Hi zyrobs,
I'm not trying to be harsh at all here .. but. If you don't have an oscilloscope you have no business poking around in a CD player. Or most other things for that matter. An oscilloscope and good DVM are minimal requirements for working on anything for that matter.
May as well pack it up. You're flying blind with zero idea of what is really happening. Sorry. It's like working on an engine with only screwdrivers, no wrenches.
I'm not trying to be harsh at all here .. but. If you don't have an oscilloscope you have no business poking around in a CD player. Or most other things for that matter. An oscilloscope and good DVM are minimal requirements for working on anything for that matter.
May as well pack it up. You're flying blind with zero idea of what is really happening. Sorry. It's like working on an engine with only screwdrivers, no wrenches.
Hi zyrobs,
Can you borrow one, or take the unit to someone who has one that can help you?
Otherwise pack it up. Take it to a tech. If you can't afford to fix it now, save up and do it later. The equipment, physics or troubleshooting doesn't care if you can afford something or not. You either need it, or you don't. You do. It's like wishing gravity doesn't apply to you as you fall just because you don't want it to. Sometimes you simply can't do a job without all the things you need.
I would rather have you (or someone) repair it so it works than it being damaged beyond repair because someone tried to do something they couldn't do. Messing around and changing things without good reason will most likely cause more damage than leaving it alone. I'm trying to give you the most helpful advice I can, and I know it isn't what you want to hear.
Can you borrow one, or take the unit to someone who has one that can help you?
Otherwise pack it up. Take it to a tech. If you can't afford to fix it now, save up and do it later. The equipment, physics or troubleshooting doesn't care if you can afford something or not. You either need it, or you don't. You do. It's like wishing gravity doesn't apply to you as you fall just because you don't want it to. Sometimes you simply can't do a job without all the things you need.
I would rather have you (or someone) repair it so it works than it being damaged beyond repair because someone tried to do something they couldn't do. Messing around and changing things without good reason will most likely cause more damage than leaving it alone. I'm trying to give you the most helpful advice I can, and I know it isn't what you want to hear.
Again, you are not telling me anything I don't know. Please understand that I'm repairing this as a hobby project. The worst case scenario is that I end up with a player that does not work, as opposed to a player that currently does not work.
Besides the point is moot because I got it working thanks to lcsaszar who consulted with me in private messages.
I resoldered (completely removed, then put back) the problematic SAA7010 and switched the two parts marked as 22n (what are they? non-polarized capacitors?) near the SAA7010. The player has now been playing without a problem for a good 30 minutes, and it has perfect sound on both channels. So the fault was indeed somewhere around the SAA7010, though I don't know if what helped it was fixing the solder around the 7010 or if it is the 22n parts which are faulty. The soldering looked right on the 7010 too so I don't know if it was that which helped.
Also reflown four griplets around that part of the board and made sure they have continuity, but I suspect they were already fine before.
With that the only remaining faults are minor:
And while I'm at it I'll also see if I can modify the player so it has its own RCA sockets.
Besides the point is moot because I got it working thanks to lcsaszar who consulted with me in private messages.
I resoldered (completely removed, then put back) the problematic SAA7010 and switched the two parts marked as 22n (what are they? non-polarized capacitors?) near the SAA7010. The player has now been playing without a problem for a good 30 minutes, and it has perfect sound on both channels. So the fault was indeed somewhere around the SAA7010, though I don't know if what helped it was fixing the solder around the 7010 or if it is the 22n parts which are faulty. The soldering looked right on the 7010 too so I don't know if it was that which helped.
Also reflown four griplets around that part of the board and made sure they have continuity, but I suspect they were already fine before.
With that the only remaining faults are minor:
- when ejecting a disc, the motor keeps going even after the tray is fully out. I have not looked into this at all yet.
- will need to identify and replace those 22n parts (capacitors?) or at least test if they are indeed faulty or not. just in case...
- the top cover is missing its screws, the manual clearly marks them as N4x6.5mm and 2.9mm diameter screws fit properly so this will be easy. alas I don't have any black screws.
And while I'm at it I'll also see if I can modify the player so it has its own RCA sockets.
Hi zyrobs,
I'm very happy you have it running. Just as easily you may have damaged it further. Anyway, the end result is excellent. Soldering the griplets is probably what fixed it in my experience. This is the #1 thing I always tell other techs to do.
The 22n capacitors are non-polarized film types.
There are limit switches, one is either broken, not being actuated or has bad contacts. This is your tray issue most likely. If the player runs, they are probably fine. They do not fail very often.
If you have something working well, stop. Don't mess with it further. Sure, you can install chassis mounted RCA jacks. I can see why you'd want to do that.
I'm very happy you have it running. Just as easily you may have damaged it further. Anyway, the end result is excellent. Soldering the griplets is probably what fixed it in my experience. This is the #1 thing I always tell other techs to do.
The 22n capacitors are non-polarized film types.
There are limit switches, one is either broken, not being actuated or has bad contacts. This is your tray issue most likely. If the player runs, they are probably fine. They do not fail very often.
If you have something working well, stop. Don't mess with it further. Sure, you can install chassis mounted RCA jacks. I can see why you'd want to do that.
I don't quiet understand the griplets since I only removed the solder from their top and bottom, I didn't manage to get it out from inside the vias. But maybe just working on them was enough to reform the solder inside. Either way, I'll add some single strand wire to their insides, as it is recommended in some online repair guides.
The tray thing is odd, I had it running for ~2 hours now and it only rarely keeps the motor running on eject. To clarify, what it does (did) on eject is running the motor for an extra 2-3 seconds then stopping it. But after operating it for so long, it either runs the motor for an extra 1 second or not at all once the tray it out.
Thanks for identifying those capacitors. I only had to work with polarized and tantalum types before.
Damaging the unit is a risk with every DIY-type repair. I have close to 30 CD players of various types (game consoles, PC drives, a Laserdisc player), many which I had to repair myself, and yes, a few which I broke. Working on them and fixing them up is a lot more fun than just using them as players. So I think I'll keep working on this a bit more. I mean I already recapped the entire thing, I may as well "tune it up" a bit more.
At the very least I'll fix all the griplets on both boards and get a new tray belt, and see if I can add the RCA jacks.
The tray thing is odd, I had it running for ~2 hours now and it only rarely keeps the motor running on eject. To clarify, what it does (did) on eject is running the motor for an extra 2-3 seconds then stopping it. But after operating it for so long, it either runs the motor for an extra 1 second or not at all once the tray it out.
Thanks for identifying those capacitors. I only had to work with polarized and tantalum types before.
Damaging the unit is a risk with every DIY-type repair. I have close to 30 CD players of various types (game consoles, PC drives, a Laserdisc player), many which I had to repair myself, and yes, a few which I broke. Working on them and fixing them up is a lot more fun than just using them as players. So I think I'll keep working on this a bit more. I mean I already recapped the entire thing, I may as well "tune it up" a bit more.
At the very least I'll fix all the griplets on both boards and get a new tray belt, and see if I can add the RCA jacks.
I think the switch is intermittent, just use is cleaning the contacts, but use some contact cleaner.
Repairing the griplets is properly done by removing the solder, adding liquid solder flux, then using fresh solder. You don't need to apply excessive solder. Also any component leads used for top to bottom connections (there are a few).
Try to approach each repair as if it is for someone you care about. You'll learn more and have something you can be proud of. Remember that just because something works, it may not be functioning properly. So learn as much as you can. I highly recommend buying a used analogue oscilloscope, dual trace. These can be bought for not too much money, and you will be amazed at how much you were missing. These are very basic tools you need.
Repairing the griplets is properly done by removing the solder, adding liquid solder flux, then using fresh solder. You don't need to apply excessive solder. Also any component leads used for top to bottom connections (there are a few).
Try to approach each repair as if it is for someone you care about. You'll learn more and have something you can be proud of. Remember that just because something works, it may not be functioning properly. So learn as much as you can. I highly recommend buying a used analogue oscilloscope, dual trace. These can be bought for not too much money, and you will be amazed at how much you were missing. These are very basic tools you need.