensive CD player I got for near nothing and repaired with a rubber belt for 2 Cent.
With both the details are most important. Often just tiny things differ. With lasers the connections, drives often have different axles, longer, shorter or the Puck the CD rests on with a different profile. You got to find and solve these problems.
Is your CD changer worth it? If it has a coax digital out you can use it with a better D/A converter. I have a Pioneer 100 CD changer which sounded disapointing over the build in A/D, but now performs amazingly well over the retro fitted digital out.
PS I don't talk about the many expensive CD player I got for near nothing and repaired with a rubber belt for 2 Cent.
Actually, be very careful about cheap CD laser head replacements. Many do not have brass sleeve bearings, do not buy those! Also, most do require adjustment. There is one adjustment no one should ever touch, and that is the laser power adjustment.
The disc table height is critical. Measure very carefully and record your reading. I have brass jigs for many, but my caliper is a sanity check I always use.
As for the digital out. If you don't begin with a clean, stable eye pattern ... give up. Fix it or discard it. As far as the DSP is concerned, garbage in, garbage out. So a cheap or poorly performing transport on a great D/A is a total waste.
The disc table height is critical. Measure very carefully and record your reading. I have brass jigs for many, but my caliper is a sanity check I always use.
As for the digital out. If you don't begin with a clean, stable eye pattern ... give up. Fix it or discard it. As far as the DSP is concerned, garbage in, garbage out. So a cheap or poorly performing transport on a great D/A is a total waste.
Ok, thanks guys. So yeah, probably not the lens as anatech points out. Seems like alot of effort to fix a cheap CD player but I might give it a shot just to learn more about reparing audio gear. Also it might be my imagination but it seeems like more I play a given CD's on it the better that particular CD playes. Idk why that would be.. but what about that remote control? Can I just get any programmable remote? If not what do I need to know?
Hi Amazilu,
Alright. To repair audio equipment you need at the minimum:
CD players are mechanical as well as electronic. They have motors, bearings and mechanical alignment. So when one doesn't work, adjustment is your last option unless someone has been in there first. Then you need experience to figure that out. Everyone lies. Figure out what wears or what can change. These are complicated and some adjustments are touchy and exact. There is a big difference between it working, and working properly. I get hacked units in all the time. It is frustrating because everyone is an expert, and "fixing stuff" is easy, not requiring skill. Sure.
Remember one thing. Working techs in any field or real experts do not have time to post videos on YouTube. Also, there are a ton of steps we do without thinking, so it looks easy when we do it. It is difficult to troubleshoot without the unit in front of you because we get clues from all kinds of things.
Don't get discouraged, but learning to do it properly is involved and involves a lot of knowledge. So, go for it. But do not repair anything for anyone else or sell something you fixed until you are doing it exactly right. If it is easy, you missed a ton of stuff that you simply don't know.
-Chris
Alright. To repair audio equipment you need at the minimum:
- A functioning brain with logic.
A decent analogue oscilloscope or a real expensive digital oscilloscope. - A good digital voltmeter, 4.5 digit minimum with high accuracy. Good brands hold their calibration and cheap ones are often out ... brand new.
- Low distortion audio oscillator
- Good THD meter
- Dummy loads (8R0, 1%, non-inductive at least 50 watts), mounted on heat sinks if they are intended to be
- Variac
- A real transistor tester (Heathkit IT-18 is an excellent example)
- A decent frequency counter
- A good understanding of how the device works and what normal signals are.
CD players are mechanical as well as electronic. They have motors, bearings and mechanical alignment. So when one doesn't work, adjustment is your last option unless someone has been in there first. Then you need experience to figure that out. Everyone lies. Figure out what wears or what can change. These are complicated and some adjustments are touchy and exact. There is a big difference between it working, and working properly. I get hacked units in all the time. It is frustrating because everyone is an expert, and "fixing stuff" is easy, not requiring skill. Sure.
Remember one thing. Working techs in any field or real experts do not have time to post videos on YouTube. Also, there are a ton of steps we do without thinking, so it looks easy when we do it. It is difficult to troubleshoot without the unit in front of you because we get clues from all kinds of things.
Don't get discouraged, but learning to do it properly is involved and involves a lot of knowledge. So, go for it. But do not repair anything for anyone else or sell something you fixed until you are doing it exactly right. If it is easy, you missed a ton of stuff that you simply don't know.
-Chris