1985 Sony CDP-302 Tray Problem Repair

Gary Indiana

Active Member
My latest trip to Goodwill and $4 cash resulted in acquisition of another fine piece of vintage digital audio source: Sony CDP-302 made in 1985 AD.

Here is a great link (not mine) with description of the player and a couple of good pictures.

CDP-302 is a heavy, mostly metal, fine-looking little player. When I bought it, a stuck tray seemed to be the only problem it had.

Googling around I learned that frozen tray is a common problem for this particular model. And so... here's what to do to fix it.


Topless view: very good old school, little plastic, lots of heavy metal. Proper transformer in the power supply.

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Old school little known Sony DAC CX20152 giving "pure" hospital grade vintage digital sound. Some loved it, others re-converted to vinyl because of it.

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Here she's up side down showing her inner beauty. The laser transport is state-of-the-art electro-mechanical marvel. To quote an expert from the link posted above: Disc loading and track access is faster than greased lightning on a banana peel. And that's exactly right!

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When bottom cover removed, these two round laser transport rails should be lubed with light machine oil.
Sewing Machine Oil will work perfectly well.

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And here is one of the troublemaking culprits stopping the tray from opening: the yellowish nylon pulley. It was spinning on grease that became glue after a quarter of a century of hard work. This has to be removed and cleaned up with Q-tip and rubbing alcohol.

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Metal housing removed. Careful with that tiny E-clip - they might jump like a frog while being removed. I lost mine and had to get replacement for 23 cents at Ace hardware.

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This pin was really sticky. Rubbing alcohol cleaned her up. This does not need any lubrication. The two rubber belts were still in great shape. I cleaned them up with alcohol and put them back to service. Be careful not to stain them with grease or oil: it would eat them up fast.

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There is more glue that used to be grease many years ago that needs to be removed. The round CD tray rail is best removed completely (one screw) and cleaned thoroughly with alcohol. Clean inside the holes with Q-tip dipped in fine machine oil. Lubricate the round stick with oil. Make sure oil doesn't drip. The flat housing on the other side of the tray need to be removed also (3 screws) and all goo underneath needs to be cleaned up and left clean & dry.

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The transport in CDP-302 is amazing. It sounds good, too, but there is room for improvement, and so I plan to tap to the circuit for digital out, and hook up good external DAC to it.

This would be the tapping point. However it may need some tweeking like: buffer, or inverter, or muting between tracks, or combination of them.

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This is the pin to tap.
 
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A couple of corrections:
1. Clean the old grease / oil off first with alcohol, especially the posts that the laser slides on. They must be meticulously clean. Keep moving the laser back and forth to get the alcohol in the bearings and clean them.
2. Do not use 3 in 1 oil on the laser slides. It gums up over time. I have found the best oil to use is Tri-Flow. Use the snorkel tube and gently squeeze the valve over a wastebasket so it just starts to flow, then while it is still dripping, apply 3 or 4 drops to each slider and move the laser back and forth to spread it. Use the same oil on the post that the drawer slides on, after cleaning it with alcohol.
 
I have one of these.....And really like the transport side. But the headphone out if fubar. As in it pops very loudly when you turn the volume knob. Its not the pot...but something wrong somewhere. I even have the remote for mine!
 
I have one of these.....And really like the transport side. But the headphone out if fubar. As in it pops very loudly when you turn the volume knob. Its not the pot...but something wrong somewhere. I even have the remote for mine!

I think there is a drive IC for the headphones. It's probably bad.
 
Dr*audio, thanks for the suggestions.

I mentioned 3-in-1 oil because it's easy to buy, but I use fine machine oil in needle oiler on moving parts. I did not know that 3-in-1 gums up, but I trust you on that. Sewing Machine Oil should be perfect for this application.

Now, Tri-Flow I generally avoid. It is with Teflon and Teflon causes aluminum to seize. Try it on a volume pot if you don't believe me.
 
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I have one of these.....And really like the transport side. But the headphone out if fubar. As in it pops very loudly when you turn the volume knob. Its not the pot...but something wrong somewhere. I even have the remote for mine!
Resoldering the pins of the headphone output jack can help.
 
Its deff not a solder problem. it sends dc to the headphones when you adjust the volume
It might be the amp chip gone bad then. I just tried mine with headphones and it works well.

EDIT
Last picture in my post has schematic including the headphones stage. If you have DC coming from outside, it may show on your headphones. Unplug any RCA cables you may have while listening to headphones.
 
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It might be the amp chip gone bad then. I just tried mine with headphones and it works well.

EDIT
Last picture in my post has schematic including the headphones stage. If you have DC coming from outside, it may show on your headphones. Unplug any RCA cables you may have while listening to headphones.

it does not have a DC problem unless you adjust the volume. I am pretty sure it is that IC chip.

BTW do you have the remote?
 
Dr*audio, thanks for the suggestions.

I mentioned 3-in-1 oil because it's easy to buy, but I use fine machine oil in needle oiler on moving parts. I did not know that 3-in-1 gums up, but I trust you on that.

Now, Tri-Flow I generally avoid. It is with Teflon and Teflon causes aluminum to seize. Try it on a volume pot if you don't believe me.

I am sure Teflon itself can't cause anything to seize because nothing sticks to it. There may be a solvent in Tri-Flow that caused your pot to seize. I would not use it in a pot because it is not meant to be a contact cleaner.
 
do you have the remote?
It was without the orig. remote. But any Sony CD remote should work fine for the basic functions.

I love the mechanics of this player and how super-fast it reads dics, including CDRs, so I will be working on tapping the digital for external DAC to make it a super-sounding CD machine. Will post results when/if my efforts are successful.
 
Great Thread. I have a CDP CE305. It is a 5 tray machine from the nineties and it still works!
This thread has some pointers which I can use for its maintenance. Thanks!
 
WOW! This is a great repair thread.....I have a CDP-302, I love it! I bought it new and have never regreted the $550 price tag from back in the day. Although it has not been playing CD properly, it skips a lot, will not track properly. Some newer CDs it will not even read. But even if it does begin to read the CD it will eventually skip and jump back and forth.
I am really hoping it is just the transport tray not gliding smoothly, I have opened it up before and cleaned it but never applied any of this sewing machine oil. Also the tray wheel I will clean as I did not know that is probably the issue with my tray, I have to pull it out with my finger nail.

But when it does play its sound is the best and I do like how it has played CD-R too....I have many burned CD-R and it has never had issues playing them.

Sounds like a great project for me today.....snowy Sunday so not going anywhere.

Thanks for posting this Gary Indiana!
 
Ok now I need some help. I did all the above except for these instructions ...
"There is more glue that used to be grease many years ago that needs to be removed. The round CD tray rail is best removed completely (one screw) and cleaned thoroughly with alcohol. Clean inside the holes with Q-tip dipped in fine machine oil. Lubricate the round stick with oil. Make sure oil doesn't drip. The flat housing on the other side of the tray need to be removed also (3 screws) and all goo underneath needs to be cleaned up and left clean & dry."

Because I don't understand where the one screw is or the 3 screws........Anyhow I was able to make the tray slide out much, much better now. I also turned the machine over and cleaned the wheel pole and the 2 pole glides that I think the laser assembly slides on, I added the machine oil and it seemed to slide nicely now.

But here is my dilema.
The machine plays my older CD's very well. There are some new purchase CDs that the machine will not read, it simply spins and eventually stops. If I press play it will just keep scanning and sometimes will begin track 1 but will never read it fully and it will just skip around. Occasionally it will play but eventually will just skip all over.

Is this a laser issue? Tracking issue still because I did not complete the above procedure? Since it plays some CDs perfectly fine, I assume my laser is still in good shape....what might my problem be, what else should I do or try or clean??

Thanks in advance.
 
Hi guys, Im gonna be buying one of these cdp-302 this week for $40.
The seller says it works perfectly and shows no wear.
It has also recently been lubed as well.

Heres some pics.

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Is it necessary to replace all the caps ?
 
Got one with original remote and manual. IIRC, the transport is the BU-1. Seek is as fast as you will find in a modern CDP. I've been thinking about getting an outboard DAC like the Sony DAS-703 which has variable output.
 
Had my CDP302 since '85 when I bought it new for $800Can. It was a bit flat sounding but after many mods it sounds as good as any other you'd care to mention. Basically you need to change the caps in the reconstruction filter from mylar to polystyrene. This will open up the sound. Also change the six opamps in the sample/hold and filter circuits to reduce HF distortion. The ones I ended up with were OP249s which were better than the AD712s I originally installed. There are several other mods you can make but the ones I mentioned are the most important.

Bryan
 
But here is my dilema.

The machine plays my older CD's very well. There are some new purchase CDs that the machine will not read, it simply spins and eventually stops. If I press play it will just keep scanning and sometimes will begin track 1 but will never read it fully and it will just skip around. Occasionally it will play but eventually will just skip all over.

Is this a laser issue? Tracking issue still because I did not complete the above procedure? Since it plays some CDs perfectly fine, I assume my laser is still in good shape....what might my problem be, what else should I do or try or clean??

Thanks in advance.

Besides slow degrading performance of the laser and lense (the plastic lens transparancy could degrade, notably when cleaned with the wrong products), it might be an affair of re-adjusting the focus and tracking of your pick-up assembly. The details how to do this are well explained in the service manual, but requires a good scope and some electronics know how/experience. An old fashion hifi service center should be able to do that for you, sometimes you will have to find manual yourself in advance (you can't expect them to have any manual).
 
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