Two or three layer mobos?

I would be interested to know which boards have triple layers of track (one sandwiched in the centre)rather than the standard double sided print. Its easy to tell at a glance, the jamma edge connect board material is opaque on a two layer, on a three layer you can see the centre copper track in the board. See piccys.

<a href="http://www.boomspeed.com/ttooddddyy/doublesided.JPG" target="_blank">http://www.boomspeed.com/ttooddddyy/doublesided.JPG</a>

<a href="http://www.boomspeed.com/ttooddddyy/threelayer.JPG" target="_blank">http://www.boomspeed.com/ttooddddyy/threelayer.JPG</a>

So far have established
MV1 3
MV1F 2
MV4 older ver 2
MV4 newer ver 3
MV6 2

Thanks MKL for the info on the 4 slots.
Whould appreciate info on the other 1 and 2 slot boards (including any different versions)

The MV1FZ I have has 3 layers.

mv-2fs = 3
mv-2f = 2
mv-4ft = 3

what would happen, if i'd drill a hole through an area, where i can't see any traces on both sides? is the layer in the middle only one large area, that is connected to gnd or are there real traces between the outer layers?

?

supergoose79:
mv-2fs = 3
mv-2f = 2
mv-4ft = 3

what would happen, if i'd drill a hole through an area, where i can't see any traces on both sides? is the layer in the middle only one large area, that is connected to gnd or are there real traces between the outer layers?

Click to expand...

there is a chance you could destroy an existing circuit on the middle board, so I'd avoid that at all costs.

time to find someone, who is willing & able to x-ray the upper board of my 4ft.

supergoose79:
mv-2fs = 3
mv-2f = 2
mv-4ft = 3

what would happen, if i'd drill a hole through an area, where i can't see any traces on both sides? is the layer in the middle only one large area, that is connected to gnd or are there real traces between the outer layers?

Click to expand...

There are real traces, especially around the Z80.(and other important areas for that matter)
It will be a good thing to compile this info.

almost forgot :

mv-2 = 2
mv-1b = hmmm ... the edge looks like the one of a 2 layer pcb, but i can't believe, that it has only 2 layers.

update

MV1 3
MV1B 2
MV1F 2
MV1FZ 3
MV2 2
MV2F 2
MV2FS 3
MV4 older ver 2
MV4 newer ver 3
MV4FT 3
MV6 2

<small>[ August 01, 2003, 11:04 AM: Message edited by: ttooddddyy ]</small>

Thanks for your help on this guys.
It may save a lot of continuity tracing issues.

<small>[ August 01, 2003, 10:59 AM: Message edited by: ttooddddyy ]</small>

i just had a closer look at the pics of broken's mv-1c. it's one of the 2layer boards.

btw : there are two different versions of the mv-1b. don't know, if there are any differences besides the layout/placement of the chips.