Duo-R not turning on

Siskan · 10/19/2015, 07:10 PM

Hello there!
One day, my Duo-R woulsn't turn on anymore. I've tried the original adapter and a step-down converter (I'm in Europe, so I was using a third party cable), but that's the only check I could perform due to lack of knowledge about these kinds of things.

I was going to send it to a company here and have them fix it and do an RGB mod while I was at it, but as they just nearly doubled the price for the latter, I no longer think it's worth it. So I'm kind of wondering if it's a simple fix I could do on my own (or at least find out if it's repairable before I waste money on shipping).

So basically my question is where I should start with troubleshooting my console?
I suppose there's some kind of fuse in there which could be the problem, but I don't know how to tell.

I might just as well ask if there's any up to date step-by-step video for the RGB mod as well? It's probably too complicated though as I have next to no experience (I learned to solder and make a toy car roll forward back in school but that's it). But hopefully the fix should be simple enough.

schweaty · 10/19/2015, 07:23 PM

Start simply: check the voltage on the ac adapter with a multi-meter.

If it is showing the correct voltage, then open up the duo and check the fuse for continuity with a multimeter.

If the fuse is good, check the input and output voltages of the 7805.

Siskan · 10/19/2015, 07:35 PM

Quote from: schweaty on 10/19/2015, 07:23 PMStart simply: check the voltage on the ac adapter with a multi-meter.

Hm... I'll see if there's one in the shared workshop of this apartment building tomorrow then. I don't know if there is one and I don't own any myself.

Is the 7805 a regulator? I don't really know anything like I mentioned. I do very much appreciate your help though!

SignOfZeta · 10/19/2015, 08:45 PM

Isn't the Duo R the NEC system with no fuse? I thought it was. I can't remember.

Keith Courage · 10/20/2015, 12:38 AM

I bet you that either the power jack or av jack has cracked connections. duo-r and RX systems are notorious for this. Just re-solder the pins for them and all should be good.

If neither of those are the problem then definitely look into the 7805 voltage regulators like schweaty said.

While you are in there you might as well re-solder the pins for the controller port as well. This is another area that typically gets cracked connections.

jugu · 11/19/2015, 01:48 PM

Not to hijack this thread. But I just picked up a Duo which is not turning on. The AC adaptor seems to be working, so I'll have to open this guy up.

I'll take the suggestions made in this thread in begin with the fuse and go from there.

Wish me luck!

GohanX · 11/19/2015, 02:36 PM

Yeah, check to see if the ac adapter has power, and then check the fuse. Then we go from there.

I found out the ac adapter has a fuse too a couple weeks back!

jugu · 11/19/2015, 03:29 PM

Turns out I had the bit to open the console up.

The fuse seems to be fine, passes the continuity test. I'm having hard time touching the pins for the 7805 as the leads to my meter are obscured by the large capacitors.

Here are some pictures. The power connector appears quite rusty. I'll check the pins on it next.

https://imgur.com/QZZ5ON6
https://imgur.com/FqunifC
https://imgur.com/a7w59jI

Any thing else looks suspect to your expert eyes? Oh and Siskan, I hope you don't mind me using your thread. I'm new to the world of the PC Engine and it looks like we both could use some help. I can start my own thread if necessary.

jugu

Keith Courage · 11/19/2015, 09:14 PM

Did you check the AV and power jack yet? Those are known to get cracked connections and typically need to be re-soldered.

Siskan · 12/29/2015, 10:24 AM

Quote from: Keith Courage on 11/19/2015, 09:14 PMDid you check the AV and power jack yet? Those are known to get cracked connections and typically need to be re-soldered.

I neither had time or a multimeter and the correct screwdriver, but I do now.

The adapter ouputs 9.24 volts. I don't think that's too much?

I also pick the same value up on the other side of the power jack so I assume it's working correctly?

The fuse seems to be fine. Constant beep during the continuity test and it also looks fine.

Where are the 5805s located located? I'm not entirely sure what they look like, so those were the only ones I couldn't test.

Vimtoman · 12/29/2015, 11:04 AM

Check the power switch using continuity on the meter.
Usually it has a speaker symbol on the meter.
do this when no power is applied.
of thats OK
Then power ip and .
Check the 5V supply.
I think the Duo-R has two 7805 regulators.
Looking directly at them the middle pin is Gnd and the right pin is 5V out.
Use the shield over the Hucard as a Gnd using the black probe on your meter.
Then place your red probe onto the right leg of the regulator.
test both.

Siskan · 12/29/2015, 11:24 AM

Quote from: Vimtoman on 12/29/2015, 11:04 AMCheck the power switch using continuity on the meter.

Thanks for the quick reply! Bear in mind that I barely have any experience with electronics though.

I don't know where to make contact around the power switch. There is a big metal block in front of it, I don't know if that's what I'm looking for, but if I put both of them on it, I do get the constant beep. Everyhting else seems to be guarded by plastics.

5V supply? Do you mean the 9V power supply?

Still can't locate the actual regulators. Could you perhaps point them out on this (not my photo)?

Vimtoman · 12/29/2015, 02:19 PM

Top left hand corner there are two aluminium heat sinks with the regulators attached.

Siskan · 12/29/2015, 02:54 PM

Quote from: Vimtoman on 12/29/2015, 02:19 PMTop left hand corner there are two aluminium heat sinks with the regulators attached.

Thanks! The result was 5.0 for both

Keith Courage · 12/29/2015, 03:13 PM

Quote from: Keith Courage on 11/19/2015, 09:14 PMDid you check the AV and power jack yet? Those are known to get cracked connections and typically need to be re-soldered.

Siskan · 12/29/2015, 03:36 PM

Quote from: Keith Courage on 12/29/2015, 03:13 PM
Quote from: Keith Courage on 11/19/2015, 09:14 PMDid you check the AV and power jack yet? Those are known to get cracked connections and typically need to be re-soldered.

I have checked the power jack as described above. I could check the AV jack too, but as the console doesn't light up and the CD doesn't spin, I assume it's more than an issue with the picture.

Vimtoman · 12/29/2015, 04:36 PM

Where in Europe are you based?

Siskan · 12/29/2015, 04:38 PM

Quote from: Vimtoman on 12/29/2015, 04:36 PMWhere in Europe are you based?

Sweden.

Vimtoman · 12/29/2015, 06:42 PM

Ah Ok If you were closer I could help you out.

Siskan · 12/29/2015, 08:58 PM

Quote from: Vimtoman on 12/29/2015, 06:42 PMAh Ok If you were closer I could help you out.

I appreciate that as well as the help you have offered in the thread until now. Thanks.

So does anyone else still have any clue?

thesteve · 12/30/2015, 10:02 AM

Quote from: Siskan on 12/29/2015, 03:36 PM
Quote from: Keith Courage on 12/29/2015, 03:13 PM
Quote from: Keith Courage on 11/19/2015, 09:14 PMDid you check the AV and power jack yet? Those are known to get cracked connections and typically need to be re-soldered.
I have checked the power jack as described above. I could check the AV jack too, but as the console doesn't light up and the CD doesn't spin, I assume it's more than an issue with the picture.

as the system doesnt light up or spin CD before closing the lid and pressing run it could still be a video issue

Siskan · 12/30/2015, 10:08 AM

I'm pretty sure I pressed Run back when I first discovered this just because I thought it could be video related. There was no light, spin or sound anyway.

How would I check the AV jack anyway?

thesteve · 12/30/2015, 10:34 AM

well in most cases try wiggling it
also try a card and see if you get sound
only way to know for sure if its turning on is get a meter and check the 5V off the regulators

Siskan · 12/30/2015, 10:35 AM

I have tried a HuCard as well. And the regulators are working as they should.

thesteve · 12/30/2015, 10:41 AM

well if the regulators are working then it is on, and you can move up to "why no pic" why no sound"

Siskan · 12/30/2015, 10:45 AM

Well if you say so! I'm the clueless one. Is the light dependent on the picture traveling properly though? Sounds odd. What could I check next?

thesteve · 12/30/2015, 10:54 AM

the light is dependent on the CD system properly starting
so when turning on what does the screen do?
does it flicker, flash, blank screen ect
if it does nothing check your AV cable with a meter, its direct wired

Vimtoman · 01/01/2016, 04:58 AM

Ive been through this lot with Siskan via PM.
The cable is the last test i had left him with.