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NEC PC-Engine/SuperGrafx => PC Engine/SuperGrafx Discussion => Topic started by: Lord Thag on October 18, 2008, 08:00:46 PM

Title: My Duo-R is dead
Post by: Lord Thag on October 18, 2008, 08:00:46 PM
I need a hand here guys. I bought a Duo R not three months ago, which worked perfectly.

Until now  ](*,)

When I went to play it today, it found that, upon flipping the power switch, it did precicely nothing.
It's plugged in, I've tried two different power adaptors. I've tried it with Hucards and CDs and both, and neither.

Nothing. No LED lit, no flicker on the TV, nothing. Jiggling cables does nothing too. I'm really frustrated here, because it looks like I spent $200 on a paperweight. I can't afford another one.

Please tell me there is something I can do here... :cry:
Title: Re: My Duo-R is dead
Post by: termis on October 18, 2008, 09:09:15 PM
Sounds like a blown fuse somewhere.  Should be an easier fix than most problems.  Replace that one little sucker and you should be good to go.

One of the guys here who open the systems up regularly probably could tell you exactly where the fuses are located on Duo-Rs.
Title: Re: My Duo-R is dead
Post by: Duo_R on October 19, 2008, 12:00:38 AM
Thag checked the fuse, it was ok. Thag get your multi-meter out and start checking th 7805. Zeon walked me through last night, and I brought another dead system back to life. Mine had not only a bad fuse, but a bad 7805. If your fuse was still good, maybe your 7805 went bad as well.
Title: Re: My Duo-R is dead
Post by: SignOfZeta on October 19, 2008, 04:57:45 AM
Um...I seem to remember the Duo R not having a fuse. Did I just miss it or something? What does it look like? It isn't the glass cartridge type like in older NEC systems, I know that.
Title: Re: My Duo-R is dead
Post by: Duo_R on October 19, 2008, 06:27:19 AM
U know I heard someone say that before, and I was planning on installing an inline fuse. However, when I took a look under the hood there was the same fuse found on my US Duo.
Title: Re: My Duo-R is dead
Post by: SignOfZeta on October 19, 2008, 04:50:43 PM
U know I heard someone say that before, and I was planning on installing an inline fuse. However, when I took a look under the hood there was the same fuse found on my US Duo.


Hmmm, I was under the impression that there was only one version PCB for the Duo R, and I do not have a glass fuse.

Can you circle where about it is on this picture? I stole this from Assembler. I don't see on on his either.

(http://img64.imageshack.us/img64/117/pceduor10ix.jpg)

I actually bought my Duo from a guy that couldn't get his to fire up. I assumed it would be a fuse so the first thing I did (before even turning it on) was open it and check the fuse. It doesn't have one though. So I cleaned all the case grounds and put it back together and turned it on and it worked. Soon after I replaced the power supply with the Radio Shack one, and it hasn't f*cked up on me once since then.
Title: Re: My Duo-R is dead
Post by: Duo_R on October 19, 2008, 06:04:06 PM
u know I was just working on a standard PC Engine the same day i worked on the Duo-R, so I must have got them confused. I think you are right, so back to my plan of installing a fuse.
Title: Re: My Duo-R is dead
Post by: Zeon on October 19, 2008, 07:07:17 PM
U know I heard someone say that before, and I was planning on installing an inline fuse. However, when I took a look under the hood there was the same fuse found on my US Duo.


Hmmm, I was under the impression that there was only one version PCB for the Duo R, and I do not have a glass fuse.

Can you circle where about it is on this picture? I stole this from Assembler. I don't see on on his either.

(http://img64.imageshack.us/img64/117/pceduor10ix.jpg)

I actually bought my Duo from a guy that couldn't get his to fire up. I assumed it would be a fuse so the first thing I did (before even turning it on) was open it and check the fuse. It doesn't have one though. So I cleaned all the case grounds and put it back together and turned it on and it worked. Soon after I replaced the power supply with the Radio Shack one, and it hasn't f*cked up on me once since then.


I must have a fuse somewhere, it's just plain stupid design not to have one. I haven't opened up my duo-r yet, but it is likely it uses a pico fuse like the sega cd and snes. they look something like this:

(http://i78.photobucket.com/albums/j83/mini_zeon/251fUSE.jpg)

There may be a fried diode as well that needs replacing.

Also replace the two power regulators i circled in the picture below. Trust me if the system is not powering after replacing the fuse (once you find it, there must be some sort of fuse). Then the next likely suspect is the power regs. They regulate the voltage down from the rating on the ac adapter down to a nicer voltage that the chips inside of the system can use. If the system was ever overjuiced they would have eaten up all of the excess voltage(or if polarity was swapped) and would have fried thus cutting off voltage to the rest of the board. No need to test em really, just replace em, voltage regs are very cheap (looking at 30 - 40 cents max a pop, or 6 times that amount if ratshack actually stocks the needed item and is your only viable option). Since the system doesn't even power on what do you have to lose?

(http://i78.photobucket.com/albums/j83/mini_zeon/pceduor10ix.jpg)
Title: Re: My Duo-R is dead
Post by: nodtveidt on October 20, 2008, 12:50:26 AM
ratshack here usually has 'em stocked by the dozens. And f*ck Stabby McStabbins. :P
Title: Re: My Duo-R is dead
Post by: Lord Thag on October 20, 2008, 05:02:36 AM
Thanks for the advice everyone. My motherboard has a fuse (left side center), but that's fine. I'll replace the voltage regulators next. *crosses fingers*
Title: Re: My Duo-R is dead
Post by: Lord Thag on October 27, 2008, 05:35:32 AM
Just wanted to say thanks again for the input everyone. The Duo has been resurrected! It was the two voltage regulators (thanks Zeon!). She purrs like a kitten now :)
Title: Re: My Duo-R is dead
Post by: guyjin on October 27, 2008, 09:22:39 AM
Yay! another PCEngine saved from the scrapheap!  :dance:
Title: Re: My Duo-R is dead
Post by: ceti alpha on October 27, 2008, 09:51:09 AM
*Does the happy dance*  :dance: :dance: :dance: :dance: :clap: :clap: :clap: :clap: :clap:
Title: Re: My Duo-R is dead
Post by: Ninja Spirit on October 31, 2008, 06:13:26 AM
(http://b.pcb3.fubar.com/55/16/736155/2639633637.gif)
LOL Victory dance