Game Gear McWill Screen Help?

[Makara]

Hello all, I am fairly new around here.

 

Today I decided to upgrade one of my GGs to a McWill screen. I bought it from Retrosix. Afte fitting, I get a blank screen, and no sound. I've check the voltage and the board is showing 4.82v, and I've been over the connections and all looks ok, I've checked continuity and for shorts on the LCD wires and they were all good. I didn't receive any instructions with it so I used those found on other sites, and since Retrosix included capacitors I followed the earlier version guide and replaced them. I didn't receive a VGA port with it.

 

Does anyone have any idea what the problem might be? Also, does anyone know how to tell whether it's a genuine McWill kit and not a chinese knock-off?

[+-^CrossBow^-]

Well...the current McWill kits come with a red PCB. As for the blank screen, I've only seen that happen when I didn't have a good ground attached to the McWill LCD board, or I wired up the contrast wheel for VGA output, don't actually have VGA and have the contrast wheel in the full down position that would normally be for switching on VGA mode. But you aren't using VGA. I will look at your pics in a bit to see if I can find anything obvious.

 

But here is a new McWill kit that I just installed the other day into a single ASIC like yours. I purchased my kit directly from Console5.

 

 

[+-^CrossBow^-]

Wait...WHY do you have a wire off the CSync connection off the board? That is only required for the VGA output. My guess is the wheel is in the down position even though you don't have the backlight swtich off wire in place.

 

Here is another one I did earlier this week on a Twin asis model that doesn't have VGA out installed. No Sync wire needed...

 

Also like you I connected all the wiring in the exact spots shown on the guides, but connected my +5 on the component side of the board to keep that wire on the same side as the others on my second one shown above. Also, you can grab the ground from LOTs of places on the GG mainboard and I just use of the anchor pads for the LCD for that since it is right there and also part of the main ground plain.

 

 

 

[Makara]

It looks like I soldered BUT3 to the wrong side of C36 - will switch that over tomorrow. I wonder if that's the cause?

 

I'm fairly sure it's a knock-off then, I was suspicious when I saw it and the price was too good to be true.

[+-^CrossBow^-]

Current McWill kits cost $90 now. Or at least that is the new pricing used at Console5. McWill did lower the price on his kits to help compete against the clones and other competitor kits.

 

But again...why do you have the csync wired up if you aren't using the VGA?

 

While I've not looked at the schems..My guess is the BUT wires are for the button controls to change the resolutions and scanline modes. So even if you didn' thave those attahced I would guess it still would come up in its default mode.

 

[Makara]

2 minutes ago, -^CrossBow^- said:

Wait...WHY do you have a wire off the CSync connection off the board? That is only required for the VGA output. My guess is the wheel is in the down position even though you don't have the backlight swtich off wire in place.

 

Here is another one I did earlier this week on a Twin asis model that doesn't have VGA out installed. No Sync wire needed...

 

Also like you I connected all the wiring in the exact spots shown on the guides, but connected my +5 on the component side of the board to keep that wire on the same side as the others on my second one shown above. Also, you can grab the ground from LOTs of places on the GG mainboard and I just use of the anchor pads for the LCD for that since it is right there and also part of the main ground plain.

 

 

 

Oh should that not be there? The guide said leave the backlight wire but didn't mention CSync - I will disconnect it. I did play around with the wheel and it made no difference.

 

I like your wiring, that's neat, maybe I will rearrange it!

[+-^CrossBow^-]

Look at my previous reply. I edited it and added in the part about the BUT connections. To sum up, I'm pretty sure those are just for wiring in the controls for changing the screen and you could leave them off and it would work in default screen mode without the ability to change it if you left them off.

 

[+-^CrossBow^-]

Another gotcha I mentioned to Console5...you removed R30 even though that isn't specifically listed in the current 2.2 revision docs. The pic with it highlighted as if to remove it, is still present but you don't remove R30! Again McWill was reusing his old pics for this guide. So follow it word for word and don't rely on the pics. I almost got hung up on that one too. So hopefully you still have that little resistor to reattach it?

 

Here is the part about the Csync and yes it is written a little confusing..

 

"!!! If you DON'T want to install the VGA
connector, you can leave the BACKLIGHT wire!
Otherwise solder 1 wire from BACKLIGHT of
the GG mod to PIN2 of the thumbwheel and 1 wire
from CSync of the GG mod to T2 of the GG PCB."

 

So I read this to mean that if you aren't using the VGA then you can leave the backlight wire off... the Otherwise, tells me it goes along with the VGA. So you can skip the backlight wire and the Csync and go straight to the BUT wire connections from there.

 

[Makara]

So confusing - I don't think I have the latest version of the board do I? Mine is green (and probably a knock off). Since Retrosix sent me 2 capacitors and a resistor I followed the guide that incorporated those, which also said replace R24 with R30.

 

I do still have all the removed parts so I could put it back on. It's something to try I guess. I'm hoping one of these things fixes it, otherwise I may just scrap this and buy a genuine kit from a reputable store (which is what I thought I was doing).

[joeatari1]

My GGs are famous!?

 

 

 

[+-^CrossBow^-]

16 minutes ago, joeatari1 said:

My GGs are famous!?

 

 

 

Hey you haven't seen these pics yet!!! You're peeking! BTW..check your email!

 

[+-^CrossBow^-]

2 hours ago, Makara said:

So confusing - I don't think I have the latest version of the board do I? Mine is green (and probably a knock off). Since Retrosix sent me 2 capacitors and a resistor I followed the guide that incorporated those, which also said replace R24 with R30.

 

I do still have all the removed parts so I could put it back on. It's something to try I guess. I'm hoping one of these things fixes it, otherwise I may just scrap this and buy a genuine kit from a reputable store (which is what I thought I was doing).

That does sound like the older version guide stuff so let me look that over and see if R30 does get removed for that. But no...the latest McWill GG LCDs have the red colored PCB and have for I think about a year now or at least since the V2 boards came out. These latest versions are a tad easier to install with less stuff getting removed and installed in other places. On the twin asic you just remove stuff and wire up. The single ASIC like you have, only requires some 0hm bridge resistors to be installed in place of the originals in one spot. You still have to remove like a dozen components but there isn't any need to reuse anything as the older instructions required.

 

[Makara]

9 hours ago, -^CrossBow^- said:

That does sound like the older version guide stuff so let me look that over and see if R30 does get removed for that. But no...the latest McWill GG LCDs have the red colored PCB and have for I think about a year now or at least since the V2 boards came out. These latest versions are a tad easier to install with less stuff getting removed and installed in other places. On the twin asic you just remove stuff and wire up. The single ASIC like you have, only requires some 0hm bridge resistors to be installed in place of the originals in one spot. You still have to remove like a dozen components but there isn't any need to reuse anything as the older instructions required.

 

Update: it's working!

I could kick myself - the problem was the R25 resistor, although it appeared to be soldered down, when I checked it again it was showing as open - resoldered it and boom it fired into life. Very happy! I also switched over the C36 wire and removed the Csync wire.

Thanks for your help!

Edited May 17, 2020 by Makara
pics

[+-^CrossBow^-]

Awesome! Glad you got it up and going! I did look over the older procedures and had forgotten that it was slightly more of a pain as compared to the current procedures with the current McWill kits.

 

[scrappysphinx]

I also purchased a screen from retrosix last week and it also came as a green pcb. I also used their ceramic cap kit to recap the game gear and after fitting the screen i was presented with a high pitched whine/squeal. I contacted retrosix who told me the 820uF cap they provide in the kit for the power board is known to do this and i should put the original 820uF back and see if the problem goes away. Sure enough it did. I also posted in a retro console modders facebook group (i believe crossbow above was one of the people to reply on my post) where a number of people said my screen might be a clone board because its on a green pcb and has McWill's name on a sticker rather than part of the silk screen. I asked retrosix again and he sent me a message back saying he buys direct and even helps with the pcb revision designs. I was hoping to send McWill a pm on here to query if it was genuine or not but it says he can't accept messages. 

[Makara]

It's interesting that he didn't say why he was selling the old version of the board. I'm fairly sure mine was a clone board.

• it was a lot cheaper than any others I could find by about £20 (but not as cheap as buying from Aliexpress...)
• the paper sticker just looks wrong
• the newer red version has apparently been around for a year now
• it didn't come with a VGA connector or any printed instructions

Would be good if McWill could advise, but I guess he is a busy man.

[scrappysphinx]

Mine didn't come with instructions or the vga connector either, just the screen and a couple of smd parts. 

 

I have sent an email to McWill on the order-lynx-lcd@online.de address and hopefully he'll answer but we shall have to see.

[scrappysphinx]

Just to update this, as i mentioned above i emailed McWill on his order email address and received the attached reply this afternoon. 

It seems the screens retrosix supplied are indeed genuine. 

 

[+-^CrossBow^-]

Interesting, I wonder why the VGA connectors and instructions aren't being provided? I can't image that the VGA connector saves that much in costs per kit does it but maybe it does?

 

I also wonder why the kits McWill is providing to Retrosix directly are the older green PCBs and not the current red ones? It does make it more difficult to know for sure if you are getting a true McWill kit. I'm glad to know that the kits Retrosix is selling are indeed genuine but it doesn't ease the confusion much and now that the sticker has been shown, it won't be long before the Ali specials start to include stickers on them as well...ehh?

 

[Makara]

Well it's reassuring to know these are genuine from Marco himself, though if I ever sold my GG I think I would have a hard time convincing anyone that it was a genuine Mcwill screen.

[+-^CrossBow^-]

I've not seen what the clones look like, but I've been told their LCD panels aren't as good a quality. They do the job and still look really good but apparently not as good as the LCD that McWill is using. But again, I've not seen one first hand to compare.

 

[xelement5x]

Just installed a genuine McWill myself (Red board V3.1, a friend got it for me through Console5 since he was already ordering stuff) and wanted to mention another possible issue for the blank screen.  When I installed the wires for the backlight adjustment I had apparently just barely bridged the backlight jumper on the board (it is the two half circle pads).  The solder spot between them was just a spec, but that's all it took.  I checked with the multimeter and then removed it and everything was working fine after that.  

 

Also, given the location of those backlight pads you almost need to do the full install first without tacking the screen down, then adjust the screen location at the very end.  I'm pretty dexterous with a soldering iron but getting to those backlight pads under the cart slot would not be fun.