Transformator cables FZ-1

Jones · Post by **Jones** » Tue Mar 22, 2011 11:25 pm

Hi guys,

in my NTSC 3DO FZ-1 there are 3 cables connecting the transformator
with the PCB - 2 of them are supplying stepped down AC with approx.
15 Volts.

What is the single 3rd one for?

In my PAL machine, this 3rd cable is totally missing!

Regards,
Jones

Jones · Post by **Jones** » Tue Mar 22, 2011 11:35 pm

I've found this video on youtube in which someone switches the
PCB of a PAL machine with a NTSC PCB, using the same (PAL) transformator.

He also mentions that on the NTSC PCB there is a third plug somehow for transformators. But the board seems to work fine as well without
any connection!

http://www.youtube.com/watch?v=ia-vwB3KAX0

Any ideas what this 3rd cable is for?

awbacon · Post by **awbacon** » Thu Mar 24, 2011 3:21 am

This is just a guess, but may be correct

I assume the two cables are neutral and live, and the 3rd one on the NTSC may be ground.

Although the 3do plug for the wall does not have the ground post, so I could be off.

But thats my guess, one wire is your live, one is your neutral, and the 3rd is ground. Perhaps in N. America the ground is required, where in Europe it isn't?

Jones · Post by **Jones** » Thu Mar 24, 2011 9:02 am

This was also my first thought!

But why do NTSC PCBs have an additional groundline to the transformator though the American external power plugs dont, and why dont have the
PAL PCBs that groundline though the European external power plugs do?