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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: drtdiver on May 07, 2020, 10:50:54 PM
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i recently got a turbo duo with a dead cd drive. hu card games play perfect. when you press run to start a cd based game it goes busy for a few moments then says please set disk. i opened it up to check everything out and was going to do a recap but was pleasantly surprised that the board was already recapped and clean. so i started checking traces and continuity and i can't seem to find anything i did find that c164 had a missing pad and was soldered to an alternate spot on the board but seems to check out. when pressing run the laser carriage moves to the stop and sits there then the system just says please set disk. any insight on what to look for would be great. i can post pictures of the board if needed.
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Does the lens move slightly when you hit the run button? If not then this would be a more serious problem than just caps.
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yes the lens moves a little
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Okay, that's a good thing.
Without being able to see the board and the quality of the recap work done, I'd say it could be a bad lens.
However there could be bad traces for the caps. I'd test the traces for all the caps that sit below the CD drive to see if they have they are good.
Oh, and I just thought of something else. Check to see if the center spindle is the correct height. With the Black guard that sits over it, you should barely be able to see the metal portion of the circle part sticking over the top. I've seen some get pushed down to where the CD won't spin from it being stuck up against the black guard that sits under it.
CD won't spin at all if the lens won't read/is bad.
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i have tried swapping out the laser and does the same thing. I'm currently going through and making sure the traces are making contact. the spindle sits just above the black cover so it looks good no obstructions there. I'm attaching a picture of a suspect cap and trace but from what i can tell it is making good contact with what's left of the trace.
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Man, someone did a number on those cap pads.
That capacitor should be fine. Looks like it's in the correct via hole.
Does the lens bob up and down after it moves to the center of the drive when hitting run?
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Yes it bobs up and down. I’m also thinking the pots got messed with I see marker on them.
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Sounds like there was a problem to begin with. With the lens bobbing up and down this should indicate that everything with the duo is working correctly, as far as the cap change is concerned anyways. Just need to either adjust the potentiometers or replace the lens to get it working again most likely.
I would try another lens to rule that out as the problem.
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yeah I'm leaning towards adjusting the pots now. when i got this unit i picked up 2 hop m3s just incase. I've tried both of them now and still get the same thing lens bobs up and down then nothing. time to do a little research on the pots.
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After swapping out lasers and still having the same issue I started to dig into pot adjustment. Something must be wrong with the pots or in the connection between the pot and end points because I can turn vr102 and nothing happens disk never starts spinning. Same with 104
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Weird, problem could even be a faulty chip on the board.
I'd suspect one of the larger BA chips.
You should try starting up the CD drive over and over again and feel if either one of the 2 BA chips(BA6290A)start to warm up. They are supposed to get hot when the system is working correctly. If they are cool to the touch then 1 could be bad. Very rare for both to go bad.
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the chip on the bottom of the board stays cool while the chip on the top warms up.
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There is a good chance that it's bad. Only way to know is by changing it out but I would do that as a last resort. Not sure how much time you have put into messing with the lens adjustments.
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I’ve spent a bit of time trying. Can never get the disk to spin or read. Same results. I have some chips on order in the mean time I’m going to continue trying to get results before changing it.
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got the new chip installed same outcome. disk still doesn't spin.
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Then there is either a bad trace on the board somewhere or another possible chip issue. Seems weird that the lens actually bobs up and down when trying to read. Normally this does not happen when a DUO has the no disc spin up problem. Does the center of the lens show red in it when powered on? Obviously don't stare directly into it but glance at it from an angle for a quick second or even use your phone to look through to it.
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replaced the chip and now the lens will only bob up and down randomly not every time. and no red coming from the laser.
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No red from the lens usually indicates a bad lens, bad CXA1082 chip or bad traces from the CXA1082 chip to the D78C chip.
Dealing with these issues is a horrible process trying to track down the actual problem. It's taken me many tries to fix DUOs with these issues.
When it is out of my league, I send some of the chip issue systems I get to thesteve to repair because he has more experience with it than I do. Unfortunately he is super backed up with repairs right now and isn't taking on any more work.
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right on. thanks for all your help. if i ever get this thing going i will post back
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Hiii. I have the same problem, has somenone find any solution?
Regards.
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Hiii. I have the same problem, has somenone find any solution?
Regards.
Was the CD drive working prior and just recently stopped? Where is the lens positioned? If the lens is as far right as it can go, then the lens gear is stuck inside. You can poke the gear to free it up using a light to see inside and a small screw driver. Do not try to push the lens itself(Bad). Otherwise you'll have to open up the system to manually move the gear by spinning the motor with your finger if you can't see it to free it up.
If the lens isn't stuck to the far right, then I need more information from you. Does the lens move at all when you hit run on the controller? Do you get a please close lid error on the screen if the lid is open?
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I did recap time ago. It worked ok, but a day the motor didnt spin. Allways is the same: Lens Up very fast, lens down very fast, three times and stop. Sometimes I can do work if i switch the consol on and off until It begins to work again but not allways work... I think is a problem with Focus,, when I get consol works, i can play until I have to change CD. Sorry my English.
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I just prove with a new lens, and It is the same... :'(
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So it does work sometimes but not others? When it does work, can it work for a long time or does it only work for a little bit before having problems again?
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It depends of the game, for example if I can load Zaphire I can play ok but if I get to load World Heroes 2, when you select to start a game then the disc stops at a moment to start loading a second later and at this moment the problem returns and the reader stops.
Sometimes it seems to be fixed, but when I turn off the console or the reader stops for a few seconds, the problem returns.
Normaly I need about 4 or 5 attempts to charge a game
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Any advice?
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World heroes 2 always pauses during loading and then starts again on it's own. This is normal providing it doesn't stop loading and freeze altogether.
Has the DUO ever had the capacitors changed? This is a common cause for CD drive issues.
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i replaced cups one year ago, but console was working OK several months.
I dont know...