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Adventures of buying a Broken PCEngine and Briefcase from ebay

Started by pceslayer, 03/08/2009, 01:08 PM

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pceslayer

I was browsing ebay and found a listing for a defective PCE interface unit with the CDROM and a Core Grafx for $48 plus shipping. I thought to myself what the hell I'll give it a try.

Well it finally arrived yesterday afternoon and I began to troubleshoot the unit. Seperated the CDROM and PCE and powered them on individually.

First I test the CDROM unit. Ok it spins up, makes some nasty noises and stops spinning... So its a Laser issue maybe?

Now I attempt to power on the Core unit and get absolutly nothing, not even a flicker on the screen.

So I dissassemble the unit and this is what I find...

IMG
IMG
A nasty crack in the mainboard thats about 2" long and severs traces along the bottom and top of the board.(*note* Pictures are taken after I scraped the board to expose the traces)

So with some patience I follow the traces and attempt a repair.

IMG
**placeholder for top pic**
ok soldering done(green circles indicated areas where traces were severed)

IMG
now some hot glue to hold the wires in place

IMG
reassembled

IMG
testing... YAY!


So next i'm going to dissassemble the interface unit and CDROM to see whats going on.


Also, does anybody know where I can purchase a region mod preassembled PCB on the cheap?

ooPo

That's a nice quality picture for a projector on a classic system. Which model is it?

pceslayer

Quote from: ooPo on 03/08/2009, 03:35 PMThat's a nice quality picture for a projector on a classic system. Which model is it?
Its a Sharp XG-C60X... a little old, but it handles 480i pretty well.


Ok now... I attempted a laser swap with a working Sony Discman D-33, but it is acting the same as before.

It spins the disc up and sounds like its reading, but after a few seconds stops and powers off.

So upon closer inspection I found this...

IMG
a broken cog :(

It seems to still spin pretty decently and I'm not really sure what effect this has on the lense sled. So... What to do now...


So does anybody know where I can get this tiny gear or another solution?

Also what should the POT on the laser be reading for the PCE/TG CD unit?

chop5

excellent job on restoring that pcengine  =D>

those cogs are a real quest as you can see in other threads. so far no ones found a replacement
AKA jetblue
Gentlemen behold...The chopsado!
IMG
tg-16 region converter or some weird bow tie

pceslayer

Quote from: chop5 on 03/08/2009, 07:24 PMexcellent job on restoring that pcengine  =D>

those cogs are a real quest as you can see in other threads. so far no ones found a replacement
Thanks man, but... awww thats not what I wanted to hear :(


Question to anyone who would know....

Are the PCECD and TGCD interchangable?

Zeon

Quote from: pceslayer on 03/08/2009, 07:28 PMAre the PCECD and TGCD interchangable?
Yep parts wise they are nearly identical and as a result a tg-cd can be used on a pce system and vice versa. Yes those cogs are evil, Nec cheaped out on that one cog for whatever reason, and as a result they get very brittle and break from age. Numerous tg-cd's and pce-cds have this issue and it's highly frustrating. Good luck finding a compatible gear, likely someone will have to get a custom one made and it's not going to be cheap. To date I have not heard of a reliable existing source of these gears. Good luck man.

papa_november

     I have a dead TG-16 drive that you might be able to salvage an intact gear from. Failing that, you could always try tracking down a CDR-35D, as the whole CD mechanism in that drive is directly exchangeable with the TG-CD's mechanism.

pceslayer

Quote from: papa_november on 03/08/2009, 08:38 PMI have a dead TG-16 drive that you might be able to salvage an intact gear from. Failing that, you could always try tracking down a CDR-35D, as the whole CD mechanism in that drive is directly exchangeable with the TG-CD's mechanism.
I PM'd you about the TGCD drive...

I was really trying to keep this project as cheap as possible...

The wife gives me the evil eye everytime I buy old broken stuff lol

NecroPhile

Nice job of saving a PCE from the scrap heap and good luck on resurrecting the CD.  Now you need to change your name to something more fitting - pcesavior, perhaps?
Ultimate Forum Bully/Thief/Saboteur/Clone Warrior! BURN IN HELL NECROPHUCK!!!

PCEngineSales

Is it just the plastic that needs restoring or what?

If it is just the plastic there is no reason why these cannot be easily molded and a replacement made out of epoxy glue.

How the hell does the board in original units get cracked in this way? I have two like this and it's unfathomable. I did not attempt a repair on either because so many traces are cut it's not worth the time taken. It's a better idea time-wise to use units like this (cracked right across the PCB, unlike yours) for parts for other less time consuming repairs. I already took the HuCARD port out of one and used it to fix a white engine with a port so corroded I couldn't get it to conduct after thorough cleaning. My other reason for not wanting to fix the heavily cracked boards is I sell my consoles and somebody might buy one, take it apart and whine about it. And I wouldn't want to sell it for less than the value of a non restored unit, after all that work done on it!

One's cracked right across the lower part of the board, nowhere near the EXT port or power in so how it's happened without the PCB being out of the machine and somebody stepping on it at some point, I've no idea.

I've fixed plenty of consoles cracked round the joypad in port though. You need now to fill that console with steel strength epoxy to stop the crack growing on the board.
https://retro-access.com/ - Modded consoles and SCART cables for retro consoles and computers. We ship worldwide.

pceslayer

@Necromancer
thanks man.. I <3's me some PCEngine

But, ive had my pceslayer tag for like 11 years now... I'd be hard pressed to change it  [-( lol.

@pcenginesales

Its just worn/broken teeth on the gear... and I have no real Idea of where to start for molding the gear, I guess I can google a molding kit.

Also I don't plan on ever removing the Core from the briefcase once all my stuff is up and running, but I think I will epoxy the shit out of that side of the board when I open it up again for my region mod.




Answering my original question about finding a regionmod... never mind, I found the IC's online and ordered a few.

Shawnathan

I need to get me a gun to do repairs like such. you guys are some serious badasses when it comes to repairing these systems!
Came to chew bubble gum and kick ass, but I don't know how to chew

pceslayer

Ok so ive given up on searching online for this compound gear.  :cry:

And it is far too expesive to have it remolded...(That is unless we all chip in to get a few hundred made and offer them up for sale on ebay or something. )

I guess in the next few weeks i'm just going to order a CDR-35D and pull out the laser assembly. I found a place that sells them for $45 with $10 shipping.

In the meantime, if anybody has a dead drive and doesn't mind giving it up for cheap, I'll take it off your hands!

TheMilford

Quote from: pceslayer on 03/17/2009, 11:10 AMI guess in the next few weeks i'm just going to order a CDR-35D and pull out the laser assembly. I found a place that sells them for $45 with $10 shipping.
can you share where you these drives can be found? ;)

Also, couldn't you just steal this gear from another cd transport? just figure out what make the transport was and figure out what models used it. I bet you can find cheaper drives that use that same gear.

Duo_R

that is the magic solution that many a people consider to be the Holy Grail of TG-CD repairs.....

Quote from: TheMilford on 03/17/2009, 08:57 PMAlso, couldn't you just steal this gear from another cd transport? just figure out what make the transport was and figure out what models used it. I bet you can find cheaper drives that use that same gear.
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pceslayer

Quote from: TheMilford on 03/17/2009, 08:57 PMcan you share where you these drives can be found? ;)

Also, couldn't you just steal this gear from another cd transport? just figure out what make the transport was and figure out what models used it. I bet you can find cheaper drives that use that same gear.
wtf... why didnt I think of that?

Its a pretty standard design Sony used back in those days... hmmmm where to start...

TheMilford

First off... what is the model on the CDR-30(A) transport? Did NEC make their own transports or did they use Sony or Phillips like everybody else?

pceslayer

I believe they used a Sony.

I'll take apart my CD unit later today and see if the transport has a stamp anywhere on it.

A side note... after a quick search I found a few old Sony pickups that use a very familiar looking compound gear in the same spot, but obviously I can't compare them accurately from a pic alone.

I found a gear in a old laptop cdrom unit thats the right size, but has 2 less teeth in the larger gear and 1 less tooth in the smaller pinion. I'm going to try it out anyway damn it!

pceslayer

Ok so I dissassembled the unit and found no markings on the assembly. The only markings are on the Laser and on the 2 motors.

Also the gear fit perfectly, but it didn't spin quite right... :(

TheMilford

Quote from: pceslayer on 03/19/2009, 02:36 PMOk so I dissassembled the unit and found no markings on the assembly. The only markings are on the Laser and on the 2 motors.

Also the gear fit perfectly, but it didn't spin quite right... :(
count the teeth.

pceslayer

The original gear has 23 teeth on the larger cog and 15 teeth on the smaller cog.

the one I found has 21 teeth on the larger cog and 14 teeth on the smaller cog.


But i don't think the tooth count is the reason for it not spinning... I have a theory

pceslayer

Well after attempting a region mod on my Core for the 15th time, something horrible happened... :cry:

One of the big 21 pin gray ribbon cables had snapped almost completely off the mainboard.  :oops:

After looking at it for a minute or two I couldn't think of any way to properly reattach the cable.

So I decided to rewire both of them... 2hrs later this is my result.

IMG
yummy wires
IMG
Bottom of HU Slot PCB
IMG
Top of HU Slot PCB (Yellow wires are from my failed mod attempts)
IMG
love this game!


and well it works as normal now... Yay?

I'm not sure I want to attempt the region mod again   :|

Duo_R

if everything is working throw down some hot glue at the base of the wires for strength.
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pceslayer

Well crap... I thought I was having a good week, but noooo!

My Core locks up at random intervals with a nasty screen glitch now... and here I thought I was done messing with it.

I'll attempt to resolder the connections to the HU PCB. When all closed up, it seems to be a under bit of pressure where it makes contact with the expansion port.


But I got my CDROM to read a music CD! It clicks around alot and the audio sounds like scratchy garbled crap, but it reads!

papa_november

Why didn't you just cut up an IDE cable and use that to wire up the slot?  A zillion Ethernet cable wires can't possibly be good for keeping the noise down.

PCEngineSales

I had that issue with the cable snapping off the board before, it's a pretty simple fix, you use a solder sucker to suck out all of the solder from the holes and then you take the ribbon cable still attached to the HUcard port part, you cut off the broken bit to produce a neater cut, then you take a stanley knife, score each side and pull off the plastic from each wire with some pliers. Then you tin each wire (it will melt the plastic a bit in places but this doesn't matter) feed the cable back into the holes and solder it all up again.

Takes a lot less time than cutting all those individual lengths of wire.

And I will take care it does not happen again, it occurred with a pre modded unit I was applying an extra mod to. If you do this in future, my advice with premodded units is to check the strength of the cable and if it seems like it might eventually break from the board, use serious care with this because refitting ribbon cable is bloody annoying and time consuming for something that seems so simple.

All credit to the PCE it seems no matter what you cut on the board it won't perma damage any ICs, if you had any such damage to oh, say, a Saturn it'd fry it in some respect. Such a badly put together console.

I even had a PCE with snapped off RGB pins that was repairable, I took a knife and scored down through the casing of the chip (you can use a dremel for this but I'd say you risk cutting down through the metal pins furthur) to expose more metal, soldered to that and the damn thing worked. I love the PCE.
https://retro-access.com/ - Modded consoles and SCART cables for retro consoles and computers. We ship worldwide.

pceslayer

Thanks to papa_november I was able to obtain a gear for the CDROM unit.

Got it installed and it still doesn't work! WTF!

Does anyone know if there is a capacitor issue with these old drives?

Things Ive tried:

Replaced the Gear
Replaced laser and tweaked it(tried 3 lasers)
Swapped out the motor
Swapped out the stop switch

Its starting to frustrate me...

TheMilford

Quote from: pceslayer on 04/01/2009, 10:50 AMThanks to papa_november I was able to obtain a gear for the CDROM unit.

Got it installed and it still doesn't work! WTF!

Does anyone know if there is a capacitor issue with these old drives?

Things Ive tried:

Replaced the Gear
Replaced laser and tweaked it(tried 3 lasers)
Swapped out the motor
Swapped out the stop switch

Its starting to frustrate me...
Have you just tried re-flowing the board?

pceslayer

Quote from: TheMilford on 04/01/2009, 12:57 PMHave you just tried re-flowing the board?
You mean re-heat the already existing solder points?

TheMilford

Quote from: pceslayer on 04/01/2009, 07:03 PM
Quote from: TheMilford on 04/01/2009, 12:57 PMHave you just tried re-flowing the board?
You mean re-heat the already existing solder points?
yes... but use some fresh well-flowing solder and add a tiny bit and re-flow the entire board. this is the the first thing any real tech will tell you to try. "cold"solder-joints are hard to track down so it's best to weed them out right at the beginning.

papa_november

Have the symptoms changed at all?

Make absolutely sure your CDs are good. It's always handy to have one original (as in, not burned) CD game (no matter how shitty) laying around for testing. I learned that the hard way a few months back.

pceslayer

Ive only tried originals... This CDROM unit is going to be the death of me  :x



In the meantime I got a broken PCE Duo off ebay for $73 shipped(damn shipping was $48). Auction said it was junk and the laser was bad.

Noticed the CD spindle was pushed down below the laser assembly, so I pulled it off and re-seated it and now it works. It still doesn't read discs 100% though... It seems to have trouble reading audio tracks past a certain point on a disc.

In the end it took longer to get the damn screws off the case then it did to get it working.

papa_november

That's pretty odd. Are you sure the drive mechanism is clean?

Hose off the motherboard and replace the SMT capacitors with tantalums until stuff starts working.

Duo_R

how about replacing the laser unit assembly on the broken duo.
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pceslayer

Quote from: Duo_R on 04/05/2009, 04:57 PMhow about replacing the laser unit assembly on the broken duo.
Well after messing around with it for a while this morning... It only has the issue with original pressed discs :-k

I burned a few backups of the same game and no issue....

the original discs are flawless, not even a speck of dust on them.

Does it to Audio CD's too... where a backup of the exact same disc plays flawlessly.

papa_november

I can safely say that nobody has ever seen this problem before. Usually the reverse happens.

Duo_R

sounds like the laser pot got messed with. I have heard of this happening on other systems like PS1.
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pceslayer

Quote from: Duo_R on 04/06/2009, 08:16 AMsounds like the laser pot got messed with. I have heard of this happening on other systems like PS1.
As far as I can tell the console had never been opened.

Ah well, I can live with a duo that only reads CDR's... It'll keep me from scratching up my originals  :-"

Duo_R

Ask Snow Kitty, he seams to know a little on the laser adjustments. DO NOT attempt to do it without getting some knowledge. But I think ur laser just needs adjusting.
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