How to build a creatiVision power supply

[mark-emark]

The damage, doesn't look so bad.

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[Scouter3d]

Hi,

I opened up my Creativision MKII (i guess yours is an MKII) an i found, that the internal PSU part is different to an MKI (and so different to the schematic one finds online...)

Using a 3 Wire Transformer (with centertapping) will NOT WORK with a Creativision MKII (not sure about the MKI, as i do not own one anymore...)
as it uses one Wire of the 18V AC as common Ground!!!!!

I made a very crude drawing of the insides of the CVMKII...

Any Electronic Gurus are welcome to comment, as i have no clue, why they built it that way... and if i am right in my opinion/conclusion?????

Greetings, TOM:0)

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[Mamejay]

I know this is an old thread but wanted to ask about the multi tapped power supplies
I do not understand how this could have done so much damage to mark-emark computer.
They should be separate voltages.

[Scouter3d]

Hi Mamejay,

i am not sure, but the way the centertapped supply was wired to the MKII console the internal PSU design might have allowed all the current to flow thru one of the diodes...

Or "reconnect" the 18V AC to the transformer at the point where only 9V should be?

It might also be really important "where exactly" the wires from the transformer where connected too the plug = if the "polarity" would have been spwapped (as the MKII uses the "lower" brown wire as "Ground" and not the "upper" two wires" as it was shown in the diagram on the previous page) it might have worked?????

Many "IFs" and "MAYBEs" , but here in Austria it is too early in the morning to think straight :0)

Cheers, TOM:0)