TG16 CD unit laser doesn't move SOLVED

MobiusStripTech · 05/24/2017, 09:59 PM

Like the title says, I have a tg16 CD that has a laser that isn't moving. The unit has a brand new gear, new laser, and I tried a known good motor just to be sure.

So here are things I know, the 7805 is getting 10-12v in, and 5v out. At the pins for the motor I get 7.2v on pin1 and 6.7v on pin2. At the 2.5v test pin I get 2.5v. I can apply power and ground to the motor and it will move. I can also see the motor try to move when I press play but I don't think it's getting enough juice.

Please if you have any thoughts share them. I already fixed a power issue in the dock and this is my last hurdle.

Yes I have the original power supply and it doesn't work in or out of the dock.

Solution: The BA6290A chip was faulty. Replacing it fixed the unit.

MobiusStripTech · 05/25/2017, 01:30 PM

I am wondering if the issue could be related to the BA6290A. Has anyone seen these go bad before on one of these units?

Keith Courage · 05/25/2017, 10:45 PM

Take one of the gears off and see if the lens motor spins like crazy when you hit play. Could be a dead motor.

MobiusStripTech · 05/26/2017, 12:42 AM

Even if the motor works when I supply direct voltage and ground to it?

Keith Courage · 05/26/2017, 03:29 AM

How much power are you sending the motor when you are testing it?

MobiusStripTech · 05/26/2017, 07:40 AM

It's about 10v. Which is obviously well above what it would normally get.

MobiusStripTech · 05/26/2017, 09:06 AM

I will try your suggestion though. Maybe it's working just because I supply excess voltage. Although I tried to power a different motor and it couldn't power that either.

Keith Courage · 05/26/2017, 02:35 PM

Oh, well if you already tried a 2nd motor then that most likely isn't the problem.

MobiusStripTech · 05/27/2017, 03:08 PM

So just to be safe I tried your suggestion and you were correct. The motor turns. So I guess I have to get a new motor. Does anyone know a part number for one that I can find without taking it from another tgcd?

MobiusStripTech · 05/27/2017, 03:52 PM

I found one. Actually found an old link you had in a thread Keith. Much appreciated for the assistance. Once I get the new one installed I will update as to whether that fully corrected the issue.

Keith Courage · 05/27/2017, 07:40 PM

How difficult is it to move the gears using your finger? I'm wondering if there is something binding/catching on the assembly.

MobiusStripTech · 05/27/2017, 08:44 PM

It's really easy to move. I checked the gears individually to see if there was any damage and did not find any.

MobiusStripTech · 06/05/2017, 11:56 PM

So the issue has been solved. The culprit was the BA6290A. It wasn't providing enough voltage to move the gears. I managed to find a seller with brand new units so I will be ordering a bunch. I also had a duo with the exact same issue today.

gtsamour · 06/08/2017, 02:48 PM

Has anyone else encountered a BA6290A go bad on the PCE or TG16 CD unit?

Could this be the cause if a unit that has new gear, new lens and well lubed mechanism (tamiya boron lube) sometimes spins the disc (and seems to be playing fine) and other times not?

Might be the laser (although it is new, I had replaced it myself a couple of years back) but I don't have a new one yet to try... if the new laser doesn't fix it, could it be the BA6290A?
Or is the BA6290A only responsible for moving the laser back and forth? On my system the laser moves but sometimes it doesn't spin the disc.

The 7805 isn't the cause, I replaced it with a new one.

MobiusStripTech · 06/08/2017, 11:16 PM

The turbo duo I have been repairing also had a bad BA6290A and would move the laser but not spin the disc.

gtsamour · 06/09/2017, 02:42 AM

What could cause this (the BA6290A go bad)? Is this normal ware or maybe a wrong psu connected some time before and damaged it?

Are there two BA6290A on a PCE CD? I can see two components that look like that in photos but are they both BA6290A?
If thats so.... is one for the laser movement and the other for the disc spin motor?

Quote from: MobiusStripTech on 06/08/2017, 11:16 PMThe turbo duo I have been repairing also had a bad BA6290A and would move the laser but not spin the disc.

Did the disc spin occur from time to time or never? On my unit it happens but not always... could it be the BA6290A?

MobiusStripTech · 06/09/2017, 09:18 AM

I can't say for certain what happened to the TG CD unit, but yes there are 2 of these on the unit. Only one was bad on the unit I repaired and it was the laser movement controller.

On the turbo duo, the laser would move to the inner position and that was all it would do. The disc would never spin. That one, someone had messed with the chip before and moved it to the bottom of the board as well as broke off one of the resistors on the board. So it was a bit more obvious.

gtsamour · 06/09/2017, 11:36 AM

Quote from: MobiusStripTech on 06/08/2017, 11:16 PMThe turbo duo I have been repairing also had a bad BA6290A and would move the laser but not spin the disc.

Thank you for the info

My PCE cd unit was working fine (new caps, gear and lens installed by me, pots adjusted too) until I disassembled the unit to whiten it with retrobright.
When I put it back together carefully, the unit worked but started to behave strangely, some times it booted and loaded fine. Other times it seemed struggling to boot and the laser seemed to go back and forth with the disc spinning but failing to load. Other times the disk didn't spin.

Opened it up more than once but couldn't see anything wrong with it (ribbons half way in, clogged gears etc). While trying to find out what was wrong I ripped the wide ribbon right through, so now I'm waiting for the new one.

So I still don't know what was wrong in the first place. I'm thinking I might have damaged the ribbon without noticing while I was putting the unit back after the bleaching, or the laser started to die although it was new or the BA6290A started acting up. I ordered two from ebay just in case.. Easy to find and thankfully cheap.

Fingers crossed, I hope replacing the laser will be all that's needed.

gtsamour · 06/09/2017, 05:50 PM

Thank God it was the laser. Seems to be working OK now, cd spins every time. Every now and then it may take longer to load Dracula X but I guess that has to do with the disc being a CDR, all my pce cd systems do that sometimes.

It seems I damaged the ribbon without noticing when I took it apart to retrobright it.

Do the pots need re adjusting every time the laser is changed?

MobiusStripTech · 06/09/2017, 10:48 PM

Possibly. It's a different laser so the pots may need to be compensated in return.

gtsamour · 06/10/2017, 04:02 AM

It was a pain finding a new KSS-220A and it cost me 50 euros postage included... but what can you do... there is an Austrian guy on ebay selling new Denon KSS-220A and still has 6 of them for sale if someone is interested.
If someone knows of a different source for new ones it would be great to let us know.

gtsamour · 06/10/2017, 05:22 PM

I managed to adjust the pots with the new laser installment, frankly there was no change compared to the previous settings....

one thing is strange though and I would like your insight....

all cd-r games I tried (Taiyo Huden), load fast and play fine (data loading ok and all audio tracks play crystal clear).
But two genuine pressed audio cds out of a total of 11 I tried, will not play OK (skipping after a later track on one and bad audio on the other, with very faint static like distortions but clearly audible).
The other 9 audio cds play absolutely fine, all tracks.

How can this be explained? The 2 problematic audio cds don't have any scratches or dirt on them.

The weird thing is that I tried to adjust the pots using one of the "bad" audio cds and it was impossible, it wouldn't play OK no matter what.

And finally, this "bad" cd was playing fine with my previous laser (before I replaced it)....
The previous KSS-220A was Sony and the new one is Denon.... could that make a difference? (maybe the laser power setting is lower on the Denon)

MobiusStripTech · 06/12/2017, 09:59 PM

It's hard to say. From my experience these lasers can be very picky. They all seem to find something they don't like. Your best bet might be to have someone with a scope try adjusting it for you.

gtsamour · 06/13/2017, 12:40 AM

But isn't that weird, that it would play all CD-Rs OK, it will play silver pressed audio cds OK and just two out of 11 of them have problems?

I thought that all silver pressed cds have the same reflectivity (and better than any CDr's) and thus, I would expect either all of them to be playing OK or none of them... isn't that so?

Also I would expect the silver pressed audio cds to be playing OK first and then any CD-R due to better reflectivity. In my case all CDRs i made play absolutely fine with excellent loading times, every time.

As for an Oscilloscope... would these cheapos that go around ebay suffice? http://www.ebay.co.uk/itm/2-4-TFT-Digital-Oscilloscope-Kit-DIY-Parts-Acrylic-Case-Cover-1M-HOLD-Function/282518516105?_trksid=p2045573.c100505.m3226&_trkparms=aid%3D555014%26algo%3DPL.DEFAULT%26ao%3D1%26asc%3D43781%26meid%3Deaa4abd3c8bb4e77874980abb0eedcc7%26pid%3D100505%26rk%3D1%26rkt%3D1%26

MobiusStripTech · 06/13/2017, 05:13 PM

I can't say for certain why 2 of your CDs won't play, I am really just speculating. For the scope you would not want to use one of those. The cheap scopes don't support high enough frequency and generally the sample rate is too long.

gtsamour · 06/14/2017, 01:34 AM

Steve said it might be due to more thickness on these two.
I'm suspecting that my issue is laser power related..... I was unable to make two audio cds play by adjusting the pots but 9 others play OK, so it has to be laser power related, maybe it needs to be a tiny amount higher.

I may try to increase the power just a little bit and see what it does.

mario_pic · 06/22/2017, 12:04 AM

iv seen a short caused by not useing the silver insolator thats under the top cover cause drive to short chould be that