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[Console Repair/Mod Center / White PCE only giving a screen.]

Hi folks, I thought I'd pop on here to seek some help to rescue a poor PCE.

I offered to try and do a freebie fix a PCE for another chap who said he's getting nothing from it, and so far I'm not getting far either.  I opened it up to check the fuse and found it's blown but has also been bypassed 

I removed the bridge and the fuse, to make life easier I removed the voltage regulator and the heatsink.  So, I didn't have a 1.5a fuse to pop in there but figured I'd get away with a 1.5a to use as testing and fit the proper one if I get it working.  Whilst I had the voltage regulator off, I thought I may as well pop a known good one in there.  I checked for short circuits on the input and output of the voltage regulator and it was good.

I measured some voltages and all seemed good before and after the fuse and going in and out of the voltage regulator, so I risked it and powered it on with no card in it and received a white screen, TV shows it's receiving a signal though and this is what my working PCE does with also.  I pop a known good game in it and I still only get a white screen.  Googling shows that it could be dirty contacts for the hucard slot.

I cleaned the card slot (it was filthy), I also inserted the card and pull it back a bit to try that, still white screen.  I noticed if I pull the card out ever so slightly I can check connectivity between the contacts on the card and the pins coming out of the back of the card slot, they all tested fine.

I also reflowed the solder on the connections for the flat ribbon cables for the hucard daughter board.  I checked connectivity for the ribbon cables and they were good, still get a white screen though.

I don't have a logic probe, so am a bit limited on what I can test.  I did read that some people have to replace H6270, so I reflowed the solder on it, then thought I may as well reflow the solder on the other chips in there at the same time.

It looks like an RGB mod had been attempted at some point to this cute little guy, the solder points for the pins on the Exp port for RGB look a bit worse for wear, I reflowed the solder on them.  The RF unit had also been removed at some point I think.

There was some thick black gunk over some of the traces on the underside of the board near the RF unit, I cleaned it off hoping to see some badly repaired traces there, but nope, they are good.

I replace the Cap that's on the hucard board (I found one the right spec and figured it may help with the problem being hucard related), I visually inspect the other caps and can't see anything wrong.  I don't know how to test caps though and I don't have spares to replace all of them.

I could take the H6270 off and check for dodgy traces under it, and the other chips.  I guess I could swap them out with ones from my PCE to check each of them.

Can anyone offer any advice?  This guys already done a cracking job on de-yellowing it, it would be ace to get it up and running again!

Thanks
Pete

[Console Repair/Mod Center / White PCE, only displays a white screen?]

Hi everyone

I recently got my first PC Engine last week.  What a beautiful little machine!  I've got a couple of games sat here waiting to play on it - Pac Land and Shinobi in particilar.

The machine came to me with the RF unit in place, I had no way of testing it so had to go ahead and RGB mod it.  I tried it tapping the RGB signals from both the ext bus port and from the chip but all I get on the screen is white, nothing else.

I know that the TV switches to 60hz mode, but that's as far as it gets.  I have cleaned the contacts on all my games, and on the console itself.  I even put a thin business card in the cart slot, then put the hucard in ontop of that - hoping the business card would push the hucard onto the contacts.

It seems no matter what I do, I'm stuck with a white screen - it's been confirmed to me elsewhere that a white screen is what you get if no card is inserted, but could there also be a problem elsewhere that I could look at?

Any help appreciated.

Ta
Pete