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“Junk” PC Engine CD-ROM^2

Started by CZroe, 12/31/2017, 12:51 PM

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CZroe

Just received and tested with an audio disc before work. The laser bobs when I trip the lid sensor but the disc does not spin. I didn't want to force the carriage back without checking out the gear first so I don't know yet if it returns to the center (ran out of time before work).

Three silver screws and one brass-colored screw on the outside. PCB screw is silver colored. Did someone mix this up or it one of the external screws supposed to be different?

Other than a loose dust ball it was pretty clean inside. It looks like the gear has already been replaced and all three spin easily with no skipping. The rails and corkscrew gears seem to have fresh grease (nothing dried or caked). The replacement middle/center gear is clear, unlike the ones I see from Console5 or eBay.

Despite the clean internals, the bottom side of the lid has a layer of dust on it, so perhaps it's just a dirty laser? If a laser were so dirty that it couldn't see the disc, would the disc still spin?

A sticker on the laser assembly says "KSS-220A." Isn't that the compatible replacement and not the original? Perhaps it just needs to be tweaked.

I haven't dug all the way in to check out the rest of the Mylar flexible flat cables but they are intact everywhere I can see. The adhesive piece holding one of them to the laser motor seems to have slipped a bit over the years but that doesn't seem to be a problem.

I'll see if the laser homes when I get back, but what would you check next? Thanks!

Keith Courage

some of these drives came with a KSS 220 and others came with a KSS 162. It's completely normal to see a KSS 220 in there.

can you tell if any of the capacitors have been replaced?

CZroe

#2
Oops. Looks like I forgot to post a link to the pics:

https://imgur.com/a/SJNes

Quote from: Keith Courage on 12/31/2017, 03:08 PMsome of these drives came with a KSS 220 and others came with a KSS 162. It's completely normal to see a KSS 220 in there.

can you tell if any of the capacitors have been replaced?
Ah. So it could be a late production then. Could that also explain the clear gear? Perhaps NEC knew it was becoming a problem by that time and revised it.

I didn't get to inspect the caps super closely yet but they all looked good to me earlier (not that they wouldn't test bad anyway). The PCB looked untouched and if the clear gear is sometimes stock/factory and the screw colors are normal then I might assume so. The KSS-220 is anecdotally more failure-prone and with all the strange dust on the inside of the lid I still wonder if it's just a dead laser.

wolfman

Quote from: CZroe on 12/31/2017, 12:51 PMJust received and tested with an audio disc before work. The laser bobs when I trip the lid sensor but the disc does not spin. I didn't want to force the carriage back without checking out the gear first so I don't know yet if it returns to the center (ran out of time before work).
Sounds like misadjustment of the laser, that´s why it´s bobbing up/down - it looks for CD but cant find it. Try the pots on side for adjustment. If you get it to spin up the CD you are in the right direction.
recent addition: Japanese Language Skills, A1 proficiency level
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CryptoCoin Warrior
My Setup: PC Engine LT, CD-ROM², IFU-30
AKA woolfman on AtariAge, PlanetVB, Circuit-Board.
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CZroe

Capacitors are original (most stamped on top with an "88" date code). No sign of attempted replacement. Even in close inspection they look like they are in great shape. Looks can be deceiving, but since it powers up and the cap kit is backordered from Console5, I figure I'll keep troubleshooting for now.

The lens does return when powered up.

The laser center/home position limit switch does work.

Haven't removed the laser mechanism itself to look for cable cracks but everything I have seen looks intact.

Quote from: wolfman on 12/31/2017, 09:05 PM
Quote from: CZroe on 12/31/2017, 12:51 PMJust received and tested with an audio disc before work. The laser bobs when I trip the lid sensor but the disc does not spin. I didn't want to force the carriage back without checking out the gear first so I don't know yet if it returns to the center (ran out of time before work).
Sounds like misadjustment of the laser, that´s why it´s bobbing up/down - it looks for CD but cant find it. Try the pots on side for adjustment. If you get it to spin up the cd you are in the right direction.
I don't have a game CD to test. I assume I should adjust with a pressed disc, so is there an adjustment guide that incorporates an audio CD?

Keith Courage

#5
if this is one of the CD drives with the clear looking gear inside of it then I would not worry about the capacitors. Not saying they couldn't be a problem at some point, but I've never come across one of these CD drives that has the clear stock gear where the capacitors have been a problem.

I would also recommend trying to make some small potentiometer adjustments on the side of the motherboard. If this does not get things going again then this drive might need a replacement lens.

you could probably do this using a regular audio CD as long as you have one with a lot of songs on it. The trick is to get things reading well with songs within the first 1-3 tracks and then songs near the outer edge of the disk which would be around maybe track 18 through 22. obviously depends on the length of each song as to how high of a track number you would need to move up to.

CZroe

Quote from: Keith Courage on 01/02/2018, 03:40 PMif this is one of the CD drives with the clear looking gear inside of it then I would not worry about the capacitors. Not saying they couldn't be a problem at some point, but I've never come across one of these CD drives that has the clear stock gear where the capacitors have been a problem.

I would also recommend trying to make some small potentiometer adjustments on the side of the motherboard. If this does not get things going again then this drive might need a replacement lens.

you could probably do this using a regular audio CD as long as you have one with a lot of songs on it. The trick is to get things reading well with songs within the first 1-3 tracks and then songs near the outer edge of the disk which would be around maybe track 18 through 22. obviously depends on the length of each song as to how high of a track number you would need to move up to.
Thanks for your help! I spent a few hours checking inside more thoroughly. I checked the ribbons and lubricated but now the laser doesn't move properly. :( I vaguely recall seeing something about this in the laser replacement guides so I'll look there next.

I know it's not from the three gears because the laser assembly slips when I turn the worm gear directly even with the motor completely removed. The laser assembly seems to be catching on the smooth rod even though it moves freely when I remove it with the whole lens assembly. The teeth that engage with the worm gear under tension looked fine just before this started.

I used the "3 in 1" oil that many refer to as "sewing machine oil." It's very light so I apply it sparingly with a small paintbrush.

FFC Mylar ribbons are fine but all the pots on the main PCB seem to have small cracks on the top of their plastic shroud. Doesn't look like it would cause an issue but I'd love to know the typical measurements so I can tell if someone went nuts on them.

I can barely tell that the laser is lighting up though. How bright should it be? I'm already on the lookout for a replacement.

I've been digging and digging for a non-Duo, non-Super adjustment guide for the CD-ROM^2 and I'm just not finding one. Even threads where the OP clarified repeatedly end with someone posting another Duo guide or something. Do the same component names on a Duo correspond to a PCE CD-ROM^2? In other words, is VR1 on a Duo the same as VR1 on a PCE CD-ROM^2 so I can follow the Duo guide on a non-Duo CD-ROM^2? If so, none of the Duo guides I see make that clear. If not, what pots correspond to the ones in the guides?

Keith Courage

I do all my lens adjustment by ear. I've done it so much that I can tell by sound which needs to be adjusted. I can't really make a guide for that.

You are going to have to do this by process of elimination. Just start by turning one of the pots any given  direction and then test the CD drive. If it makes no difference then try turning it the opposite way. If that doesn't do anything then put it back to it's original position and move onto another potentiometer and do the same.

CZroe

Console5's lubrication guide said not to use the light 3-in-1 oil I used and also said not to lubricate the end caps on the worm gear. I did both, which probably explains why my laser mechanism is no longer moving properly. They describe that the worm gear can't shift like it was designed to do due to suction/vacuum at the lubricated end cap. I guess I'll have to bathe these parts in isopropyl alcohol and regrease with white lithium or something while avoiding lubrication in the endcap. Hopefully that'll get my laser moving properly again!

I really don't think that the laser is supposed to be this dim and I've never heard of a pot adjustment that brightens it so I think I'll replace the laser before I fiddle with the pots... or at least see if a working Discman with a compatible laser looks brighter first. I went ahead and ordered a $21.xx Discman. If it looks the same (dim/almost impossible to see) then I'll fiddle with the pots before I swap. Worst case: Having a spare can't hurt. :)

Keith Courage

Yeah the red light shouldn't be very dim. In fact, it's supposed to hurt your eyes if you look at it. lol

D-2
D-4
D-11
D-12
D-33
D-34

Discman models that have compatible lenses.

CZroe

Quote from: Keith Courage on 01/05/2018, 02:51 AMYeah the red light shouldn't be very dim. In fact, it's supposed to hurt your eyes if you look at it. lol

D-2
D-4
D-11
D-12
D-33
D-34

Discman models that have compatible lenses.
Thanks. I ordered the Sony Discman D-180K from a list deeper in the "Laundry List" thread. ;)

Others I gathered from the thread:
Radio Shack Realistic CD-3200
Sony Discman D-3, D-9, D-10, D-15, D-20, D-T20, D-22, D-20, D-40, D-55T, D-90, D-99, D-100, D-802K.

I'll know right away if the laser brightness is way off. Thanks.

CZroe

#11
Yesterday I received the Sony Car Discman D-180K and confirmed that it reads CDs just fine. I also took apart the CD-ROM^2 to clean out the 3-in-1 oil and reassembled to confirm that the laser will home. It does.

Today I disassembled the D-180K and confirmed that it has a KSS-220A. The laser swap went off without a hitch. The drive has the same behavior: laser homes, attempts to focus several times, then powers off with no disc spin.

I moved on to tweaking the pots. I started with VR104 and got disc spin when I went counter-clockwise nearly the full range. I tried playing back an audio CD but it was very skippy. I got no improvement by adjusting VR103. Turning VR105 counter-clockwise definitely improved the audio playback so I found a spot where it sounded best and cycled power. I could no longer get disc spin.

I tweaked back and forth and returned VR105 to the original position but I still could not get disc spin. I set everything back to the original positions and tried VR104 again but I still can't get anything. I continued to play around with those three pots and even tossed VR102 in the mix but after hours of messing with it I still haven't gotten a CD to play.

I'm at a loss. I was so close! Does this mean I burned the laser out or something? I don't understand why I can't get back where I was even after returning the settings.

Edit: I began tweaking VR101 counter-clockwise and got disc spin but no audio playback. I kept tweaking that direction and the disc would spin then reverse and start spinning BACKWARDS. After tweaking VR104 and going back to the beginning of where it would just spin on VR101, I got choppy audio playback again. I adjusted VR105 until it was clear and then tapped the side. The track would always resume from the beginning. I skipped to the last track on the disc and tapped the side and playback skipped back to the middle of the previous track (even the number counted down). Tapping again would skip back again. I could go all the way back to the beginning that way. I power-cycled and now I'm back to square one (can't get disc spin). I've tweaked a million different ways and I just can't get a consistent and repeatable result that persists through a power cycle.

Edit 2: If Console5's tech wiki is accurate, the functions of each pot do correspond to the same pots a Duo (VR101 on a CD-ROM^2 is the same adjustment and VR101 on a Duo, VR102 is the same as VR102 on a Duo, etc). I assume that this means I can follow a Duo's adjustment guide, which I haven't seen explicitly stated anywhere despite looking for that specific info. I set everything back to their original positions and followed BlueBMW's guide where he advises to start with VR102. Tweaking VR102 restored disc spin and skippy music playback. I already knew that VR103 doesn't help and my results were already as good as or better than the guide suggests after VR103, so I skipped VR103 and moved on. Again, VR105 clears up the skips so I set that to the middle of the range where the skips go away. It now spins up and starts audio playback reliably, but the recovery when I induce a skip still confuses me. It can resume/recover when I induce a skip but it doesn't recover at the right place. It usually goes to the previous track. The track number on the display counts down and everything, so the player is aware that it has changed tracks. Is this intended behavior?

PapaSmurf

Quote from: CZroe on 01/10/2018, 12:05 AMIt now spins up and starts audio playback reliably, but the recovery when I induce a skip still confuses me. It can resume/recover when I induce a skip but it doesn't recover at the right place. It usually goes to the previous track. The track number on the display counts down and everything, so the player is aware that it has changed tracks. Is this intended behavior?
AFAIK, there's no position recovery on these old CD-ROM drives.  When I was refurbishing my Duo, and was having some problems, I induced skips noticed that it doesn't seek back.  I'm playing with a CD-ROM2 now and when I tap on it to induce a skip, it does not recover its old position either.  I'm going replace that middle gear even if it's working right now, because I know it's only a matter of time before it breaks.

I also noticed that it's absolutely essential that the laser assembly glide smoothly and freely.  Dirt, hair, or minute obstructions can cause playback problems.  If the laser cannot home completely, the CD won't spin.  And if the CD system detects an obstruction when seeking, it won't work at all until you power cycle it.

CZroe

#13
Quote from: PapaSmurf on 01/11/2018, 10:15 AM
Quote from: CZroe on 01/10/2018, 12:05 AMIt now spins up and starts audio playback reliably, but the recovery when I induce a skip still confuses me. It can resume/recover when I induce a skip but it doesn't recover at the right place. It usually goes to the previous track. The track number on the display counts down and everything, so the player is aware that it has changed tracks. Is this intended behavior?
AFAIK, there's no position recovery on these old CD-ROM drives.  When I was refurbishing my Duo, and was having some problems, I induced skips noticed that it doesn't seek back.  I'm playing with a CD-ROM2 now and when I tap on it to induce a skip, it does not recover its old position either.  I'm going replace that middle gear even if it's working right now, because I know it's only a matter of time before it breaks.

I also noticed that it's absolutely essential that the laser assembly glide smoothly and freely.  Dirt, hair, or minute obstructions can cause playback problems.  If the laser cannot home completely, the CD won't spin.  And if the CD system detects an obstruction when seeking, it won't work at all until you power cycle it.
Thanks! Comforting to know. The adjustment guides for the other platforms say to induce a skip at an early track then a later track and ensure it can recover from both, but they must mean "recover" as in "audio resumes" even though it did not recover the old position.

Though I still don't have my Turbo ED or a System Card, I moved on to testing audio CD playback on the dock last night. My Atari 5200 plug was *almost* perfect (fits, ~11v, ~1.5A) but it's the wrong polarity and I'm not about to splice it up for a TurboGrafx-CD dock PSU. Instead, I went to a thrift store and found a 12v 3A "Hyundai" brand switching PSU that fits (5.5x2.5mm). I reversed the polarity and brought the voltage down with some diodes. It works perfectly! Now I just need some discs and a SysCard of some kind.

I actually ordered a couple PCE CDs last night and the replacement Turbo ED shipped from the Ukraine 18 days ago (can be made to work as a System Card). It took 20 days to arrive after my first Turbo ED shipped but that one arrived Christmas Eve and wasn't delayed by Christmas/New Years like this one. The PCE discs will very likely be here first (they were already in the country). Very close to finishing this. Thanks again, guys!

My advice to anyone else who finds themselves attempting to adjust this:
start with VR102, just like BlueBMW's advice for a Duo... or just order the $89 drive from gamedoctorhk.com, since it comes with an adapter and works without a $20 gear or laser. I ended up spending about the same but with a lot more headaches. I'm going to reassemble the Discman D-180K with the old PCE CD-ROM^2 laser to see if it works there. Because I removed it without adjusting, there's a good chance that I have a working spare out of all this, at least.

IMG

CZroe

SUCCESS!
I finally got my replacement TurboED to use as a System Card. Noticed that the patched BIOS you use affects a bit more than the Backup RAM manager and load screen though. :)

Next up: Test CD-Rs and tweak if necessary. Gotta order Verbatim AZO or Taiyo Yuden discs first. I know counterfeit discs are so prolific that it can be hard to ensure you're getting real ones. Wish me luck!