My Duo .... Black screen buzzing

[MNKyDeth]

Ok, I am doing the Component mod. I previously replaced all the caps with ceramics and adjusted the pots for the cd-rom. Everything worked fine at this point with the default 5pin Din on the side of the Duo composite.

After wiring up the component board and being very meticulous about it, it was time to test it.
I hooked it up to the tv via the custom 8pin mini din to composite cable I made.

All I got was a black screen and buzzing. I was nervous so I quickly shut the Duo off. I then removed that cable and put in the original A/V cable (composite) and I got the exact same result. So...

I am double checking my connections to make sure I didn't miss anything and that everything is connected and not shorted especially on the RGB legs on the 6260 chip.

During my component mod the other things I did this time around while my Duo was open was to completely spray down and remove any corrosion I may have missed the last time with some Quick Dry electronic cleaner. I used this the time before when I replaced the caps so I assume that didn't cause the issue but wanted to mention that I sprayed down the board once again.

Beyond checking my connections I made for the component board V2 and RGB amp the only thing I can think of to check is to start going from cap to cap to make sure I am getting voltage at each location.

I am posting to see if anyone has an idea of where to look first so I don't waste a lot of time checking every little thing if I don't need too. I just hope I didn't damage any chips on my board by turning it on and getting the result I had.

Thanks for any info or tips

[MNKyDeth]

Ok, bit of an update...

I went through and did a continuity check on all my connections to make sure I didn't bridge anything. Like the pins next to the RGB lumin etc. All seems good no sound when measuring the legs next to ones I was supposed to use and I had sound on the pins I thought I soldered to.

I went through and rechecked the caps and all looks good.

I am going to disconnect the mod and see if the system works. I am starting to freak out I damaged something I just don't see anything wrong.

Btw, on a Duo is there a better place to solder too than the legs of the 6260 chip?

[MNKyDeth]

Ok, I made sure the legs on the 6260 chip that I had the wires soldered to were making contact with the board after removing the wires. It looks like I never touched them to begin with.

I removed the mod chips and put the system back together and gave it another test. I am getting the same issue now with my system exactly as it was the last time I used it about two days ago. Two days ago it worked and now it doesn't.

I checked each cap with my multimeter for continuity and all looked good but I guess I need to go back and double check. Also... How do I tell or how can I see if I have a bad trace?

I honestly don't see any corrosion beyond what I had before when I replaced the caps. So I feel a trace went bad or I did something to my system while doing the mod but nothing is looking obvious to me at the moment.

[MNKyDeth]

I went through and touched up each cap to make sure they were making good contact. I still have the same result so I assume I have a bad trace somewhere.

So I guess now begins the tedious task of using my multimeter and checking for continuity between different point on the board. Gah....

This will most likely be my last post for a bit while I am searching my board for a bad trace. If anyone has any ideas they are welcome.

[MNKyDeth]

Ok, I am really at a loss now.

What I did was put one test lead on one edge of a cap then measured some where down the trace to see if there was continuity. Every single cap tested good to some where else on the board.

I then measured the legs that I had soldered too, to somewhere else on the board following the traces and they were all good as well.

So.... I went to my TurboDuo wart. The specs read 10v 1000mA
I had 0.665v DC and my mA rating was all over the place so I am wondering if this is my TurboDuo power plug now.

I can't seem to find another plug that fits the Duo connector. I do have a Sega Genesis wart and some other random wall warts. Just none of them have the proper plug to fit so.... Guess I am ordering a new power plug.

Any recommendations on one that will work with the US Duo?

I think it's pretty official... My Duo wall wart is dead. No matter where I plug it in it reads the same 0.688v DC. I tried several other wall warts and they read correctly on my multimeter. So I know my meter is reading correctly and for whatever reason it decided to give up the ghost while I was doing my component and RGB mod. I am still a little worried for the system but I know by checking everything caps, connections, traces etc I feel I did a proper job on my system and it was just the wall wart messing with me.

console5.com has an adapter for sega wall warts and a RadioShack wall wart. I think I am gonna buy the radio shack one. Not sure if there are other better ones out there for me but I guess I gotta start someplace.

[thesteve]

the supply has a fuse in it

[MNKyDeth]

Omg lol ... I already placed the order on console5.com well... I will have an extra then. Tearing apart my wall wart now.

Ok, now that I have the bad fuse removed I just need to wait for the local hardware store to open to buy a replacement. Hopefully they have one.

What would cause the fuse to blow in the wall wart? Just from plugging and unplugging it? Just old? Anything to do with the mod?

[thesteve]

if you had it plugged in with the board loose it could have shorted across the plate

[MNKyDeth]

Ok, well I drove all over town looking for a fuse and the closest one I could find locally was Bussman Fuses BP/GDC-5A

I will use this just to test the system but not run long term. I have ordered

Bussmann GMA-5A 5 Amp Glass Fast Acting Cartridge Fuse, 125V UL Listed, 5-Pack
http://www.amazon.com/gp/product/B000HOSZVA?psc=1&redirect=true&ref_=od_aui_detailpages00

As that seems to be a better fit not being time delay etc.

Now... I replaced the fuse in the power supply and I read it with my volt meter and all seems good. I hook my Duo up to my TV via it's composite port and the Component port to my tv as I wanted to compare the two side by side. This would also help me set the color settings as I could compare them.

When I turned on the sytem the video came right up this time and I was extremely relieved I didn't kill my system. lol
When I switched to the composite channel I received an "Invalid Format" error on my screen.

So.. I either made my cable wrong, which I don't think I did. Or I need to adjust the pots on the V2 component board so my tv sees it properly. Or I don't know.

But for reference my TV is...

LG Plasma TV - Model = 42PJ3350-UB

I am going to play around with the pots some see if I can get it to do anything.

[MNKyDeth]

Ok, well I double checked my wiring, it seems ok for what I did but I still may have done something wrong with it.

If I turn pot R3 all the way clockwise I get a "no signal" on my TV. Once I start turning it counterclockwise the message on the screen turns into "Invalid Format".

I am looking at some pics of composite type A/V cables. The wire mesh on the outer edge I understand is ground I did not hook the mesh up to anything and just ran the signal Y, Pr, Pb through the center wire.

My audio cables have two wires built in them and I did hook up a ground on those so I believe I just need to wire the ground to the other three wires on the mesh.

I have another post in this mod forum with pics of my cable hopefully that can help people see what I have done for a custom cable.



Edit:

Well, looks like grounding the shielding on the video parts of the cable is not going to fix the issue. I get the same response from he TV. Invalid Format or No Signal. If I turn it exactly in the middle of the two errors on screen I stop having an error message appear but the screen is still black and no matter how I adjust the R1 or R2 they have no effect.

I played the first two levels of Air Zonk on the composite cable and switched over to the component connection every now and then to see if there was any video displayed with a game but that was also a no go.

Maybe my TV doesn't like the component connection. Well, I been at this all night so time to take a break and get some sleep. Tomorrow morning after work I will have another go at it.

[ProfessorProfessorson]

The component board does not work on every HDTV, plasma, LCD, or otherwise. You need to test your TV to make sure it can display 240P via component. As for the power supply issue, if it makes you feel more secure about it, you can get hold of a Sega Genesis 1 power supply that does 1.2A on the output and just swap the cables with the one from the Duo psu. As you add more components into the Duo, the power draw is going to increase slightly.

As for the laser adjustment, make sure you don't hear any whine noise off the laser or get any skipping during playback. Play through  a couple of long music cds (original pressings), and find a few games, also originals, not cd-r, to try out that are good for testing to make sure the laser will read the disc across the board. Valis 4 is a good test, because it does a lot of data/audio tracks throughout the disc, instead of just clumping the data near the center like most disc. This way you can make sure your laser is reading the disc correctly at all of the spin rates.

Also, if your laser has to do a lot of sliding back to center when trying to read data, and keeps making that light klonking noise as it hits its dead stop switch, that is one tale tale sign that its not calibrated right.

[thesteve]

now the supply has a 5A fuse and the duo has a 3A fuse in line with it, so to blow the supply fuse instead of the duo fuse pretty much says you shorted it before the switch
invalid format generally means incompatible tv

[MNKyDeth]

I have moved the power plug over to a power strip instead of straight into the wall. I am also Hong a different wall outlet and I have the building maintenance guys scheduled to come check out the outlet I had plugged the power plug into.

Well, I thought the tv would accept the component because it has component connections. But I also have the composite plugged into the tv and that works so I thought it would support the 240p.
The weird thing to me is that the composite fills the screen and it doesn't look stretched, just a little blurry but playable.

Oh well, just gives me more of a reason to get a framemeister now.

[thesteve]

thats why we say to try your TV with composite hooked to the luma (Y) plug before you ever order the board
if you get a B/W pic you should be good

[MNKyDeth]

The end result is still good. As who can say they have a component chip and an RGB amp in the same console with the original composite still intact.

And I am not worried about it either. It gives me more options on my Duo for different situations. Besides I have learned a lot and still learning.