The Elusive VA7

[evildragon]

Ok, so I found my VA7 Genesis and snapped a picture of it. Notice the chips are like that of the Genesis II except the Z80.

http://img.photobucket.com/albums/v395/Evilweredragon/IMGP3077.jpg

[Baloo]

What the hell? Is that a Genesis motherboard on a Sega-CD?

[streetsofrage]

the va 7 sucks

[evildragon]

Yes, the Genesis VA7 motherboard on the Sega CD. The cartridge slot doesn't work despite it having good contact.

And the VA7 does suck, after listening to it's audio. Atleast stock, the audio sucks.

TmEE: If you want me to get a high resolution pic of the mainboard, I can sure do that. It'll be massively large though, like 3800 pixels wide.

[streetsofrage]

are u going to mod it ?

[evildragon]

It was going to be my Neptune project, but the cart slot failed for some reason on me and I never got to actually finishing it like I wanted to. That's why my Neptune project went on hault.

[tomaitheous]

TmEE told me that model has the best sound of the model 1's after his CAMM upgrade. I've never thought much of it (I have one).

[evildragon]

TmEE told me that model has the best sound of the model 1's after his CAMM upgrade. I've never thought much of it (I have one).

After his mod, I can see that it being the same chip as the Genny II. But without the mod it's a highly muddy sounding console.

[Chilly Willy]

Connectors like that often develop cold solder joints after a number of years. Especially if they are subject to frequent use. I suppose you tried resoldering the connections? If you accidentally bridged two connections, that could cause a problem. I'd run a VOM down each side looking for two pins shorted together that shouldn't be. If you did some heavy soldering on the connector, I've seen edge leaves inside the connector move out of place as they melt the connector a little from the soldering. If a leaf doesn't make firm connection, you could have trouble. Those would be the first things I checked, in that order. If you've already done all three, sorry about that. Just tossing out some ideas. :)

[TmEE]

VA7 is MD2 in MD1 shell, one to one, except for analog parts and few resistors here and there being different....

315-5487 is functionally identical to 315-5660 found in most MD2s, the first is seen in MD2s aswell, though not as often. these ASICs are pin and function compatible.
315-5700 is also pin and functionally compatible to these, and its used only in Nomad (possibly lower power version) so you can nicely hook it up to MegaCD and 32X or PBC if you make correct connections... I've done the 32X and PBC stuff, I'll be tackling MCD soon :)

I have quite a few good pics of the VA7, but a nice pic of the bottom of the board would be nice :)

[evildragon]

Here ya go.

http://img.photobucket.com/albums/v395/Evilweredragon/va7.jpg

I couldn't get uniform light as I'm not at my studio to perform a perfect shot. And thus had only one stage light for this (top).

But I'm sure it'll do.

EDIT: The solder joints are empty on the cart connector cause I'm now resoldering them. ;)

[TmEE]

thanks for the pic, no problem with the lighting, everything needed is visible.

Did you add the cap on the cartslot or was it always there ? same goes for that resistor

[evildragon]

always there.

[Christuserloeser]

The possibility of haveing a CCAM'd model 1 is kinda neat... - How could I tell that I got a VA7 in front of me ? What are the things that would make it obvious ?

[kool kitty89]

No DE-9 EXT port next to the RF+AV ports, but I think this is true for the VA-6 as well. There may be a difference in the serial # though, and maybe the RF sheilding seen at the bottom. Otherwide you'd have to open it up, then it's easy, no YM2612, QPF 68000, and VA-7 printed on the board.

[Ace]

The easy way is to look at the placement of the hookups. If they're near the side of the console, it's a VA6, if they're closer to the center, it's a VA7. Christuserloeser, could you take a picture of the back of your Genesis where the hookups are?

[evildragon]

The possibility of haveing a CCAM'd model 1 is kinda neat... - How could I tell that I got a VA7 in front of me ? What are the things that would make it obvious ?
black expansion port contacts vs silver.

[Mordan]

this post is l33t :)
I don't understand a thing

[edojapan76]

black expansion port contacts vs silver.

on my mega drive they are blue, not silver.

[evildragon]

on my mega drive they are blue, not silver.

They are never blue. Its black or silver. This is the sega cd connector on the side

[Christuserloeser]

Ace: The only consoles I have with me right now are two Japanese Mega Drives and a HDG Genesis. - I just wanted to know in case I ever come across a non-HDGAS PAL Mega Drive. I know that two of my friends have units without that logo (and comparably thin sound).

Thanks for your advice, everyone. :)

[Ace]

You can tell by the sound. If you hear what sounds like hissing in a game's music(Thunder Force II MD is perfect for that), the system has a VA7 motherboard. I think the VA7 board is actually more common in North America than anywhere else. Seriously, the vast majority of Genesis Model 1s I see are VA7s.

And as Evildragon said, if the Sega CD contacts are black instead of silver/copper, that's a VA7 motherboard you've got.

Not sure if the hookups being shifted towards the center actually applies to European MegaDrives if they contain VA7 motherboards, but I do know for a fact that all Japanese MegaDrives have their hookups shifted towards the center no matter the motherboard.