Turbo CD plays music CDs stand-alone, but nothing else.

[cr4zymanz0r]

Ok, I got a Turbo CD in today and at first it wouldn't spin up anything when hooked to the system or trying to use it as a stand alone CD player.

I opened it up and the laser sled as at the very end of the track, so I turned the gears to move it back forward and re-greased the sled trail (whatever it's called. The part that looks like a giant long screw).

After that, I put it back together and now it plays music CDs fine as a stand-alone player (detached from the system base). It played every track of a pretty long music cd and I heard no issues while it did so. However, when I hooked it back up to the system it won't load games or music cd's (does it support playing music cd's from the bios?). When i press run the "PC" LED display lights up, the disc starts spinning, and i hear it seek some, but it continues to just sit at "Just A Moment...".

Two more details: I've tried with 2 separate TG16 systems with the same result (if that even matters). The other detail is I do not own a real system card. Now I am using a Turbo Everdrive to load the System Card 2.0 US bios. Now from what I understand, the extra RAM is built into the CD unit (or maybe it's the CD base, whichever). So, if the 2.0 card does not have any extra RAM in it then it should work from the Everdrive and I believe I've seen people say they use it for that. I tried a non-Super CD game (Last Alert). (I'm aware this same method would not work with for the System card 3.0 since it contains additional RAM onboard).

I don't think the Everdrive portion is the issue, but if you've done testing yourself to the contrary then please let me know. Otherwise, anybody have any idea what the issue is?

[Keith Courage]

From what I have read the everdrive can't emulate a cd system card. that is most likely your problem.

[cr4zymanz0r]

Now the CD-ROM is magically back to not spinning discs even when used as a stand alone CD player.
EDIT: .....Now it's back to playing music CD's stand alone.

[cr4zymanz0r]

Ok, did more testing. Anytime I leave the CD-ROM unit unplugged for an hour and a half (maybe even less), it goes back to never even spinning up a disk. If i try to use it as a stand-alone CD player then when I hit play it just shows a solid 0 for the track listing on the LED display and never spins the disc.

Now if I leave it plugged in for 15min or so it will go back to spinning up discs and working as a standalone CD player. However, then when it shows something on the LED display (such as "PC" when trying to boot a game, or the track listing number of a music cd) it is flickery. The closest thing I can describe is it's somewhat like the effect you see when you record what's being displayed on a CRT screen.

This sounds like capacitors to me, but I didn't think the regular Turbo CD was known for bad caps. None of them appear to be leaking or puffy either.

[Keith Courage]

Sounds to me like the CD lens gear is getting stuck again. This happens when the gears get old. The inner hole swells making it harder to turn. I bet it you start it by hand it will work just fine again. If this is the case you will need to either change the gearing or drill out the center hole slightly on the middle gear to keep it from sticking.


Also, some capacitors can still go bad in these things without signs of where. However, I've never seen the PC led flicker in the way you describe from bad caps. The usual bad caps are in the center of the board. Try changing the 1UF, 4.7UF, 22UF, and 100UF caps. They are all in a row.

Also, after changing the caps if nothing changes I'd try adjusting some of the potentiometers.

[cr4zymanz0r]

Ok, lots more troubleshooting has been done but to little affect.

1.) I replaced every single capacitor in the CD-ROM portion and absolutely nothing changed at all. It still plays audio CD's as a stand-alone CD player, but won't load game discs or music discs from the bios/system card. It also still had to "warm up" for about 15min being plugged in before plugged in, but if I opened it up and turned the gears myself it seemed work immediately after that.

2.) I took out the middle gear and gently drilled the hole a little by hand to make the hole slightly bigger. After that the tension between the gears was lessened and it was easier to turn by hand to. So far after this it hasn't needed a "warm up" period to start playing a music cd, but otherwise nothing else changed.

3.) I got a legit 2.0 System Card and it has the same results as loading the bios from the Turbo Everdrive. Any game disc or music disc just says "Just a moment..." on the screen and shows "PC" on the CD-ROM display. I even left it running for 20 or 30min and the disc was still spinning but made no progress. If i open the disc door it recognizes that, so it's not locking up.

4.) I tinkered with adjusting the potentiometers, but I couldn't find a good guide for which ones do what and what they need to be adjusted to. All I accomplished was making music CDs misbehave, then changing things back so they worked correctly again.

Any ideas?

[Keith Courage]

Just for the sake or trying it you should clean the rear I/O port on the cd drive using rubbing alcohol and a tooth brush. I've come accross a few drives with the symtoms you describe due to dirty connections. One drive I actually had to change out the whole port.

Otherwise if it still won't read any discs then there is either a bad trace or chip somewhere on the motherboard. Maybe Thesteve can chime in as to where the problem area might be?

[cr4zymanz0r]

Well, more troubleshooting and more confusion.

1.) The contacts on the connectors looked fine and shiny, but I decided to clean them anyway for good measure. However, before cleaning them there was a whole 2 or 3 times that I was able to get it to load to the CD player with a music CD on the System Card. However, there was no rhyme or reason to it. If it loaded up one time, without adjusting how far the connector was or anything I could turn the system off, back on, and it wouldn't make it back to the System Card CD player again. Also, the few times it did make it, it would recognize the amount of tracks on the CD, but could not play any of them (all while the stand-alone CD player functionality continued to be fine).

2.) After cleaning the connectors, nothing changed.

Now, I got a good deal on yet another untested but "worked last time it was used years ago" Turbografx CD and base so now I have 2 CD-ROMS and 2 bases. When I unpacked it today the first thing I did was test it as a stand-alone CD player. It played a music with no issues at all. I didn't have to tinker with it at all.

So next, I hooked it all up and......same exact issue. "PC" display shows up on the CD-ROM and all i get is "just a moment...". So i have two TG16s, two Turbo CD-ROMs, and two bases. I've tried various combinations of them together and the results are the same. At this point I'm extremely baffled.

===================================

One thing to note (and I don't believe it should even matter unless there's something about the Turbo CD I don't understand) is I'm not using the original AC adapter since I don't have that. I'm using a 9V 3A adapter. Now before anyone automatically deems this the culprit, I'll give some background info. Most of these retro consoles use a 7805 voltage regulator inside of them that brings the incoming AC adapter voltage down to 5V to supply to the system. The minimum voltage the 7805 can accept is 7.2V from what I've looked up. Now I've seen consoles where the AC adapters were 9V, 10V, 10.5V, and maybe other values. These also had 7805 regulators inside, so running them on the off a 9V adapter with the proper or higher amperage has never been an issue.

I opened up one of the Turbo CD base units and sure enough it also has a 7805 regulator in it, so it appears it should work fine with a 9V AC adapter as long as the amperage is high enough. Right next to the 7805 are two "C2275" components that are apparently power transistors (

), but I don't know much about that them so I don't know if that would affect the situation. I'd be interested to hear from anyone who's an expert on the TGCD's power set up and people who have successfully used non-official AC adapters.

[turbokon]

That is mostly likely the cause.  There are likely circuits in the unit that draws voltage from the unregulated side. 

[turbokon]

Also the tg dock is rated at 11v.  9v power supply is to low.

[cr4zymanz0r]

DOH!

Well, this is the first time I've ever encountered a retro system (the CD base in this case) with a 7805 regulator that can't take 9V (or maybe even lower) and work properly.

I just did a quick and dirty test. I supplied 12V to the dock (measured at 11.92v) from a PC power supply.....booted right away. Currently running Ys Book I & II with no issues.

I'll need to test both of them now thoroughly and find a proper AC adapter replacement. I'll report my findings later after testing. Let me know if anybody knows of a good priced proper AC adapter replacement.

Thanks for the help and suggestions though. I feel a little dumb now, but I'm happy that things look very promising now 

EDIT: Both setups are working fine so far. I also confirmed that a Turbo Everdrive can load the System Card 2.0 bios and games work fine.

[Keith Courage]

Wow, all that work to find out it was the power supply? What a bummer. Well at least it works now.

[turbokon]

Cool, good to hear.  I get all my turbo & pce power supply from retrogamecave.com.