Messages

[Console Repair/Mod Center / PC Engine GT - Contrast Issue]

Hi Folks,

I'm trying to troubleshoot a contrast issue on a PC Engine GT.

The issue is that the contrast/brightness will not go up to its maximum, it seems to get to a certain point and then turning the variable resistor doesn't increase the contrast any further so the screen is slightly too dark - a PC Engine GT without this issue will go as far up as pure white screen.

The PCE GT has all of the SMT capacitors replaced, this hasn't solved the contrast issue.

I've traced the tracks that supply the contrast variable resistor and I can't seem to find anything interesting.. I measured the voltages compared to a PCE GT without this issue and the PCE GT without the issue seems to have slightly higher voltages supplying the contrast variable resistor.

I've tried the screen from another PCE GT and the issue still remains, so it is definitely a fault on the PCE GT mainboard.

I have a few pictures, the contrast variable resistor is the part marked C701, on the right hand side of most of the pictures.

I was just wondering if anyone else had the same issue, and how they managed to fix it, I did do a search of the forum but couldn't find anything specifically relating to this contrast issue. Or if anyone has some schematics, or can explain where and how the contrast signal is generated on the mainboard, that would really help!

[Console Repair/Mod Center / Re: Breaking News! TURBOEXPRESS / PC ENGINE GT VIDEO FIX!]

I actually posted the same information in October of last year, but didn't create a breaking news thread 

PC Engine GT Screen Fix ?

[Console Repair/Mod Center / Re: TurboExpress / GT White LED Mod?]

Interesting idea - how much difference would it make on run time; 20 minutes wouldn't really be worth the effort, but 2 hours would be awesome.  A LED mod and/or a replacement LCD would be mighty tempting upgrade for the ol' Express.

Hmmm.. I'm not entirely sure.

Whats the normal running time of a TE/GT? I suppose it depends on the batteries too.

I think that the (CCFL?) inside, is probably fairly inefficient, since it was produced so long ago..

A total LCD replacement would make the darned thing fully worthwhile.

Is that really possible?

I have the feeling a replacement (with the additional circuitry that these things have..) wouldn't fit in the TE/GT case..

[Console Repair/Mod Center / TurboExpress / GT White LED Mod?]

Has anyone ever done, or contemplated doing, a TurboExpress / GT White LED Mod?

i.e. replace the (CCFL?) which illuminates the screen, with some white LEDs, a la Ben Heck portable TV White LED mod..

Why?? for battery consumption reasons..

Thoughts, issues...?

[Buy/Sell/Trade / WTD: PC Engine Duo-R **Instruction Manual**]

Wanted:

Original PC Engine Duo-R Instruction Manual.

Must be in good to excellent condition. Will pay a fair price.

Seller must be able to ship to the UK.

Thanks!

[Console Repair/Mod Center / Re: Why do CD-R's Damage the Duo Lens?]

It's an old rumour spread by people that don't like "backups" the laser has to work a little harder to read a CD-R since the pits aren't as defined as a factory-written CD, but people make out as if using a few CD-R's will kill a game console laser.. 

[Console Repair/Mod Center / Re: When good Duo's get bad...(also a fixed arcade stick)]

Try leaving the system powered on for 10-15 minutes then attempt to load a CD.

If it works then, you need to replace a lot of the surface mount capacitors inside the Duo..

[Console Repair/Mod Center / Re: TURBO DUO SOUND FIX!! (56k beware)]

After a bit more buggering about I've found that the sound actually works perfectly. The reason it wasn't working was because whilst I replaced the caps, I replaced the AV socket for an 8 pin version. It seems that the pins for audio on the old AV cable dont connect properly.

So its working beautifully actually! Sweet 

[Buy/Sell/Trade / Re: Drop Off? Creepy....]

Weird as hell. Shes selling well-worn nylons now as well as some SNES stuff.

I can't view the "adult listings" because im blocked (outside of US)

*shudders* 

[Console Repair/Mod Center / Re: PCE Duo / Duo-R DC connectors]

Hey turbo D, I don't understand? I never knew that crimp connectors are available? Certainly all of the connectors in my catalogues are to be soldered only.. the inside has a cable grip and it holds it extremely sturdily, you couldn't really pull the wires out from where they are soldered on, most of the connectors are really high quality..

[Console Repair/Mod Center / Re: TURBO DUO SOUND FIX!! (56k beware)]

Hey, I made a thread because I solved my PCE Duo's noisy laser problem, and the problem it had where it took a long time to "warm up" before reading CDs.

However in the process the sound through the TV speakers has been knocked out, for HuCards, Music CDs and CD games..

However the audio from the headphone port is perfect.

There was one extra cap on my revision of PCB that wasn't on the total capacitor replacement chart, so I guessed the value (22uF?) based on the values of those caps around it, however its not really that close to the main audio amp.

Anyone any ideas how I can diagnose the problem and regain the audio from the speakers?

All I changed was all the caps.. and 95% sure they are all correct values and orientation... UNLESS, I needed higher voltage ratings on the caps? anyone know what the original caps that surround the main amp are rated at?

[Console Repair/Mod Center / Re: PCE Duo Grunty/Wheezy Laser Fix and Other Problems Fix!]

Hey spenoza, well it will be some time yet, but I'll let you know if I get one fixed.. it would probably seem expensive though, since £1 GBP (British Pound) is about $2 US at the moment..

I actually tried the Duo again and because it was late at night after I finished replacing the caps, I didn't have the audio turned up, and in fact where the audio worked before, it now doesn't seem to work, but the headphone port has great audio! dam!

Gotta fix this, heh.

[Console Repair/Mod Center / PCE Duo Grunty/Wheezy Laser Fix and Other Problems Fix!]

Hey dudes,

Got a PCE Duo off the 'bay, all boxed and nice, seller said it had laser problem and needed replacing. I replaced the laser and it still wouldn't read games.

I noticed from the topics on here that people tend to have problems with the audio, and those damn surface mount capacitors again..

Anyway, sometimes I think the laser problem can just be a dropped down spindle, in fact a Duo-R I have here I pulled the spindle off with a pair of pliers, and reseated it and it works like a charm (this was another unit sold with a 'faulty laser' when in fact the problem was just that the spindle had dropped down and therefore the laser was too far from the disc to read CDs)

Anyway, I digress.

By pure chance, I found that after leaving the PCE Duo powered up for around 10 minutes, when putting a game in then and trying to play, it would in fact load up and play nicely!

The laser was making a noise as it was moving though like a grunty wheezy whirry sound.

Anyway, I thought, its those damn surface mount capacitors again! I had a look and yes, in fact nearly all on the board were in various stages of leaking, and of course those 7805 voltage regulators get damn hot, so I decided to follow the capacitor chart posted here and replace them all.

I removed all the old surface mount capacitors and cleaned up all the leaked electrolyte, and then fitted all radial capacitors.

I had to make the leads on the ones near the front of the system pretty short, otherwise the case doesn't close.

Anyway, I tried now and you can load games immediately after turning on, and the grunting, wheezing, whirring is gone.. silky smooth motor operation, works like an absolute charm!

The next thing I am going to do is a neat solution to resolve the HEAT problem. Then I'll probably give the system the usual RGB amplifier and region mods. Oh and I fitted a blue LED as well, which looks sweet as.

Then after that, I want to tackle the CDROM2 / IFU-30 problems, as I have about 5 briefcase setups here 4 which were given for free, and one which I purchased for peanuts! 

[Console Repair/Mod Center / Re: PCE Duo / Duo-R DC connectors]

In case anyone is interested I did find out that;

PC Engine DUO DC Connector is 3.0mm
PC Engine Duo-R/RX DC Connector is 1.7mm, Pin Diameter 4.0mm, Pin Length 10mm and it has to have a yellow tip which is called "ECJ" its a Japanese type.

Might be useful to someone. The reason I wanted to find these out is because I can cut the tip off a 9V 1A UK Power Supply and solder on one of these solderable connectors, and volia I have a power supply that would be otherwise impossible/expensive to obtain over here, which runs off UK voltage so no stepdown adapter required.. 

[Console Repair/Mod Center / Re: PC Engine GT Screen Fix ?]

Hey D-Lite

I don't know which specific cap, I just replaced them all, there's really not that many, and pretty much all of them were in various stages of leaking, replace them all and it should work 100% 

[Console Repair/Mod Center / Re: PC Engine GT Screen Fix ?]

I've solved the issue now. PC Engine GT with an apparent "faulty" screen, is now working like a charm (and with loud sound and all!).

Firstly I tested the screen in another fully working GT, the screen worked great - tells me the issue is something other than the screen, i.e. component(s) on the GT's main PCB.

I checked the voltages going to the screen with my multimeter, and compared those to the voltages going to the screen with the GT that was fully working - interesting, I noticed one MAJOR variation in voltage - perhaps the lower voltage was not enough to drive screen output?

I tried to follow the trace, but it proved quite difficult and I lost it.

So then I started looking at the capacitors, thinking a lower voltage was probably a dodgy capacitor. I noticed that on all of the capacitors, where the silver legs are, they were not silver/metal coloured but in fact yellow/brown/dull. I removed one capacitor to look underneath. A brown mess of dried electrolyte!

Every surface mount capacitor on the PCE GT PCB had leaked!

So I went and ordered replacements, getting surface mount where possible, and a couple of strange values/max voltages were replaced with microminiature radial electrolytics.

After reassembling everything the unit now has perfect, loud sound, and a great display (bar one dead pixel!)

So I think the general rule now is, that if you have either of the sound/screen problems, replace all surface mount capacitors (except for the three, large, yellow nichion 16v 100uF capacitors, as I removed one of those and it was nice and wet inside!) all of the smaller surface mounts were BAD!

Even my GT that is working perfectly, has this yellow/brown/dull look to the leads, which suggests the capacitors in that unit have all leaked too!

So glad I managed to solve the problem 

[Console Repair/Mod Center / Re: What's wrong with my TurboDuo?]

Is the spindle properly seated and not dropped down? The bottom of the plastic spindle should be just above the top of the plastic pickup cover.

[Console Repair/Mod Center / Re: PC Engine GT Screen Fix ?]

Hey Keranu,

Here's a pic with regards to the easy soundfix.

What you need to do is desolder the black and white wires from the speaker.
Unplug the connector they go to.

Solder two new wires on, of a longer length, make them fairly long, you can always reduce their length later.

The wire you now have soldered to where the black wire was, solders somewhere to ground (in the case of this PCE GT, it was soldered to the metal shield, its the black arrow and circle in the picture.

The wire you now have soldered to where the white wire was, solders to the leg of the chip which is just poking out from under the metal shield, its the white arrow and circle in the picture.

And thats it. Obviously its probably only a fix for the speaker, not the headphones too. And replacing the original caps is probably still the best way to fix, but this seems to be an easy fix for the less nimble  sorry about the poor pic, if you need any clarification just ask me.

I think im also quite close to fixing the SCREEN issue!

/gtexpresseasysoundfixgh8.jpg

[Console Repair/Mod Center / Re: Region Mod PCBs available: now with silk screen and solder mask!]

So does Markus Brandel's region mod not fit in a GT? Looks like there's quite a bit of space at the back, where the HuCard slot is.. I haven't tried it yet but I have a beat up GT I got for cheap.. maybe... 

[Console Repair/Mod Center / PC Engine GT Screen Fix ?]

Hey guys,

I have done the GT sound fix, and im just wondering if anyone has cracked the screen fix yet?

The GT I am trying to fix, the backlight works fine, if I switch the screen with a working unit, the screen works, if I try a working screen from another unit on the one with the screen that doesn't work, it doesn't work.

So in short, theres something on the mainboard of the GT which is making the picture not appear..

I did quite a bit of searching on the forum and the 'net, and didn't come up with much.

I found a post by "gamedoctorhk" here: https://www.pcengine-fx.com/forums/index.php?msg=16768

Where he says that its simple to fix the screen, you need to replace a part, but he doesn't say which part. I looked at his other posts and it says he is gamedoctorhk on ebay, I messaged him and he tells me that he doesn't know which part. So I direct him to this post and he says its not him, which is weird since he advertises the same items here, has the same email address posted here, and the same username, so I think he's unwilling to tell me which part to replace which is disappointing..

I'm guessing it's a capacitor but I was just wondering if anyone knows which one in particular?

Oh, and the GT I need to fix, appears to have a sound fix already done on it, but instead of the capacitors being replaced for the sound, it seems that the speaker wires have been disconnected from the board with the controls on, one wire has been soldered to the metal shield that covers some of the circuitry on the mainboard, and the other wire has been soldered directly to the leg of a chip which just pokes out from under the metal shield, so I suppose this is a fix with no surface mount capacitor removal / replacement necessary? which is nice.. I can post a couple of pics up if anyone is interested?

Anyway thanks in advance, hopefully can figure out which cap to replace and get this GT screen issue sorted 

[Console Repair/Mod Center / PCE Duo / Duo-R DC connectors]

Hello,

Would anyone happen to know the specs, i.e. measurements etc of the PC Engine Duo, and PC Engine Duo-R DC power connectors? I thought that the Duo-R was the same type as Megadrive II, but that type of DC plug (2.1mm?) doesn't fit. The original Duo has a very wide connector.

Cheers! 

[Off-Topic / Re: SCART]

SCART is used in the UK, Europe and parts of Australia etc.

Its basically a 21 pin connector which provides lots of AV functionality in the one connector. So you get RGB, Composite Video, Stereo Audio etc.

An arcade monitor uses RGB, all televisions use RGB, the cathode ray tube in a TV fires electrons at the phosphor coated screen and the combination of Red, Green and Blue determines the colour of the pixel on the screen.

An arcade PCB directly outputs RGB video, so that just goes straight to the monitor. SCART is not used.

However you can wire up a PCB to a SCART plug and use on a television with a SCART socket.

In the US you won't find televisions with SCART sockets as for some reason they decided composite and s-video were good enough.

You can find an old Commodore monitor that has analogue RGB via a 9 pin D socket, or perhaps a round DIN connector. Then its a case of wiring up a custom cable from the arcade PCB to Commodore monitor.. or find an imported television..

[Buy/Sell/Trade / Re: I need a laser replacement for my Duo]

I have one that you may buy. I'm in the UK so shipping will be cheap.. Please PM me..

[Console Repair/Mod Center / Re: Nintendo NES pad on a PCE/TG16 ?]

The guide could be written better, but excellent, thank you very much 

I'll let you know how I get on with it..

[Console Repair/Mod Center / Re: Nintendo NES pad on a PCE/TG16 ?]

Crap, did my PM not reach you, chaoticjelly? Not that my PM was very informative to begin with since I don't know of that site, but I'm sorry if it didn't get to you. Anyways, could you post a link the thread where I mentioned that, chaoticjelly? I don't quite remember my post about that.

Nope.. got lost in the vastness of the Interweb I think 

The thread where you mentioned it is here;

https://www.pcengine-fx.com/forums/index.php?topic=1747.0

Cheers

[Console Repair/Mod Center / Re: Nintendo NES pad on a PCE/TG16 ?]

I thought maybe I was too n00b on the forum for a reply 

I think a NES pad would handle quite well, and of course it's 2 buttons like the PCE/TG16 controller.. 

[Console Repair/Mod Center / Nintendo NES pad on a PCE/TG16 ?]

Hi Folks!

I was doing a forum search and I came across a thread which Keranu posted in saying that there was a site where it describes how to connect a NES controller to a PC Engine/Turbografx 16. I've tried PM'ing Keranu but no response yet.. this was a few days ago.

Does anyone else have this link? I've done several google searches and come up with zippity squat, zilch, nada.

There is a plentiful supply of NES controllers at a local store but actual PC Engine/Turbografx 16 controllers are like gold dust, so this guide would be extremely useful for me..

Many thanks for your time,
CJ.

[Console Repair/Mod Center / Re: PC Engine AV mod]

Stuey told me about this thread so I have registered, apologies for not introducing myself first, I am fairly active on some other forums which I wont mention since im not sure if its against your board rules yet. I have lurked here a bit too.

I am the person who modded Stueys PC Engine as shown above for RGB output. I think the original poster may be wanting RGB output instead of A/V output, but yes, you could call the socket an "A/V socket" that outputs RGB..

I modded Stueys by taking out the old RF unit and trying to neatly enlarge the hole to fit the new DIN socket.

It would of been possible if it were a standalone PC Engine to have a captive cable coming out of the rear i.e. no socket, just a cable coming out secured by a grommet, but since he wanted to use it with an IFU-30 and CD-ROM unit that wasnt an option.

Anyway if anyone wants to get in touch I can provide plenty of feedback and references with regards to my modding skills, all happy people of course, just send me a PM and I can provide all the necessary info.

Ive only got into PC Engine recently, ive played "teh romz" some time ago on my GP32, and I really like the system and games. Im a big collector of Sega and Nintendo, from the UK, North-West (Lancashire)

Anyway peace out, James.