Duo Repair Gone Bad, looking for suggestions

[poponon]

So where to start... for some time now I've become extremely interested in the pc engine. Being a huge fan of the other 4th generation console, the huge amount of exclusive games on the pc engine really drew my interest. So a few months ago I ordered a duo from japan and have been anxiously waiting for it ever since. I also ordered a cap kit and replacement cd laser just incase.

fast forward to a few days ago, the duo arrived. I was ecstatic and plugged it in right away. the controller function was not working 100% and the volume was quiet and the adjustment knob didnt work. So I figured I might as well use the cap kit since it was suggested to do so anyways.

So I clean the board (not very well) with some alcohol and toothbrush and get to work replacing caps and resoldering somethings. Afterwords i go to plug it in. First nothing. Then i start getting a white screen, turning on and off quickly changes colors. From searching i have found this is a common error with a not so common solution. I went back to the board and noticed some of my caps had legs were not connected and I think a leg on one of the ics might have been bridged, it was a few days ago now...

Since then every time I go to fix something, something else ends up getting messed. I'm at my wits end and hoping anyone here can help out

Right now the issue is that the voltage regulator closest to ic 505  is outputting 0.4V, but the voltage regulator itself is working. I've tried two different regulators with the same result and tested them both to be working. Any idea on how this could happen?

[bozo55]

Hey there, sorry to hear you're having problems with your Duo.  While I'm no expert, I would like to try to help here 

- since it was working before you replaced the caps, I think that it is likely related to the caps specifically.  Did you double check the polarity on all the caps?  Did you replace all the caps?  Where'd you buy them from? And did you use flux on the contacts?  It can really help in ensuring a strong solder joint.

- can you please post some pictures, as it will help as well.

GL with the repair

[poponon]

I got the cap kit from console5. In hindsight i shouldve bought packs of each cap. I double checked the polarity and capacitance value of each cap more than once, I wish i had a capacitance meter to check them. The solder im using has a flux core , which can be messy sometimes. Is there any part of the board I should post pics of in particular?

This voltage regulator issue is just the latest issue I'm having. Other things along the way - fuse blew when i was moved the board the wrong way while checking voltage regulators, the original adapter blew, damaged trace and repairs, and embarrassingly I even managed to break a leg from an IC and had to repair that. It's a mess .. I'm shameful its gotten to this point

I've got a friends logic analyzer / oscilloscope / waveform generator also but after reading alot of repair logs I figure I need to track down this voltage regulator issue first. I've desoldered all the caps around the regulator .

some other questions - Is removing the SMD adhesive suggested?   Does anyone know of a place I can buy a capacitance meter locally in Canada?

[bozo55]

At this point you should either buy another one and have this as a parts system or commission one of the experienced people here to fix it for you (thesteve, Keith Courage, turbokon, BlueBMW, Game-Tech.US).

Once things start to go that bad it's hard to solve it without lots of experience.

[poponon]

I'd really like to try and fix this one if possible .. I wish i knew of a place that sold a cap meter nearby.

Edit -  On second thought after checking how much equipment i'd have to get I'm more open to someone else fixing it.  Do people normally just PM the guys or should I wait for someone to chime in.

I just wanna play some turbo this summer : ^(

[poponon]

Okay, if any tech would like to take on this job, let me know.

[poponon]

Lol I couldn't tell if you were being sarcastic or not with the whole ettiquette comment. I'll send some out.  thanks for the heads up

[burn_654]

I can definitely recommend thesteve, he got me up and running well after numerous issues. (distorted cd audio mainly) 

[pnauts]

If your regulator output 0.4V, you surely have a short circuit.
Check it off with ohmeter. If it's after your recap, I'll have a look on it.

[thesteve]

its fixed and headed home
it had several shorts

[pnauts]

Great !
another one saved from the trash. (A mod should update title with fixed)