Messages

[Console Repair/Mod Center / Re: Trying to recover a Failed PCEngine GT recap]

Thanks for that Keith.  The customer is purchasing a AV output kit and screen so going to get rid of the OG screen for good.

[Console Repair/Mod Center / Re: Trying to recover a Failed PCEngine GT recap]

As stated when given to me only 2 had been replaced.  I have completed all of them now.  I have recapped 6 units so far so I am not totally new to this

[Console Repair/Mod Center / Trying to recover a Failed PCEngine GT recap]

Hey everyone, I have been given a PC Engine GT to complete a failed recap.  Only 2 caps had been attempted and both had pads ripped off.  I have replaced all caps now and traced the bad traces and made sure the caps are in place.

I now get perfect sound but only backlite black screen. I checked the 4.7uf cap was installed correct and it was.  I did notice a missing resistor which I have a picture of.  The other 2 resistors next to it are 830ohm so I added one I had laying around but no display.

Any advice on what could have happened ?  Before the first attempt the user mentioned he did have display but very dim.

Thanks

[Console Repair/Mod Center / Re: Replacement CD tray sensor switch - PCEngine DUO - Where to get?]

You could also just bridge the solder points so it always thinks the tray is closed.

True but I want this thing to be nice and complete.  For $6 it is worth it I think to have it working as expected.

[Console Repair/Mod Center / Re: Replacement CD tray sensor switch - PCEngine DUO - Where to get?]

http://gamedoctorhk.com/index.php?main_page=product_info&cPath=72_21_123&products_id=2036

Perfect!! thanks so much for that one.  Order and paid for

[Console Repair/Mod Center / Replacement CD tray sensor switch - PCEngine DUO - Where to get?]

Hey guys,
I have been having problems with my duo and it thinking the CD lid is up when it is closed.
I checked and the switch looks like it been squashed at some point and does not spring back properly.
Anyone know what sort of a replacement I need for this?  Or what the name of the switch I need to be looking for?  I am sure someone in China has this type of switch somewhere but not sure what it would be called.
Thanks!

[Console Repair/Mod Center / Re: TE Sound Fix Really Abnormal Situation]

I think you also need to do the bottom 2 pins of the row of 3 pins as the switch controls those also

[Console Repair/Mod Center / REPAIR GUIDE - TurboExpress: Sound Fix]

Thanks for that.  Well if anyone has something please let me know.  I will keep an eye out for one.  I found one for sale on a retro website but I think the shipping for such a little thing will be a killer to Australia.

[Console Repair/Mod Center / Re: REPAIR GUIDE - TurboExpress: Sound Fix]

the speaker hooks to the headset jack directly
the jack jumpers the speaker on when no jack inserted
the jack could be just dirty

Thanks for that.  Can I possibly put a solder jumper to force the external speaker to work?  Just to confirm it is the headphone jack.

EDIT:
I bridged the points that are shown in page 1 of this thread and now I can get audio out of the speaker!!  So looks like it could be the headphone jack connector.  Any tips on cleaning that up or even a replacement that can be used?

EDIT once again:
More investigation has shown that the little gate inside the headphone jack is broken.  Now comes the tricky part.  Is there a replacement for one of these?  I have external audio now at least but would be good to get it back to fully working.

[Console Repair/Mod Center / Re: REPAIR GUIDE - TurboExpress: Sound Fix]

Hi thesteve,
I have just recapped my friends one but still no audio at all from internal speaker.  I do get audio from the headphones.  There was some damage to the tracks on one of the caps.  Its the 100uf right next to headphone jack.
I traced the positive to pin 4 of a chip on the backside of the board and the negative just went to negative.
Any idea's about why no audio would be coming out or if there is something else I can try?

[Console Repair/Mod Center / Re: Help! Need to know the value of missing resister in PC Engine GT]

It ok.  I opened up my personal unit which I forgo about and checked.  It was a 103 which is 10k
Thanks anyway guys

[Console Repair/Mod Center / Help! Need to know the value of missing resister in PC Engine GT]

Hey guys,
I am working on a a PCEngine GT to replace the caps and I had the rework station fan speed too high.  Now a resister went flying off the board and now I have no idea what the value was.
The resister is R513.  I have tried to find hires pics of the board but have not had any luck.
Here is a picture of the open board.
If someone has one open or a list of the resisters that can let me know that would be awesome

[Buy/Sell/Trade / WTB : PC Engine GT or Turbo Express - Screen can be broken]

Hey guys,
Looking for a PC Engine GT to have a play with.  Not fussed if the screen has lines etc as I am looking to do a screen replacement.
Looking for the cheapest option as this is purely for me to play.  If anyone has anything they are looking to get rid of PM

Thanks!

[Buy/Sell/Trade / WTB : PC Engine GT or Turbo Express - Screen can be broken]

Hey guys,
Looking for a PC Engine GT to have a play with.  Not fussed if the screen has lines etc as I am looking to do a screen replacement.
Looking for the cheapest option as this is purely for me to play.  If anyone has anything they are looking to get rid of PM

Thanks!


Just realised I placed this in the wrong section.  Mods can you please move to the NEC buy sell section?

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

Another one brought back from the scrap heap.  Well done on the find!!

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

Yeap that looks definetly like the memory modules issue to me.  I would be replacing those.

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

May I ask where you bough the chips from?I cannot seem to find them from anywhere that doesn't require an order of like 50 or more.

http://www.ebay.com.au/itm/170895817675?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
This is the guy i brought them off

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

Finally got around to getting some memory chips.  Sourced them from Germany

Started with the first one.  one leg was stuck and ripped the pad up so had to trace back to a point to solder a wire to it.


Decided to try it before changing the other one.  Success!!!


Thanks to all for the advice guys.  Another DUO saved from the scrap heap.

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

Looks like mine are stuffed. 
Found the culprits on the underside of the motherboard.  Here are some pic of them.  i do not have a logic probe but I traced every single pin on them and they all seem fine.
Touching the pins cause the image to change somewhat but is still not good so I suspect these are fried.  Anyone got a couple of these from a junk board i am can grab ??

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

Will need to check when i get home.  i found this thread
https://www.pcengine-fx.com/forums/index.php?topic=9946.0
On the schematic the IC904 and 905 are labeled with 20256 which I have found a few on the eBay.  Will confirm 100% but I want to make sure that this could possibly be the problem I have

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

I have no idea.  I would suspect yes but really cannot answer that one

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

Thanks for that Steve.  So do you suspect it could be IC904 and IC9045 VRAM causing the issues?

[Console Repair/Mod Center / Re: Retr0Bright a PCEngine - See the results]

Sorry.  I did make a typo and would not use bleach.  I think I got thrown with an earlier post using bleach to clean.

[Console Repair/Mod Center / Re: Retr0Bright a PCEngine - See the results]

Easy mamejay, Arkhan maybe be strongly opinionated, but hes a good guy. He was not personally attacking you either so try not to make it personal. Nice work on the retrobright. Its the bromide in the plastic, a fire retardant, that makes it yellow. Supposedly eventually the amount of bromide in the plastic will get used up and stop yellowing. Keep it up.

Fair enough.

@ Arkhan
You method is the first I have heard of it.  I will give it a try but its just strange that no where on the web do they talk about using just straight bleach and sunlight.  I thought the retro guys wouldbe all over this.  Anyway
I will suck it and see

[Console Repair/Mod Center / Re: Retr0Bright a PCEngine - See the results]

"Is RetroBright better than bleaching?"


Its the same thing.  Retrobright is just the overly engineered version with a bunch of nonsense additives that do nothing.


You'd have gotten better results with a better UV light.   Go get one designed for tropical lizards at a pet store.  You've likely got that bulb up so far it's barely delivering the waves to the plastic.


The effective range is like 12".



You should have just bought clear peroxide developer.  The liquid.  not the cream.

Take the PCE, stick it in a small clear container, fill the container with the liquid... stick it in real sunlight.


You'll have it back to new status in like 2 hours or less.

The PCE is so small you won't need a large container.  As a result you will need less liquid.



I used to bleach C64s in marathon sessions during the summer.   I know what I am talking about.


I swear I've posted this on this forum at least 3 times now.

What a happy boy you are.  Thanks for the advice.  Maybe you need to work on your delivery.
I have been warned in the past about using bleach.  It works on some things but not everything.  As for the light it is no more than 12" above the plastics.  Also it is winter here in Australia and not much sun to go around.  You make it hard for people to take you seriously when you rant like that.  No wonder you have posted about your method 3 times and no one has taken any notice

[Console Repair/Mod Center / Re: Retr0Bright a PCEngine - See the results]

I think it is.  That console in the link was no way near as bad as my console.
I am going to try out the proper retrobright where you mix peroxide and a few other things and see how it goes

[Console Repair/Mod Center / Retr0Bright a PCEngine - See the results]

OK.  I decided to give this whole biso a go.
I opted for the easy single bottle of creme peroxide solution.

I used a black light I have had for ages.  Not sure if it is actually UV light but decided to give it a go
I created my retrobright chamber of light (cardboard box and al foil) and got cracking.






Before I started

First treatment picture again

Here is after the second treatment

Third Treatment.  not sure if the pictures show much difference but it has gotten rid of some very minor blemishes now

[Console Repair/Mod Center / Re: Graphics Glitch - DUO]

I think the chip that is causing the issues is a Sanyo lc3564pm-10L.
This is the VRAM for the PC Engine.
Now all I need to to try and source out is a working chip from somewhere to test this.  Can anyone on the forum help?

[Console Repair/Mod Center / Graphics Glitch - DUO]

Hey Guys,

I finally decided to try and tackle a junk DUO I purchased some time back.
Basically the console works perfectly except for the graphics.
i get constant graphics glitches on any screen.  This happens even on first start up and the Super CD rom menu so I suspect it is something to do with the video ram.
Can anyone help me with this ?  i am pretty good at soldering so i could replace most of the chips on the motherboard.  Its just trying to identify which one is the correct one to work on.
i would prefer to fix it than junk it as I hate to see retro console get trashed.
Here are some pics of the issue and the motherboard.  Any help will be greatly appreciated

[Console Repair/Mod Center / Re: Region Lock disable - Is a switch required?]

Cool.  Will replace the SPDT with a DPDT switch and add the pin 29 and GND to the other legs of the US/JAP of the switch.

[Console Repair/Mod Center / Region Lock disable - Is a switch required?]

Hey guys,

I did a region mod on a JAP supergfx for a mate of mine.  He got a pre-made PCB.
Got it installed and its working great.  I disabled the lockout pin by grounding pin 29.

My mate is insisting that there needs to be a switch to enable the lockout for some of the JAP games.
Is this correct?  I cannot find any information about and all my tests at home with about 20 hu-cards worked perfectly.
If it is correct does anyone have a list of games that require it?
Thanks

[Console Repair/Mod Center / Re: PC Engine DUO graphics issues]

Just got confirmation from the seller.  Even when using the CD it has the same graphics issues so I am starting to think more on the lines of a board fault.

Hopefully its only CAP issues which can be repaired.

[Console Repair/Mod Center / Re: PC Engine DUO graphics issues]

Thanks guys.  That's what I suspected. Just going by some of the weird graphics I get on my PCEngine when the cart is not inserted correctly makes me think it is just contacts.
Thankfully changing the caps on these is nice and easy as there is heaps of room in these babies.

[Console Repair/Mod Center / PC Engine DUO graphics issues]

Hey guys,

Wondering if anyone can tell me what could be causing this issue with a DUO?
I have not received the item and I am buying as faulty.
Please give me your opinions on what could be causing the graphics problems.
Thanks

[Buy/Sell/Trade / Re: NOW WITH PICS! Bartre's FS thread!]

PM sent regarding Sega32x

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

Thanks for that Snow Crash but that is only a crystal.  Another member on the forum has kindly found me a couple from some junk PCE's that he has.
I LOVE THIS SITE!!

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

Excellent.  I am killing myself to find a oscillator to put into the one I removed it from.  Damn impossible to find.

[Buy/Sell/Trade / PC Engine 21.4772MHz crystal oscillator]

Hey guys,

Doing a repair on a PC Engine and need to get my hands on a 21.4772MHz crystal oscillator.
If anyone has one from a junk console or something like that I would be interested.
Please pm me if you have anything.
Thanks

[Buy/Sell/Trade / WTB crystal oscillator 21.4772MHz]

Hey guys,

Doing a repair on a PC Engine and need to get my hands on a 21.4772MHz crystal oscillator.
If anyone has one from a junk console or something like that I would be interested.
Please pm me if you have anything.
Thanks

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

mine board is slightly different.  I just know from doing Sega Mega Drive crystal oscillator mods that you need to cut the trace if you do not remove the crystal oscillator,   That is the rectangular box thing.
Mine was already removed and the additional board output was being fed to the where the oscillator was.

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

Let me know how you go.
If you still have the original crystal installed I am a little concerned that they may have cut a trace somewhere on your board.  Mine was totally removed so no traces were cut.
Just check yours for cut traces.  If you look at the crystal onboard there is a squared off corner.  The opposite diagonal corner is the MHz output.  Follow that pins trace and see if they broke it somewhere.

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

I just used regular resisters and trimmed the legs and did some bending of them to make them as flush as possible.
Be careful as the track on the board can lift really easily

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

OK.  I have worked it all out now.
Here are the exact values.
R137 - 6.2k
R138 - 8.2k
R141 - 26.7k
C137 - 220uf capacitor
I used whatever resistors I had available.  6.7k for the first, 8.1k for the second and 26.8k for the last.
For C137 I just used a 220uf electrolytic capacitor.  I fired up the console without the cap and did a voltage check on C137 to see the polarity of the points.  Then you attach positive to positive and neg to neg.
Got nice colour now and the games are looking correct.

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

We have a problem.
I did some more testing and the colours are a bit off.  I need to play around with the resistance values a bit more.  Looks like greens are not coming through 100%.
I will let you know the values once I work them out

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

OK.  I have done some testing and reversed my PCengin back to NTSC.
I ripped out a crystal from a working PCengine and popped that in.
I then replaced the resisters with the follow.
R137 - 6.7k
R138 - 6.7k
R141 - 13.2k
C137 - Bridged points.
Anyway its working fine.
I had a resister on C137 but i got a shacky picture at the top.  once I bridged the points it was fine and stable.
So now just need to source out a 21.4772MHz crystal oscillator and I will be set.
Let me know if you need a hand.

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

I will get a picture taken and also get all the values of the resisters.  We will need to work out what that C137 is as I am pretty sure its a CAP.

[Console Repair/Mod Center / Re: PCE old Pal mod reversal.]

I have tested the c137 and it gives me resistance and I am suspecting it's not a cap.  That is the only thing I cannot determine 100% from my pal modded board.  If anyone has info or a schematic this would make the reversal easy

[Console Repair/Mod Center / Re: Problem with AV Out PCEngine - strange daughter board]

Yeah mine is the same.  Mine has has the original crystal removed and a few resistors.  I have used my multimeter on an unmodded board and it looks like all removed components are just resistors.  I will make a list of the removed components and see if we can reverse this mod.

[Console Repair/Mod Center / Re: Problem with AV Out PCEngine - strange daughter board]

That majority of parts that were removed I can get.  Its just a couple of caps which I do not know the vales of.  Anyone have schematics for a PCE where I can get the values?

[Console Repair/Mod Center / Re: Problem with AV Out PCEngine - strange daughter board]

There must be a way to feed back in a NTSC signal crystal as the solder points are all there.  Does anyone have schematics for the PC Engine?